HomeMy WebLinkAbout2019-01-08 - AGENDA REPORTS - MOU WITH LACO DEPT OF PUBLIC HEALTH FOR ONSITE WAS (2)Agenda Item: 4
DATE: January 8, 2019
SUBJECT: MEMORANDUM OF UNDERSTANDING WITH LOS ANGELES
COUNTY DEPARTMENT OF PUBLIC HEALTH FOR ONSITE
WASTEWATER TREATMENT SYSTEM DESIGN REVIEW AND
OWNER PERMITTING
DEPARTMENT: Neighborhood Services
PRESENTER: Darin Seegmiller
RECOMMENDED ACTION
City Council approve the Memorandum of Understanding between the City of Santa Clarita
(City) and the Los Angeles County Department of Public Health regarding Onsite Wastewater
Treatment Systems and grant the City Manager signing authority.
BACKGROUND
On June 19, 2012, the State Water Resources Control Board adopted the Water Quality Control
Plan for Siting, Design, Operation, and Maintenance of Onsite Wastewater Treatment Systems
(OWTS Policy). This policy requires new or replacement Onsite Wastewater Treatment Systems
(OWTS), also known as septic systems, within the State to comply with a set of design standards
intended to prevent harmful bacteria from contaminating surface water or groundwater. The Los
Angeles Regional Water Quality Control Board (Regional Board) is responsible for enforcing
this policy locally. The Los Angeles County Department of Public Health (DPH) currently
reviews and permits OWTS within City of Santa Clarita (City) limits.
In July 2017, the City received a compliance letter from the Regional Board requiring data and
information with the intent of designating the City the responsibility of implementing the OWTS
Policy. However, by approving this MOU, the City would designate DPH for ensuring the
proper siting, design, operation, and maintenance of OWTS within the City.
The OWTS Policy allows local agencies, such as DPH, to assume responsibility for managing
OWTS by developing a Local Agency Management Program (LAMP). The DPH has recently
completed an approved LAMP, which allows the DPH to review and approve plans for siting and
designing new or modified OWTS consistent with the Statewide OWTS Policy. The LAMP also
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outlines plans to ensure proper ongoing operation and maintenance of OWTS within the City.
The LAMP is codified in the Los Angeles County Public Health Code (which the City of Santa
Clarita has adopted by reference, per Santa Clarita Municipal Code Section 9.02.010). This
arrangement requires property owners who use an OWTS to work with the DPH instead of the
Regional Board for the permitting of OWTS systems.
The benefits for residents in the City of DPH assuming the responsibility of managing the
OWTS Policy are primarily convenience and cost. Without action, residents would have to work
with the Regional Board, with offices located in Downtown Los Angeles, and would assume
higher costs for permitting and review.
Under the terms of the new OWTS Policy, in order for the DPH to provide plan review services
and implement the additional items listed below within the City's boundaries, the City must enter
into a Memorandum of Understanding (MOU) with the DPH to participate in the DPH's LAMP.
Entering into this MOU will allow DPH to review OWTS plans for siting and design as well as
ensuring proper operation and maintenance of OWTS. Without this MOU, the City would need
to develop its own LAMP to be consistent with the OWTS Policy and have it approved by the
Regional Board. The City would be required to review and permit OWTS plans in addition to
developing a comprehensive program to ensure proper operation and maintenance of existing
OWTS. If the City does not develop its own LAMP or enter into an MOU with DPH, then the
City must refer OWTS property owners to the Regional Board for a Waste Discharge Permit.
Services will be funded through the collection of a one-time plan review fee by DPH, currently
$1,528 for a standard OWTS system, and $1,985 for a non -conventional OWTS system.
Additionally, all current OWTS property owners will be charged an annual fee of $5.00 per year
as a separate line item on their respective property tax bills. This will only affect a small
percentage of residents within the City of Santa Clarita that are not connected to the sewer
system and have an OWTS for their wastewater needs.
In summary, the MOU requires the DPH to do the following:
• Review new, replacement, or repair of OWTS for siting, design, and setback
requirements.
• Provide approval of the OWTS application, a detailed list of corrections needed to
proceed with the application, or a detailed reason why the project is unable to be
approved.
• Require an evaluation by a qualified professional of all OWTS that are determined to be
exhibiting signs of failing. The County will issue compliance orders when it is
determined the system needs to be replaced or repaired.
• Issue an operating permit to all existing and new OWTS.
• Maintain a database of all non -conventional OWTS, including when the system was
serviced, and the results of any effluent testing.
• License all sewage pumper trucks within the City's jurisdiction.
The MOU requires the City to do the following:
• Refer building permit applications with a new or existing OWTS to DPH for review.
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• Refer property that does not meet OWTS siting or design requirements to the Los
Angeles Regional Water Quality Control Board for a Waste Discharge Requirements
(WDR) permit.
• Refer any complaint alleging an OWTS is failing to DPH for investigation.
• Investigate whether an OWTS was constructed or modified without a permit.
• Provide enforcement for any system that fails to comply with the OWTS ordinance, as
incorporated by reference into the Santa Clarita Municipal Code, section 9.02.010.
ALTERNATIVE ACTION
Other action as determined by Council.
FISCAL IMPACT
There is no direct fiscal impact to the City.
ATTACHMENTS
MOU for DPH OWTS Review
LAMP Ordinance (available in the City Clerk's Reading File)
State OWTS Policy (available in the City Clerk's Reading File)
DPH LAMP (available in the City Clerk's Reading File)
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MEMORANDUM OF UNDERSTANDING
BETWEEN
THE COUNTY OF LOS ANGELES, DEPARTMENT OF PUBLIC HEALTH
AND
THE CITY OF SANTA CLARITA
REGARDING ONSITE WASTEWATER TREATMENT SYSTEMS
EFFECTIVE DATE:
RECITALS
WHEREAS, the State of California adopted Assembly Bill 885 in September 2000, to require the State
Water Resources Control Board to adopt specific regulations or standards for the permitting and
operation of onsite wastewater treatment systems (OWTS).
WHEREAS, the State Water Resources Control Board adopted the Water Quality Control Plan for
Siting, Design, Operation, and Maintenance of Onsite Wastewater Treatment Systems (OWTS Policy)
on June 19, 2012 and it became effective on May 13, 2013.
WHEREAS, the OWTS Policy establishes a waiver of Waste Discharge Requirement permits for OWTS
systems meeting the criteria of the OWTS Policy.
WHEREAS, the OWTS Policy establishes low risk siting and design requirements for OWTS subject to
the OWTS Policy and authorizes local agencies to submit a Local Agency Management Program
(LAMP) to the Regional Water Quality Control Board for approval of alternate methods of siting and
design to achieve the same purpose.
WHEREAS, the County of Los Angeles, Department of Public Health (DPH) operates a program for
the approval of the siting, design, operation and maintenance of OWTS for individual residences
within its Environmental Health Division and has adequate staffing and technical knowledge to meet
the requirements of the OWTS Policy.
WHEREAS, the County of Los Angeles (County) has submitted a LAMP to the Los Angeles Regional
Water Quality Control Board for approval.
WHEREAS, the California Regional Water Quality Control Boards, upon mutual agreement, may
designate one Regional Water Quality Control Board to regulate a person or entity that is under the
jurisdiction of two or more Regional Water Quality Control Boards (Water Code Section 13228).
WHEREAS, the OWTS Policy Section 4.3 states that the Regional Water Quality Control Board
designated in Attachment 3 shall review, and if appropriate, approve a Local Agency Management
Program submitted by the local agency pursuant to Tier 2 in this Policy.
WHEREAS, OWTS Policy Attachment 3 identifies Los Angeles Quality Control Regional Board as the
designated Regional Water Quality Control Board for the County of Los Angeles for purposes of
reviewing and, if appropriate, approving new Local Agency Management Plans (LAMP).
WHEREAS, the Los Angeles Regional Water Quality Control Board has reviewed the County's LAMP,
determined that it meets the requirements of the OWTS Policy, approved the County's LAMP on
{Date} for those areas within both the Los Angeles and Lahontan Regional Water Quality Control
Boards, and as a result has granted a conditional waiver of waste discharge requirements for all
OWTS complying with the LAMP.
WHEREAS, the Los Angeles County Board of Supervisors approved Ordinance # 2018-0037 to
implement the requirements of the LAMP on October 2, 2018.
WHEREAS, the Los Angeles County Board of Supervisors delegated authority to the Director of Public
Health to enter into agreements with local jurisdictions to provide services under the LAMP.
WHEREAS, the City of Santa Clarita (City) has existing OWTS and areas without access to a public
sewer system.
WHEREAS, both the County of Los Angeles and the City are desirous of protecting the public's health
and the quality of groundwater within the City.
NOW THEREFORE THE COUNTY OF LOS ANGELES AND THE CITY OF SANTA CLARITA HEREBY AGREE
AS FOLLOWS:
DESIGNATION AND AGREEMENT
1. The City designates the County as the Qualified Local Agency (QLA) and the County accepts
the designation for the implementation of the County's approved LAMP for the siting,
design, operation, and maintenance of certain OWTS within the City's incorporated area.
2. The County and City agree that the County Health and Safety Code, Title 11, Chapter 38 and
Requirements and Procedures adopted by the Director of DPH and/or Health Officer of the
County and the County Plumbing Code will govern the applicable siting, design, operation,
and maintenance of OWTS within the City. City will adopt County's ordinance governing
OWTS into City's municipal code by resolution or ordinance.
3. The MOU shall be effective upon the date that City adopts County Ordinance # 2018-0037
into its municipal code and shall be in effect until terminated by either party in accordance
with Section V.
III. APPLICABILITY
OWTS subject to this agreement shall consist of those OWTS within the jurisdiction of the
City that generate 10,000 gallons per day or less of domestic wastewater (as that term is
defined in the OWTS Policy), that dispose of wastewater below the ground surface, that is
generated from single family residences, multi -family residences, commercial buildings
where the wastewater is from domestic sources (i.e., toilets, urinals, bathtubs, showers,
dishwashing facilities, laundry washing, and garbage disposals), buildings which are a
combination of commercial and residential, and commercial food service buildings with a
wastewater with a Biological Oxygen Demand (BOD) of 900 mg/L or less and a properly
functioning grease interceptor.
2. This MOU shall not apply to any other OWTS within the incorporated area of the City,
including those that:
a) Generate more than 10,000 gallons per day,
b) Discharge high strength wastewater, other than commercial food service
buildings meeting the above requirements,
c) Are commercial food service buildings that don't meet the above requirements,
d) Generate industrial wastewater,
e) Accept wastewater from Recreational Vehicles,
f) Utilize methods to dispose of wastewater above ground,
g) Treat and reuse wastewater onsite for non -potable uses.
3. Nothing in this MOU shall diminish or affect the ability of the City to exercise its authority
through the Plumbing Code to regulate the type, siting, design and installation, for those
OWTS that are exempt from the MOU to be operated within the incorporated area of the
City. Issuance of a Waste Discharge Requirement or other permit by a Regional Water
Quality Control Board shall not constitute authorization for any person or entity to
construct, install, or operate any OWTS without City approval.
IV. GENERAL PROVISIONS
COUNTY RESPONSIBILITIES
1. The County will notify the appropriate Regional Water Quality Control Board that the
City has entered an agreement to be regulated under the County's LAMP.
The County will review all applications for new, replacement or repair of OWTS for siting
and design.
3. The County will review all applications for building permits where an OWTS is present
on the property to evaluate whether the proposed construction will impact the OWTS
by:
• Potentially increasing wastewater flows,
• Changing the strength of the wastewater,
• Impinging upon required setbacks of the OWTS, any of its components, or the
required 100% future expansion area.
4. The County shall provide the owner of the property or his/her representative with an
approval of the application, a detailed list of corrections needed to proceed with the
application, or a detailed reason why the project is unable to be approved. Projects that
the County determines may impact ground or surface water may be directed to file a
Report of Waste Discharge with the Regional Water Quality Control.
5. The County will maintain an inventory of all OWTS permitted within the City's
incorporated area including OWTS Policy Tier, depth to groundwater, setback
information, and if a non -conventional onsite wastewater treatment system (NOWTS)
was required.
6. The County will require an evaluation by a qualified professional of all OWTS and
NOWTS which are determined to be exhibiting signs of failing. The County will issue
compliance orders to owners of OWTS or NOWTS when a qualified professional
determines the OWTS or NOWTS is in need of replacement or repair.
7. The County will issue an operating permit to all existing and new OWTS and NOWTS.
The County will maintain a database of all NOWTS, including when the system was
serviced by a service technician and the results of any effluent testing performed by a
California certified laboratory, as required by the LAMP.
8. The County will license all Sewage Pumper Trucks that service OWTS within the City's
jurisdiction.
9. The County will complete and submit an annual report by February 1 of each year
detailing the number, location, and description of permits issued for OWTS where a
variance is granted and assess the impact of OWTS discharges based on analysis of
water quality data, complaints, inspection results, monitoring data, and failures. Other
data outlined in the OWTS Policy, Section 9.32 will be reviewed if available.
10. The County will refer to the City for legal enforcement, any violation of the City's
ordinance where the property owner has failed to comply with the written directives of
the Health Officer or his/her duly authorized deputy.
11. The County may direct any property owner whose permit for a NOWTS is suspended or
revoked for failure to comply with the directives of the Health Officer to file a Report of
Waste Discharge with the Regional Water Quality Control Board. The County shall also
inform the Regional Water Quality Control Board that the property owner is no longer
operating under a waiver of Waste Discharge Requirements and is required to file a
Report of Waste Discharge.
CITY RESPONSIBILITIES
1. The City will provide the County with a list of all known domestic OWTS, all OWTS with
septic tanks greater than 10,000 gallons, OWTS with probable high strength waste
streams, and cesspools within the City's jurisdiction within 60 days of the effective date
of this agreement.
2. The City will annually provide the County with a list of properties where an existing
OWTS was decommissioned and the property connected to the public sewer.
3. The City shall notify the County whenever a new building with a NOWTS is issued a
Certificate of Occupancy.
4. The City shall refer any building permit application for a new building, remodel of an
existing building, repair of an existing OWTS, or construction of any building or
permanent structure which may impinge upon an OWTS or future expansion area to the
County. The City shall not issue a building permit for a project referred to the County
unless plans are first approved by the County.
5. The City shall require a property owner to submit a Report of Waste Discharge (RWD)
for issuance of Waste Discharge Requirements (WDR) by the appropriate Regional
Water Quality Control Board for any OWTS project that does not meet the requirements
identified in Section III of this agreement.
6. The City shall refer to the County any complaint alleging an OWTS is failing. The City
shall indicate whether the City desires to conduct a joint investigation of the complaint.
7. The City shall investigate any complaint alleging construction of an OWTS or
modification of an existing OWTS without obtaining the appropriate permits.
8. The City shall provide legal enforcement for any property owner who fails to comply
with the City's ordinance and written directives issued by the Health Officer or his/her
authorized deputy.
9. The City, upon cancellation of this MOU, shall comply with the Tier 1 requirements in
the State OWTS Policy until the Regional Water Quality Control Board has approved a
LAMP authorizing the City to use alternative requirements. If as a result of termination
of this contract the Regional Water Quality Control Board determines that a WDR is
required for existing NOWTS, the City shall be responsible for issuing a notice to the
owner of each property where a NOWTS is installed within their jurisdiction directing
the owner to obtain a WDR.
10. The City shall provide the County by December 31s' of each year with surface or
groundwater quality monitoring data for nitrates and pathogens that may be useful in
the County's annual Water Quality Assessment Program. The data may be collected by
the City as part of its National Pollutant Discharge Elimination System (NPDES) Permit
requirements, a City operated water utility, or other monitoring program.
V. TERM AND TERMINATION
1. The City may terminate this MOU, with or without cause, upon ninety (90) days written
notice. The City shall send all notices related to this MOU to:
County of Los Angeles Department of Public Health - Environmental Health Division
Director of Environmental Protection Branch
5050 Commerce Drive
Baldwin Park, CA 91706
The County shall send all notices related to this MOU to:
City of Santa Clarita
23920 Valencia Blvd.
Santa Clarita, CA 91355
2. The County may terminate this MOU, with or without cause, upon ninety (90) days
written notice from the Director of Public Health to the City.
3. Upon the effective date of the termination, the City shall become responsible for
enforcement of the State OWTS Policy within its jurisdiction.
4. In addition to the above, in the event that the State Water Board adopts new
regulations regarding OWTS, the County may, at its discretion terminate this MOU upon
the effective date of the new regulations. The City and the County, at their mutual
agreement, may negotiate and adopt an amendment to this MOU to include the new
regulations.
AUTHORIZING SIGNATURES
IN WITNESS WHEREOF, the parties hereto have executed this contract on this date of
FOR LOS ANGELES COUNTY, DEPARTMENT OF PUBLIC HEALTH:
By:
Print Name & Title
Date:
FOR CITY OF SANTA CLARITA:
KENNETH W. STRIPLIN, CITY MANAGER
By:
City Manager
Date:
APPROVED AS TO FORM:
JOSEPH M. MONTES, CITY ATTORNEY
By:
City Attorney
Date:
ANALYSIS
This ordinance amends Title 8 — Consumer Protection, Business and
Wage Regulations, and Title 11 — Health and Safety, to add a public health permit and
regulatory framework to enforce health and safety requirements for onsite wastewater
treatment systems (OWTS).
The State Water Resources Control Board (SWRCB) has regulatory
authority over OWTS. OWTS are septic systems installed on separate parcels of
property that are unable to connect to a municipal sewer system. OWTS capture and
treat domestic wastewater to reduce its polluting effect on the environment and protect
public health. SWRCB has promulgated an OWTS Policy that provides minimum
design and siting standards for low risk, new and replacement OWTS. SWRCB allows
local agencies to create their own alternative regulatory requirements that meet all
OWTS Policy requirements.
In response, the Environmental Health Division of the Department of
Public Health (DPN) created its Local Agency Management Program (LAMP) for
OWTS. LAMP provides alternate health and safety requirements for OWTS that have
been approved by both the Los Angeles Water Board and SWRCB. The LAMP
requirements, which will be incorporated into the Los Angeles County Code, will allow
DPH to regulate OWTS both within the unincorporated County and within cities that
enter into agreements with DPH for OWTS regulation by using a more flexible
enforcement scheme that is equally protective of public health as the OWTS Policy.
This ordinance has two regulatory components. It amends Title 8,
Chapter 8.04 to include new LAMP permit fees for Conventional OWTS, Non -
conventional OWTS, and Sewage/Septage Pumping Vehicle Operators. Further, this
ordinance amends Title 11, Division 1, Chapter 11.38, Parts 1 and 3. The ordinance
adds definitions to Part 1 of Chapter 11.38 that are needed for DPH's LAMP regulatory
requirements. The ordinance also renames Part 3 to Privies, Chemical Toilets, and
Cesspools. In Part 3, the ordinance deletes provisions that are out of date, and creates
HOA.102294191.1
new requirements for the use and maintenance of privies, chemical toilets, and
cesspools.
This ordinance also adds new Parts 5 and 6 to Title 11, Division 1,
Chapter 11.38. The new Part 5 adds the new LAMP requirements for DPH's regulation
of OWTS, both conventional and non -conventional. These new provisions include plan
review, siting, permitting, and operational requirements of OWTS. The new Part 6 adds
permitting requirements for Sewage Pumping Vehicles.
This ordinance will be effective in the unincorporated areas, and within the
jurisdictions of cities that enter into agreements with the County for the provision of
these OWTS inspection services. This action will permit DPH to enforce public health
permit requirements for OWTS within those jurisdictions. The County's costs for
conducting these regulatory services will be offset by permit fees paid by owners of
OWTS.
MARY C. WICKHAM
County Counsel
By
f•
ROBERT E. RAGLAND
Principal Deputy County Counsel
Health Services Division
LUM
Requested: 7/19118
Revised: 8130118
HOA.102294191.1
ORDINANCE NO.
An ordinance amending Title 8 -- Consumer Protection, Business and Wage
Regulations, and Title 11 — Health and Safety of the Los Angeles County Code, relating
to public health monitoring and enforcement of onsite wastewater treatment systems.
The Board of Supervisors of the County of Los Angeles ordains as follows:
SECTION 1. Section 8.04.420 is hereby amended to read as follows:
8.04.420 SeptiG tank, Gesspeel, GhemiGal toilet or- sewage
seepage- pit Gleaning meh!Gte-.Seepac�el5ewage Pumpinc�_Vehicle.
11
tank,SeptiG
Gesspeel, ohemiGal toilet eF sewage seepage Pit Gleaning
vehlsle"See a elsewa a pumping vehicle" means any vehicle used in whole or in part
for the transportation of septic tank, cesspool, chemical toilet, or sewage seepage -pit
cleanings.
SECTION 2. Section 8.04.720 is hereby amended to read as follows:
8.04.720 Fee Schedule.
sBusiness Classification
I
Permit Fee
Animal food market
3
3
$175.00
Onsite Wastewater Treatment Systems:
I
Conventional
$5.00
Non -Conventional
I
43.00
HOA.102294191.1
Seepage/sewage pumping vehicle operator
124.00
Personal hawker: 1$224.00
SECTION 3. Section 11.38.015 is hereby added to read as follows:
1.1.38.015 Average Annual Rainfall.
"Average annual rainfall" means the average annual amount of precipitation for a
location over a year as measured by the nearest National Weather Service station for
the preceding three decades. For example, the data set used to make a determination
in 2016 would be between 1981 — 2010.
SECTION 4. Section 11.38.018 is hereby added to read as follows:
11.38.018 Cesspool.
"Cesspool" means an excavation with permeable sides and/or bottom that
receives untreated sewage, wastewater, or drainage and is designed to retain organic
matter or solids but permits liquids to seep through the bottom or sides.
SECTION 5. Section 11.38.025 is hereby added to read as follows:
11.38.025 Covenant.
"Covenant" means a written agreement between the property owner and the
Director that runs with the land for the benefit of the County, which is recorded and filed
with the Los Angeles County Registrar-Recorder/County Clerk.
HOA.102294191.1 2
SECTION 6. Section 11.38.033 is hereby added to read as follows:
11.38.033 Domestic Wastewater.
"Domestic wastewater" means wastewater normally discharged from plumbing
fixtures, appliances, and other household devices including toilets, sinks, showers,
bathtubs, kitchen sinks, laundry washing machines, dishwashing machines, and
garbage disposals. Domestic wastewater includes wastewater normally discharged
from commercial buildings such as office buildings, retail stores, and restaurants with a
properly sized and functioning grease interceptor where, the wastewater does not
exceed nine hundred (900) mg/L Biochemical Oxygen Demand (BOD) or from industrial
facilities where domestic wastewater is segregated from industrial wastewater.
Domestic wastewater does not include onsite wastewater treatment systems receiving a
majority of its wastewater from recreational vehicle (RV) holding tank discharges, such
as at RV dump stations.
SECTION 7. Section 11.38.035 is hereby added to read as follows:
11.38.035 Effluent.
"Effluent" means sewage or partially treated sewage flowing out of a septic tank,
aerobic treatment unit, dispersal system, or other onsite wastewater treatment system
component.
SECTION 8. Section 11.38.042 is hereby added to read as follows:
11.38.042 Falling Onsite Wastewater Treatment System.
"Failing onsite wastewater treatment system" means a conventional or non -
conventional onsite wastewater treatment system that is no longer able to safely treat or
HOA.102294191.1 3
discharge wastewater, which may present a health risk to humans or adversely impact
the environment. Factors that evidence a failing onsite wastewater treatment system
include, but are not limited to:
A. A backup of sewage into a structure which is caused by a septic tank or
dispersal system malfunction other than a plumbing line blockage.
B. A discharge of sewage or effluent to the ground surface.
C. A septic tank that requires pumping more than two (2) times within a one
hundred eighty (180) day period in order to provide adequate dispersal of sewage.
D. A structural failure that causes effluent to discharge at a location other
than where intended or allows groundwater to infiltrate the system.
E. A system affects or will likely affect groundwater or surface water to a
degree that makes the water unfit for drinking or other domestic uses or causes a
human health hazard or other public nuisance condition.
F. Inability to use the onsite wastewater treatment system as intended.
SECTION 9. Section 11.38.044 is hereby added to read as follows:
11.38.044 Feasibility Report.
"Feasibility report" means the documents, test results, and geological reports
required to be prepared and submitted to the Director in order to demonstrate the
feasibility of installing an onsite wastewater treatment system or a non -conventional
onsite wastewater treatment system, including the entirety of any future expansion area.
HOA.1 02294191.1 4
SECTION 10. Section 11.38.046 is hereby added to read as follows:
11.38.046 Future Expansion Area.
"Future expansion area" means an area designated and tested as the location for
an additional dispersal system capable of handling one hundred (100) percent of the
wastewater from the onsite wastewater treatment system once the original dispersal
system fails.
SECTION 11. . Section 11.38.048 is hereby added to read as follows:
11.38.048 Groundwater.
"Groundwater' means water located below the land surface in the saturated zone
of the soil or rock. Groundwater includes perched water tables, shallow water tables,
and zones that are seasonally or permanently saturated.
SECTION 12. Section 11.38.052 is hereby added to read as follows:
11.38.052 Impaired Water Body.
"Impaired water body" means those surface water bodies or segments thereof
that are identified on a list approved first by the State Water Resources Control Board
and then approved by the U.S. Environmental Protection Agency (EPA) pursuant to
Section 303(d) of the Federal Clean Water Act.
SECTION 13. Section 11.38.055 is hereby added to read as follows:
11.38.055 Non -Conventional Onsite Wastewater Treatment_ System
NOL WTS).
"Non -conventional onsite wastewater treatment system" or (NOWTS) means an
onsite wastewater treatment system that utilizes, in addition to the septic tank, one (1)
HQA,102294191.1 5
or more supplemental treatment components and may include an alternative dispersal
system. Supplemental treatment may include systems to reduce the nitrogen
concentration of the effluent, provide disinfection of the effluent, or both.
SECTION 14. Section 11.38.075 is hereby added to read as follows:
11.38.075 Onsite Wastewater Treatment System (OWTS).
"Onsite wastewater treatment system" or (OWTS) means a sewage disposal
system consisting of a wastewater holding tank and a method to dispose of treated
effluent below the ground surface. The term OWTS refers to both conventional and
non -conventional onsite wastewater treatment systems.
SECTION 15. Section 11.38.078 is hereby added to read as follows:
11.38.078 OWTS Requirements and Procedures.
"OWTS requirements and procedures" means the required standards and
procedures promulgated by the Director for the installation, operation, and discharge of
effluent by conventional and non -conventional OWTS.
SECTION 16. Section 11.38.080 is hereby amended to read as follows:
11.38.080 Privy sStructure.
"Privy structure" means a room or compartment constructed over an eaFth pft,a
water tight vault or tank, into which human fecal matter or urine is to be deposited.
SECTION 17. Section 11.38.092 is hereby added to read as follows:
11.38.092 Seepage Pit.
"Seepage pit" means an excavation at least ten (10) feet deep and three (3) to
six (6) feet in diameter, typically cylindrical in shape with six (6) inches of rock between
HOA.102294191.1 6
the pit wall and a concrete or brick liner, constructed for the purpose of disposing of
sewage effluent from a septic tank or treatment tank.
SECTION 18. Section 11.38.094 is hereby added to read as follows:
11.38.094 Septic Tank.
"Septic tank" means a water tight, compartmentalized, covered receptacle
designed for primary treatment of wastewater and constructed to:
A. Receive wastewater discharged from a building.
B. Separate settleable solids from liquid.
C. Digest organic matter by anaerobic bacterial action.
D. Store digested solids.
E. Clarify wastewater for further treatment with final subsurface discharge.
SECTION 19. Section 11.38.096 is hereby added to read as follows:
11.38.096 Sewage.
"Sewage" means waste substance, liquid or solid, which contains or may contain
human or animal excreta or excrement.
SECTION 20. Section 11.38.098 is hereby added to read as follows:
11.38.098 Telemetric Monitoring.
"Telemetric monitoring" means the ability to automatically measure and transmit
OWTS data by wire, radio, or other means.
HOA.102294191.1 7
SECTION 21. Division 1, Part 3 of Chapter 11.38 of the Los Angeles
County Code amended to read as follows:
Park 3 Sanitation, Sewage Despesal and industrial
WastePrivies, Chemical Toilets, and Cesspools.
SECTION 22. Section 11.38.450 is hereby deleted in its entirety:
A
M. - MAMA �' J!�'IIl-i�l�'I l- ►= YIYYI�C�JIl1:Jl YIl�l-1_IILJ�Il1l JiL�I:ll�]!�!'�iSJsllrP�lllL�Ji-i!L_rlf_1�-�
SECTION 23. Section 11.38.460 is hereby deleted in its entirety:
�:
mains,A. Water mains shall be at a leroatien as faF as possible abeve the elevation of
the hGFiZ-Gntal distanGe between
SUGh mains and SUGh sanitary sewers shall be at least 10 feet. in the Gase ef gFavit
wateF mains, the herizental dostaRGe between SUGh mains and SUGh sanitary seweFs
shall be at least 25 feet, Where a wateF main and a seWeFline must Gross, the wateF
rAa!R shall be at an elevatien abeve the sewer and shall be separated from such sewe
by at least three feet of undistuFbed OF GGmparted eaFth-.
__SA here the above requirements .+ Remit he met heEa se of topography a
B. IV \IIV above iV4.�V11 W11[VIFi.�3"'{JCJt-
other physieal Ganditions, the materials and joints of beth water mains and seweF lines
shall be installed in SUGh a manner and shall pessess the neGessary strength and
durability as to pFevent the escape ef
liquids and gases
7 1
known adverse GOnditions sueh as
1 stFains due to tempeFatUrze 1
settlement and supeFiMpOsed lea4s-.
SECTION 24. Section 11.38.470 is hereby deleted in its entirety:
systems=
When the iRstallatien of private sewage disposal systems is peFMitted by the
following table:
HOA.102294191.1
House �SeptiG Disposal Seepage PR--Gf
2 fee '5 fee 18 fee 8 feet l8UI'diAg6 OF StFUGtUFes
pNvate **
50 fee 59 dept 59 feet Fwo feet 1Water supply wells***
F
59 fee k 59 deet , 50 2E ' 00 fPEt beams**
[ i
110 fee 110 fee 10 feet
5 feet 112 feet
!Seepage Hilo or nennneoln*
15 fee 14 feet € 5 feet ? D+5p6
1 fee 5 feet 5 -feet i5 -feet paFneiE; w tee
26 feet 125 feet �25 feet 125 fee
"lam
five feel ef_tight line_
Where speGial hazards are involved, the d'StaPGe required may be inGFeaSed, as
may he diree+leed by the Djrenlnr of nuhlin health
HOA.102294191.1 10
SECTION 25. Section 11.38.490 is hereby amended to read as follows:
11.38.490 Privies—Location rRestrictions.
it is unlawful tG GGRGtFUG5t, maintain oF keep a pFivy within 35 feet from an
•
or privy structure shall only be installed in remote public or private recreation areas
where there is no running water or practical means of sewage disposal. Privies shall
only be permitted to be installed where they are accessible for servicing by a
seepage/sewage pumping vehicle. A privy or privy structure shall not be in close
proximity of any food establishments of any kind or character. A privy, or privy structure
shall not be associated with any residential dwelling. When determined by the Director
that necessity for permitted privy or privy structure no longer exists, the Director may
revoke the permit. No person shall continue to maintain a privy after the permit for
maintenance thereof has been revoked. Whenever any privyor primy structure is to be
abandoned or no longer in service notification shall be provided to the Director, and
destruction of the privy or privy structure shall be accomplished in a manner approved
by the Director.
SECTION 26. Section 11.38.500 is hereby amended to read as follows:
11.38.500 Privies—Construction eSpecifications.
It is unlawful to erect or maintain a privy unless a suitable shelter is provided to
afford privacy and protection from the elements. The openings of such structure shall
be enclosed by metal mosquito -screening. The door thereof shall be so constructed as
to close automatically by means of a spring or other device.
HQA.102294191.1 11
The construction of the privy structure shall be such as to exclude all rodents,
flies and other insects from the -Wank or vault. The privy structure shall be maintained
in good repair, in a clean and sanitary condition, and free from flies, other insects and
rodents, and shall be properly ventilated. The tank or vault where waste is held shall be
made of a water tight material and all seams or joints shall be water tight. The privy
structure over the dank or vault shall completely cover the eaFthpiftank or vault
and shall be mounted on a cement or masonry foundation at least four (4) inches wide
and extending at least six (6) inches above and twelve (12) inches below ground level.
The earthpittgnk or vault shall be at least four (4) feet deep and shall be provided with a
vent at least six (6) inches in cross -Sectional dimension, extending from the pit to a
point higher than the highest point of the roof. Such vent shall be effectively screened.
There shall be an access port to allow cleaning of the tank or vault by a sewage
cleaning and car[ying vehicle.
SECTION 27. Section 11.38.510 is hereby amended to read as follows:
11.38.510 Privies—Maintenance.
The eat-Wgnk or vault of a privy shall not be permitted to become filled with
excreta nearer than two (2) feet from the surface of the ground. The content of the privy
shall be pumped out as needed by a seepage/sewage pumping vehicle permitted by the
Director.
HOA.1 02294 1 91.1 12
SECTION 28. Section 11.38.520 is hereby amended to read as follows:
11.38.520 P..iviesPFahibTted w efe Ch m:ral toilet
r StFirotiens.Earthen Pit Privies and Cesspools — Construction Prohibited
situated eithep one OF MOFe 1 itineFant 1 food establishments,
slaughteFhouses, 7 milk depots, Fnilk plants, milk pFedurAs plants,
OF five e
itineFant
food
i ! establishments, slaughterhouses,
farms,dairy milk depots, rnilk plants, milk produGts plants,
or five or mere
l�l!li�l�l�Ji �l�Jl�11�1��1�]!ll1�J �'J•�I tYEI�>t�l�a�!!t1'J•�l��l�R �S�L�L�II JL+J��l�2Tf �J lel'.I�LRi.��ll+l'�'1R'.�IR\ILr.E�
l'll�l�l l�>•Ytl�l L�)E [�l�LiJl l�Itl�IIEI �'1'l�ll�la JeS�l�l l�>•[�l•!\J•+Ji�L�]\l�]�Ii�ll+i�l![;MWAMQR'L Ql�L�iwE[+lw i
1 wateF I 1 wells, 7 lake, 1
L J1[rl� ei il�lliJil1t� �'11.i�'aJ7a]il�liL<l�f tl 2I\
ISL+fa+7ti�r1�+1�E�IlYYYIlYi�YYiWIYI�\rl YllllryJ\frl SrY'YW YY L�]IYI` lY�1r]Lillltrllir.It�iR'��J\.11 rl�l/LrJl �l�lnl�llf�l ilrlfl
HOA,102294191.1 13
the original graun44evel.—The construction of new earthen pit privies and cesspools is
prohibited. An earthen pit pray or cesspool currently in existence may continue to be
used until it is determined that the earthen pit privy or cesspool has failed, is
structure served by a cesspool in a manner that could increase wastewater flow.
I V TRIffifflgi I 1 11111
i I Fill: �11 1UT • - • - • 0 1
It is unlawful for any person to construct, maintain or keep a privy in any location
source of water. In no case shall a privy be constructed, maintained, or kept less than
Wone hundred (100) feet from any stream, water channel, spring, or well, and two
- 11 1 � i 1 11 11'' � III I 1� III 111 111
I I 1I C I
j§Rcf:**a
Chemical toilets are intended to serve non-residential, limited use activities, such
as field labor operations, special events, and temporary construction sites where
connection to the sewer or construction of an OWTS is not practicable. Except for
those activities covered under California Occupational Health and Safety requirements
electric transmission lines, the use of chemical toilets at a location for over three (3)
days requires a public health permit.
HOA.102294191.1 14
SECTION 31. Part 5, Chapter 11.38 of the Los Angeles County Code is
hereby added to read as follows:
Part 5 Requirements for Onsite Wastewater Treatment
Systems.
11.38.700 Discharge of Material or Li uid.
A. No person shall allow sewage, domestic or industrial wastewater, or any
matter or substance, offensive, injurious, or dangerous to health, to empty, flow, seep,
or drain onto the surface of any land.
B. No person shall allow sewage, treated effluent, or any matter or
substance, offensive, injurious, or dangerous, to health to empty, flow, seep, or drain
into, or affect any well, spring, stream, river, lake or other waters.
C. A violation of this Section is declared a public nuisance.
11.38.710 OWTS Requirements and Procedures.
The Director shall promulgate the OWTS requirements and procedures within
thirty (30) calendar days of the adoption of this ordinance. The OWTS requirements
and procedures shall be made available to the public at no charge, upon request, The
Director shall review the requirements and procedures a minimum of once every five
(5) years and amend the OWTS requirements and procedures as necessary to protect
the health of the public and the waters of the State. The Director shall provide notice to
the public of any proposed change(s) and provide members of the public an opportunity
to comment prior to implementation.
HOA.102294191.1 15
11.38.720 Onsite Wastewater Treatment Systems — Plan Review
and Permit Requirements.
A. The Director shall have the authority to require the submission of any
plans and specifications pertaining to or impacting onsite wastewater treatment
systems. Such plans include, but are not limited to, subdivision of parcels where a
public sewer is not available, building expansion, and the addition of a structure on a
parcel of property utilizing an onsite wastewater treatment system.
B. A person proposing to construct, install, alter or repair any onsite
wastewater treatment system or part thereof, or a privy structure shall submit an
application and receive plan approval from the Director in accordance with the
requirements of this Chapter and Title 28, Plumbing Code, including Appendix H, of the
Los Angeles County Code and with the OWTS requirements and procedures prior to
any work being performed.
C. A person proposing to construct or expand a building or other structure,
upon which property an onsite wastewater treatment system or non -conventional onsite
wastewater treatment system is installed, shall submit an application and receive a plan
approval from the Director. The Director's evaluation of the proposed construction or
expansion plan shall determine whether the new building, structure or expansion
interferes with the existing onsite wastewater treatment system or any future expansion
area required by Los Angeles County Code, Title 28, Plumbing Code.
D. An application shall be made on forms provided for that purpose by the
Director. Any required fee shall be paid at the time of application.
HOA.102294191.1 16
E. The Director's approval of an onsite wastewater treatment system plan
under this Section is separate from, and does not constitute compliance with, any permit
requirements contained elsewhere in this code, including, but not limited to, the
requirements under this Title 11 for obtaining a renewable operating permit for NOWTS
and any requirements under Title 28, Plumbing Code for obtaining a permit for the
construction or installation of an OWTS.
F. All onsite wastewater treatment systems must be installed in accordance
with the plans as approved by the Director. Any changes in the installation plans must
be reviewed and approved by the Director prior to installation.
G. Any plan approval issued by the Director shall be valid for one (1) year
from the date of approval. If a property owner has not obtained a building permit within
one year, a property owner may request an extension of the plan approval for up to one
(1) additional year. If the property owner has not obtained a building permit within two
(2) years, the property owner must submit a new application meeting the requirements
of the most recent version of the California Plumbing Code, and pay the required fee.
11.38.730 Restrictions on Use of OWTS when a Public Sewer is
Available.
The Director shall not issue a permit for a new onsite wastewater treatment
system, approve the repair or replacement of an onsite wastewater treatment system,
nor approve a project requiring the evaluation of an existing onsite wastewater
treatment system if a public sewer is available within two hundred (200) feet of the
building or proposed building.
HaA.1 022941 91.1 17
11.38.740 Limitations on Sub -Divisions without Public Sewer
Available.
Land development projects including Conditional Use Permits (CUP) and parcel
subdivision projects where a public sewer is not available and that are proposed after
the effective date of this ordinance, shall require the installation,of a non -conventional
onsite wastewater treatment system if the parcel size is smaller than the allowable
density values in the following table for a single family dwelling unit, or its equivalent.
The requirement for a NOWTS requires recordation of a covenant through the County
Office of the Registrar-Recorder/County Clerk as part of the approval of the CUP or
approval of the new parcels.
Average Annual
Rainfall
(inches/year)
Allowable Density Value
(acres/ single family
dwelling unit)
0-15
2.5
>15 — 20
2
>20 — 25
1.5
>25 — 35
1
>35 — 40
.0.75
>40
0.5
HOA.102294191.1 18
11.38.750 Horizontal Setback Requirements.
OWTS shall not be installed in such a manner that any of its components are
located within the horizontal setbacks identified in the following table.
Minimum Horizontal Distance
Septic Tank
Disposal Field
Seepage Pit
in Clear Required From:
5 feet
8 feet
8 feet
Buildings or Structures'
1.52 meters)
(2.44 meters)
2.44 meters)
Property line adjoining private
5 feet
5 feet
8 feet
property
(1.52 meters)
1.52 meters)
(2.44 meters)
Public Water Well, Where
200 feet
200 feet
depth of effluent dispersal
(61 meters)e(61
meters)
system X10 feetT8
Public Water Well, Where
150 feet
150 feet
depth of effluent dispersal
(45.7 meters)
45.7 meters)
system s10 feet'
Springs, and Flowing Surface
100 feet
100 feet
150 feet
ater',
30.5 meters)
(30.5 meters)
45.7 meters)
Vernal Pools, Wetlands,
00 feet
00 feet
00 feet
Lakes, Ponds, or Other (Non-
(61 meters)
61 meters)
(61 meters)
Flowing) Surface Water
Bodies'.'°
HOA.1 02294191.1 19
HOA.102294191.1 20
5 feet
5 feet
12 feet
Seepage pits
(1.52 meters)
(1.52 meters)
(3.66 meters)
5 feet
4 feet
5 feet
Disposal field
(1.52 meters)
(1.22 meters)
(1.52 meters)
On site domestic water service
5 feet
5 feet
5 feet
line
1.52 meters)
(1.52 meters)
(1.52 meters)
5 feet
5 feet
Distribution box
(1 .52 meters)
1.52 meters)
10 feet
10 feet
10 feet
Pressure public water main
3.05 meters)
(3.05 meters)
(3.05 meters)
100 feet
100 feet
150 feet
Private Water Wells'
(30.5 meters)
30.5 meters)
(45.72 meters)
100 feet
100 feet
100 feet
Monitoring wells"
(30.5 meters)
(30.5 meters)
30.5 meters)
Unstable Land Mass or Areas
100 feet
100 feet
100 feet
Subject to Earth Slides 12
(30.5 meters)
(30.5 meters)
(30.5 meters)
High Water Mark of Reservoir,
00 feet
400 feet
400 feet
Lake, or Flowing Water Body,
(122 meters)
(122 meters)
(122 meters)
Type 113
HOA.102294191.1 20
h Water Mark of Reservoir, 00 feet
.e, or Flowing Water Body, 61 meters)
ie 1114
runk of any tree
0 feet
3.05 meters)
!00 feet
61 meters)
0 feet
3.05 meters)
?00 feet
61 meters)
0 feet
05 meters)
When disposal fields and/or seepage pits are installed in sloping ground, the
ninimum horizontal distance between any part of the leaching system and ground
surface shall be fifteen (15) feet (4.57 meters).
1. Including decks, patios, porches and steps, whether covered or
uncovered, breezeways, roofed porte-cocheres, roofed patios, carports, covered
walks, covered driveways, and similar structures or appurtenances.
2. Reserved.
3. Reserved.
4. Plus two (2) feet (.61 m) for each additional one (1) foot (.305 meters) of
depth in excess of one (1) foot (.305 meters) below the bottom of the drain line. (See
also Section K 6 in Appendix K of the Plumbing Code.)
5. Reserved.
6. These minimum clear horizontal distances shall also apply between
disposal field, seepage pits, and the ocean mean higher high tide line.
HOA.102294191.1 21
7. Where special hazards are involved, the distance required shall be
increased as may be directed by the authority having jurisdiction.
8. If the depth of the effluent dispersal system exceeds twenty (20) feet
(6.1 meters) and is within six hundred (600) feet (182.88 meters) of a public water well,)
the setback must be such that there is at least two-year travel time for microbiological
contaminants.
9. Includes springs and flowing surface water bodies where the edge of that
water body is the natural or levied bank for creeks and rivers, or may be less where
site conditions prevent migration of wastewater to the water body.
10. Distance from vernal pools, wetlands, lakes, ponds, or other surface
water bodies where the edge of that water body is the high water mark for lakes and
reservoirs, and the mean high tide line for tidally influenced water bodies.
11. Where regulatory or legitimate data requirements necessitate, the
required distance to monitoring wells may be decreased as may be directed by the
authority having jurisdiction. If the monitoring well is installed to monitor the
groundwater at the waste effluent discharge, the setbacks do not apply.
12. Unstable land mass or areas subject to earth slides shall be identified by
a registered engineer or registered geologist; other setback distances are allowed, if
recommended by a geotechnical report prepared by a qualified professional.
13. Four hundred (400) feet (121.92 meters) from the high water mark of a
reservoir, lake, or flowing water body when the effluent dispersal system is within one
thousand two hundred (1,200) feet (365.76 meters) from a public water systems'
HOA.102294191.1 22
surface water intake point, within the catchment of the drainage, and located such that
it may impact water quality at the intake point such as upstream of the intake point for
flowing water bodies.
14. Two hundred (200) feet (60.96 meters) from the high water mark of a
reservoir, lake, or flowing water body when the effluent dispersal system is located
more than one thousand two hundred (1,200) feet (365.76 meters) but less than two
thousand five hundred (2,500) feet (762 meters) from a public water systems' surface
water intake point, within the catchment of the drainage, and located such that it may
impact water quality at the intake point such as upstream of the intake point for flowing
water bodies.
15. For oak trees, this requirement extends to five (5) feet (1.52m) outside of
the drip line or fifteen (15) feet (4.57 meters) from the trunk, whichever is greater.
In the event of inconsistencies between the setback requirements specified in the
Los Angeles County Plumbing Code, Title 28, Appendix H, the California Well
Standards, and Chapter 38, Part 2 of this code, the more restrictive requirements shall
prevail.
11.38.760 Requirements for Soil Depth and Vertical Distance to
Groundwater.
A. A conventional OWTS shall have a minimum five (5) feet of natural
undisturbed soil, excluding bedrock, below the bottom of a leach line, leach bed, or
infiltrative chamber.
HOA.102294191.1 23
B. A conventional OWTS shall have a minimum five (5) feet of separation
from the bottom of the leach line, leach bed, or infiltrative chamber and the highest
known groundwater level if the percolation rate is five (5) minutes per inch to sixty (60)
minutes per inch.
C. A conventional OWTS shall have a minimum of twenty (20) feet of vertical
separation from the bottom of the leach line, leach bed, or infiltrative chamber and the
highest known groundwater if the percolation rate is greater than one (1) minute per
inch but less than five (5) minutes per inch.
D. A NOWTS shall have a minimum of three (3) feet of natural undisturbed
soil, excluding bedrock, below the bottom of the leach line, leach bed, or infiltrative
chamber.
E. A NOWTS shall have a minimum of two (2) feet of separation from the
bottom of the leach line, leach bed, or infiltrative chamber and the highest known
groundwater level, except in areas near impaired water bodies where the minimum
distance shall be three (3) feet.
F. Any OWTS utilizing a seepage pit shall have a minimum separation of ten
(10) feet from the bottom of the pit to the highest known groundwater.
11.38.770 Structural Re uirements for Septic Tanks.
It shall be unlawful to install a septic tank in a manner that does not comply with
the following requirements:
A. All new or replacement tanks shall be approved by the International
Association of Plumbing and Mechanical Officers (IAPMO) or stamped and certified by
HOA.102294191.1 24
a California registered civil engineer as meeting industry standards and installation shall
be accomplished to the manufacturer's recommendations.
B. New and replacement tanks on conventional OWTS shall be equipped
with an effluent filter to prevent solids in excess of 3/1 6th of an inch from passing to the
dispersal area. Septic tanks that use a National Sanitation FoundationlAmerican
National Standards Institute (NSF/ANSI) Standard forty-six (46) effluent filter shall be
deemed in compliance with this requirement.
C. All joints between the septic tank and its components shall be watertight
and constructed of solid, durable materials to prevent excessive corrosion or decay.
D. The invert level of the inlet pipe shall be at least two inches higher than
the invert level of the outlet pipe.
E. All septic tank access points shall have watertight risers the tops of which
are set not more than six (6) inches below grade. Access openings at grade or above
shall be locked or secured to prevent unauthorized access.
11.38.780 OWTS Utilizing Pumps to Move Effluent.
OWTS that utilize pumps to move effluent to the septic tank or from the septic
tank to the dispersal system shall:
A. Be equipped with a visual, audible, or telemetric alarm that alerts the
owner or service provider in the event of pump failure.
B. Provide sufficient additional storage space in the second compartment of
the septic tank or pump chamber during a twenty-four (24) hour power outage or pump
failure and shall not allow an emergency overflow discharge. The capacity for the
HOA. OM4191.1 25
storage space shall be equal to 60 — 75 percent of the interior capacity of the pipes to
be dosed.
11.38.790 Percolation Rates for Dispersal Fields.
As an alternative to the percolation rates required in Appendix H of Los Angeles
County Code, Title 28 (Plumbing Code), proposed OWTS utilizing a leach bed, leach
field, or infiltrative chamber may report percolation test results as Minutes Per Inch
(MPI). Percolation rates in MPI shall be either:
A. In the range between five (5) MPI and sixty (60) MPI for use with a
conventional OWTS.
B. In the range between one (1) MPI and 4.9 MPI with a separation between
the bottom on the dispersal system and groundwater of at least twenty (20) feet.
11.38.800 Interconnection of Dispersal Systems.
Upon installation of a new dispersal system, the new system shall be
interconnected with the existing system with an approved flow diversion device to allow
for the alternating use of the two dispersal systems.
11.38.810 Prohibition on the Use of See a e Pits for New
Construction.
A. The use of a seepage pit is prohibited for use with construction of onsite
wastewater treatment systems for new buildings with applications submitted after the
effective date of this ordinance, unless the system is equipped with additional treatment
that meets the requirements of a NOWTS.
HOA.102294191.1 26
B. Notwithstanding Section A, the use of a seepage pit in conjunction with a
conventional OWTS is permitted for new construction for single unit dwellings with four
(4) or fewer bedrooms.
11.38.820 Evidence of a Failing OWTS.
Whenever the Director is made aware that an OWTS is at risk of failing, the
Director shall send a letter directing the property owner to have the system evaluated by
a qualified contractor within seven (7) calendar days to determine whether the system
must be repaired or replaced. If the evaluation reveals that the system requires repair
or replacement the property owner shall:
A. Prevent any further discharges of sewage by having the system pumped
by a sewage pumper truck at a frequency that will prevent overflow.
B. Follow any directive issued by the Director that is necessary to protect
groundwater or prevent surfacing of sewage effluent.
C. Complete all repairs within a time determined by the Director.
1 1.38.830 When a NOWTS is Required.
A. A NOWTS is required to be installed for new construction when any of the
following conditions exist:
1. The percolation rate is faster than 5.12 gallons per square foot per
day for a replacement seepage pit.
2. A seepage pit is proposed for installation at a new building other
than a single unit dwelling with four (4) or fewer bedrooms.
HOA.102294191.1 27
3. The percolation rate for a leach field or leach bed system is faster
than one (1) MPI or greater than one (1) MPI but less than 4.9 MPI and groundwater is
within twenty (20) feet of the bottom of the dispersal system for a new or replacement
OWTS.
4. There is less than five (5) feet but at least two (2) feet of
continuous, natural, undisturbed soil beneath a dispersal system.
5. The property of the proposed system is within six hundred
(600) feet of an impaired water body that is listed for pathogens or nitrogen and no
established Total Maximum Daily Load (TMDL) for that water body is present.
6. The property of the proposed system is within the area defined by
an Advanced Protection Management Program (APMP) established by a TMDL
implementation plan.
B. A NOWTS proposed to be installed in the areas of the Antelope Valley
within the jurisdiction of the Lahontan Regional Water Quality Control Board (LRWQCB)
shall not be required to include a disinfection system.
C. In addition to the circumstances listed in A above, the Director may require
the installation of a NOWTS as a condition of a variance to setback requirements for
repair of a failed existing system. All variances shall comply with the OWTS
requirements and procedures to the maximum extent possible.
HoA.102294191.1 28
11.38.840 Minimum Conditions for Authorization to Install a
NOWTS.
All NOWTS shall meet the following minimum conditions:
A. The system shall be certified by an agency accredited by the American
National Standards Institute (ANSI) as meeting the National Sanitation Foundation
(NSF) Standard two hundred forty-five (245) or the system shall be approved by the
Director after completing a demonstration test described in the OWTS requirements and
procedures.
B. NOWTS requiring a disinfection system, shall be certified by an ANSI
accredited agency as meeting NSF Standard forty-six (46) for disinfection devices.
C. The septic tank shall be part of the NSF certified system, certified by the
IAPMO, or evaluated by the local plumbing official and determined to be Plumbing Code
equivalent.
D. The NOWTS shall be equipped with a visual or audible alarm as well as a
telemetric alarm that notifies the owner and the service provider of the NOWTS in the
event of system malfunction. If the property requiring an NOWTS is in a location where
telemetric monitoring is not possible, more frequent physical inspections are required
per Section 11.38.880.
E. The owner shall record a covenant against the title of the property meeting
the requirements of Section 11.38.890.
F. The owner, prior to approval of the NOWTS, shall enter into and maintain
in effect at all times throughout the operational life of the system, a contract signed by
HOA.1 02294181.1 29
both the property owner and a service provider certified by the components'
manufacturer. The contract shall include:
1. Telemetric monitoring of the system for component failures or
quarterly inspections of the disinfection system when telemetric monitoring is not
available.
2. Annual inspections of the system or more frequent routine
maintenance as recommended by the manufacturer when telemetric monitoring is
available.
3. Any required sampling of influent and effluent based on the system
type, age, and location.
G. The Director may, at any reasonable time, require samples to be taken
from the NOWTS while a department representative and/or a contractor or agent of the
department is present.
11.38.850 Performance Standards for NOWTS.
A. All NOWTS shall be designed to produce effluent that meets the following
criteria:
1. Total Suspended Solids of less than thirty (30) mg.
2. Biological Oxygen Demand five (5) day average (BODS) of less
than thirty (30) mg/I.
3. PH not less than 6.0 or greater than 9.0.
B. NOWTS treatment of nitrogen must result in a fifty (50) percent reduction
in Total Nitrogen.
HOA.102294191.1 30
C. NOWTS provide disinfection that does not exceed a fecal coliform content
of two hundred (200) per one hundred (100) milliliters using the Most Probable Number
(MPN) analytical method with a minimum detection limit of 2.2 MPN,
11.38.860 NOWTS Permit.
A. A permit shall be issued by the Director for the operation of a NOWTS
upon the approval of the system. A permit shall be valid for the location, type of system,
and conditions of the approval, unless suspended or revoked by the Director.
B. The permit fee shall be collected in accordance with Los Angeles County
Code Title 8, Sections 8.04.950 — 8.04.995.
C. A permit may be suspended or revoked by the Director for the following
reasons:
The NOWTS is contributing to the contamination of groundwater,
surface water, or resulting in the surfacing of effluent, and the owner has not returned
the NOWTS to operating condition within the time required by the Director.
2. The owner does not submit records of maintenance inspections or
results of effluent testing as required by this ordinance within the time required by the
Director.
D. It shall be a violation of this code to operate a NOWTS for which the
permit has been suspended or revoked.
E. The owner of the NOWTS shall make the system available within five
(5) calendar days for inspection upon notice by the department.
HOA.102294191.1 31
11.38.870----..... Maintenance Required and Reporting Results.
A. The property owner shall have the NOWTS inspected and serviced at the
rate set by the manufacturer as set forth in the manufacturer's operation and
maintenance manual or at least annually, by a service provider certified by the
manufacturer.
B. If the property is located in an area where telemetric monitoring is not
possible, the property owner shall cause the NOWTS to be inspected monthly by the
NOWTS owner as directed and instructed by a NOWTS service provider, and quarterly
by the NOWTS service provider, in order to determine whether the NOWTS is operating
as required.
C. The service provider shall submit copies of all inspection and maintenance
reports to the Director within thirty (30) days of any inspection or maintenance of the
NOWTS.
0 Influent and Effluent Testing and Reporting
Requirements.
Owners of NOWTS shall have their maintenance service provider collect and
submit samples for laboratory testing of influent and effluent to determine if the system
meets the performance standards specified in Section 11.38.850. The frequency of this
sampling shall comply with the following table.
Type of System
When Testing is Required
All NOWTS
After completions of repairs (Within seven
(7) days)
HOA.1022941 91.1 32
NOWTS installed in within six hundred
Annually with telemetric monitoring or
600) feet of a water body impaired for
Quarterly without telemetric monitoring
pathogenic bacteria or in response to a
MDL for bacteria
NOWTS larger than a single family
Annually
residence located in the Antelope Valley
The. service provider shall submit a copy of the laboratory analysis of effluent
testing to the Director within thirty (30) days of the date the results are provided to the
owner or service provider by the laboratory.
11.38.890 Covenant.
A. The approval of a NOWTS for a future expansion area requires
recordation of a covenant through the County office of the Registrar-Recorder/County
Clerk.
B. The installation of a NOWTS requires recordation of a covenant through
the County Office of the Registrar-RecorderlCounty Clerk.
C. The covenant shall inform all future prospective owners of the property of
the following:
1. A NOWTS is installed on the property.
2. Operation and maintenance of the NOWTS is required to comply
with State and local laws.
HOA.102294191.1 33
3. A service agreement for maintenance and monitoring is required at
all times with an approved servicing company.
4. The Director must be notified in writing within thirty (30) days of a
change of servicing company.
5. Maintenance records and effluent testing results must be submitted
to the Director within thirty (30) days of annual servicing.
6. The owner is required to repair the system and conduct effluent
testing of the system if inspection reveals that it is not in compliance with State or local
laws.
7. The owner is required to replace the NOWTS at their own expense
if it cannot be repaired to be in compliance.
8. The owner agrees to allow inspection of the NOWTS within five
(5) calendar days, upon notice by the Director, absent an emergency.
SECTION 32. Part 6, of Chapter 11.38 of the Los Angeles County Code is
hereby added to read as follows:
Part 6 Sewage PumpingVehicles
11.38.900 Seepage/Sewage Pumping Vehicle Operator.
An operator of a seepage/sewage pumping vehicle is required to register with the
local jurisdiction as per California Health and Safety Code Sections 117400-117450. A
public health license shall be issued to the owner of a seepage/sewage pumping vehicle
when that person has demonstrated that either the owner or an employee of the owner
has adequate knowledge to train other employees as described in Section 11.38.910.
H0A.102294191 A 34
A change of address of the owner including a member of a partnership that is
registered and of the place of business thereof shall be reported in writing by the owner
to the Director within two (2) days after the change of address.
11.38.914 Adequate Knowledge.
A public health license shall only be issued after the applicant or his or her
representative submits demonstrates adequate knowledge of the following topics:
A. Knowledge of the equipment to be used.
B. The applicant's knowledge of sanitary principles and of the laws and
ordinances affecting human health or nuisances, including the factors that evidence a
failing OWTS and appropriate locations for disposal of septage. Proper use of personal
protective equipment.
C. Clean up of spills or discharges of sewage from failed plumbing systems.
Knowledge may be demonstrated by submitting curriculum for the training of new
staff to the Director for approval, completion of a training course from a professional
organization, such as the California Onsite Water Association (COWA), or an approved
public entity or an online course acceptable to the Director. The individual receiving the
training shall be designated as the trainer for his or her organization. The applicant
shall maintain a trainer as part of the organization. If the trainer leaves the organization,
it has ninety (90) days to obtain a new trainer.
The owner shall be responsible for ensuring that employees responsible for the
clean out of septic tanks, chemical toilets, cesspools and sewage seepage pits are
properly trained before they work independently, and get trained annually thereafter.
HOA.102294191.1 35
The owner shall have available for the Director upon request the name of the
trainer and records of the employee's annual trainings.
11.38.920 Required for See a elSewa a Pumpina Vehicle.
No person shall operate a sewage pumping vehicle without first making
application and securing a license from the Director.
11.38.930 Application and issuance Conditions
A. Applications for seepage/sewage pumping vehicles shall be made on
forms provided for that purpose by the Director. All applicable fees, shall be paid at the
time of the application.
B. The application shall include the Vehicle Identification Number (VIN), the
year and make of vehicle, the vehicle license number, the tank capacity, the owner
information, the location where the vehicle shall be stored, and any other data required
by the Director.
C. Upon receipt of an application, the Director shall make an inspection of the
seepage/sewage pumping vehicle. If the applicant has complied with all applicable laws
and regulations, and the vehicle meets the requirements of the inspection, the Director
shall approve the application, and issue an annual license.
1 1.38.940 Suspension and Revocation of License.
The Director may suspend or revoke the license of an operator of one (1) or
more seepagelsewage pumping vehicles or the license of an individual
seepage/sewage pumping vehicle.
HOA.1022941 si.1 36
The Director may suspend or revoke a license issued to an operator of one (1) or
more sewage pumping vehicle for any of the following violations:
A. Discharge of sewage or the contents of one (1) or more trucks in a
location other than one approved by the Director.
B. Failure to submit quarterly reports identifying all of the locations serviced
and where the contents of the truck were discharged.
C. Failure to report locations that evidence conditions of a failing OWTS, a
cesspool, or an earthen pit privy.
The Director may suspend or revoke a license issued to a sewage pumping
vehicle for violations of this code, including, leakage of sewage from the tank, valves,
piping, or other equipment that may discharge to the ground surface.
11.38.950 Identification of Vehicle.
Seepage/Sewage pumping vehicles shall be identified with the business name,
City, State, Zip Code and phone number on both sides of vehicle. The business name
shall be in letters and numbers at least three (3) inches in height, additional information
shall be at least one (1) inch in height and all letters and numbers shall be of a color
contrasting to the vehicle. The public health registration number shall be located on the
rear of the vehicle in letters and numbers at least three (3) inches high and of a color
contrasting to the vehicle.
11.38.960 Construction of Seepage/Sewage_Cl_eaniing Vehicle.
A seepage/sewage pumping vehicle shall be constructed and maintained at all
times with the following components in good working order:
HOA.102294191.1 37
A. A water tight tank, valves, piping, pumps and equipment maintained free
from leakage.
B. A hose for flushing contaminated areas.
C. A quick release valve on the discharge outlet.
D. A metal sleeve or other suitable device provided to reach from discharge
outlet to manhole.
E. Tight fitting covers for tank openings.
11.38.970 Seepage/Sewage Pumping Vehicle fperation
Requirements.
A. All contents of the sewage holding tank shall be deposited in an approved
County Sanitation District location or at a location approved by the Director.
B. Personal protective equipment including gloves, goggles, and boots shall
be provided to all employees working with sewage or septage.
C. A sewage spill kit shall be maintained on the vehicle for use in cleaning -up
any sewage spills. The sewage spill kit shall contain at a minimum:
1. Containment barriers to prevent the spill from entering a storm
rIMI
2. Absorbent material.
3. A shovel.
4. Garbage bags.
5. Liquid disinfectant and powdered lime.
D. The vehicle registration shall be maintained on the vehicle.
HOA.102294191.1 38
E. The vehicle exterior shall be maintained free of sewage or other waste
material.
11.38.980 See a e/Sews a Pumping Vehicle Service Reports.
A. Seepage/sewage pumping vehicles are required to file with the Director a
quarterly report specifying all of the following:
The name and address of the owner or tenant of each and every
one of the premises where a septic tank, cesspool, or sewage seepage pit has been
cleaned out by the registrant, his or her employees, or by others on his or her behalf
and the date of each cleaning.
2. The location where the cleanings are disposed of.
3. Discharges of waste that may result in violation of laws or
ordinances required to be known by the registrant pursuant to Health and Safety Code
Section 117420.
B. OWTS showing symptoms of failure must be reported to the Director
within twenty-four (24) hours of pumping. Factors evidencing a failing OWTS are
identified in Section 11.38.042.
[804420RRCCj
HOA.102294191.1 39
to
co
co
Water Qualltg Control Poling for Siting,
Design, Opercifion, and Maintenance of
Omits Wastewater Treatment Sgstems
June 19, 2012
O�
Water Boards
STATE WATER RESOURCES CONTROL BOARD
REGIONAL WATER QUALITY CONTROL BOARDS
CaIIEPA
State of California
Edmund G. Brown Jr., Governor
California Environmental Protection Agency
Matthew Rodriquez, Secretary
State Water Resources Control Board
http://www.waterboards.ca.gov
Charles R. Hoppin, Chair
Frances Spivy-Weber, Vice Chair
Tam M. Doduc, Member
Steven Moore, Member
Thomas Howard, Executive Director
Jonathan Bishop, Chief Deputy Director
Caren Trgovcich, Chief Deputy Director
Adopted by the State Water Resources Control Board on June 19, 2012
Approved by the Office of Administrative Law on November 13, 2012
Effective Date of the Policy: May 13, 2013
Preamble — Purpose and Scope — Structure of the Policy
Preamble
Onsite wastewater treatment systems (OWTS) are useful and necessary structures that
allow habitation at locations that are removed from centralized wastewater treatment
systems. When properly sited, designed, operated, and maintained, OWTS treat
domestic wastewater to reduce its polluting impact on the environment and most
importantly protect public health. Estimates for the number of installations of OWTS in
California at the time of this Policy are that more than 1.2 million systems are installed
and operating. The vast majority of these are functioning in a satisfactory manner and
meeting their intended purpose.
However there have been occasions in California where OWTS for a varied list of
reasons have not satisfactorily protected either water quality or public health. Some
instances of these failures are related to the OWTS not being able to adequately treat
and dispose of waste as a result of poor design or improper site conditions. Others
have occurred where the systems are operating as designed but their densities are
such that the combined effluent resulting from multiple systems is more than can be
assimilated into the environment. From these failures we must learn how to improve
our usage of OWTS and prevent such failures from happening again.
As California's population continues to grow, and we see both increased rural housing
densities and the building of residences and other structures in more varied terrain than
we ever have before, we increase the risks of causing environmental damage and
creating public health risks from the use of OWTS. What may have been effective in
the past may not continue to be as conditions and circumstances surrounding particular
locations change. So necessarily more scrutiny of our installation of OWTS is
demanded of all those involved, while maintaining an appropriate balance of only the
necessary requirements so that the use of OWTS remains viable.
Purpose and Scope of the Policy
The purpose of this Policy is to allow the continued use of OWTS, while protecting water
quality and public health. This Policy recognizes that responsible local agencies can
provide the most effective means to manage OWTS on a routine basis. Therefore as
an important element, it is the intent of this policy to efficiently utilize and improve upon
where necessary existing local programs through coordination between the State and
local agencies. To accomplish this purpose, this Policy establishes a statewide, risk-
based, tiered approach for the regulation and management of OWTS installations and
replacements and sets the level of performance and protection expected from OWTS.
In particular, the Policy requires actions for water bodies specifically identified as part
this Policy where OWTS contribute to water quality degradation that adversely affect
beneficial uses.
This Policy only authorizes subsurface disposal of domestic strength, and in limited
instances high strength, wastewater and establishes minimum requirements for the
permitting, monitoring, and operation of OWTS for protecting beneficial uses of waters
Preamble — Purpose and Scope — Structure of the Policy
of the State and preventing or correcting conditions of pollution and nuisance. And
finally, this Policy also conditionally waives the requirement for owners of OWTS to
apply for and receive Waste Discharge Requirements in order to operate their systems
when they meet the conditions set forth in the Policy. Nothing in this Policy supersedes
or requires modification of Total Maximum Daily Loads or Basin Plan prohibitions of
discharges from OWTS.
This Policy also applies to OWTS on federal, state, and Tribal lands to the extent
authorized by law or agreement.
Structure of the Policy
This Policy is structured into ten major parts:
Definitions
Definitions for all the major terms used in this Policy are provided within this part and
wherever used in the Policy the definition given here overrides any other possible
definition.
[Section 1
Responsibilities and Duties
Implementation of this Policy involves individual OWTS owners; local agencies, be they
counties, cities, or any other subdivision of state government with permitting powers
over OWTS; Regional Water Quality Control Boards; and the State Water Resources
Control Board.
[Sections 2 3 4 and 51
Tier 0 — Existing OWTS
Existing OWTS that are properly functioning, and do not meet the conditions of failing
systems or otherwise require corrective action (for example, to prevent groundwater
impairment) as specifically described in Tier 4, and are not determined to be
contributing to an impairment of surface water as specifically described in Tier 3, are
automatically included in Tier 0.
[Section 6
Tier 1 — Low -Risk New or Replacement OWTS
New or replacement OWTS that meet low risk siting and design requirements as
specified in Tier 1, where there is not an approved Local Agency Management Program
per Tier 2.
[Sections 7 and 8]
Tier 2 — Local Agency Management Program for New or Replacement OWTS
California is well known for its extreme range of geological and climatic conditions. As
such, the establishment of a single set of criteria for OWTS would either be too
restrictive so as to protect for the most sensitive case, or would have broad allowances
that would not be protective enough under some circumstances. To accommodate this
2
Preamble — Purpose and Scope — Structure of the Policy
extreme variance, local agencies may submit management programs ("Local Agency
Management Programs") for approval, and upon approval then manage the installation
of new and replacement OWTS under that program.
Local Agency Management Programs approved under Tier 2 provide an alternate
method from Tier 1 programs to achieve the same policy purpose, which is to protect
water quality and public health. In order to address local conditions, Local Agency
Management Programs may include standards that differ from the Tier 1 requirements
for new and replacement OWTS contained in Sections 7 and 8. As examples, a Local
Agency Management Program may authorize different soil characteristics, usage of
seepage pits, and different densities for new developments. Once the Local Agency
Management Program is approved, new and replacement OWTS that are included
within the Local Agency Management Program may be approved by the Local Agency.
A Local Agency, at its discretion, may include Tier 1 standards within its Tier 2 Local
Agency Management Program for some or all of its jurisdiction. However, once a Local
Agency Management Program is approved, it shall supersede Tier 1 and all future
OWTS decisions will be governed by the Tier 2 Local Agency Management Program
until it is modified, withdrawn, or revoked.
[Section 9
Tier 3 — Impaired Areas
Existing, new, and replacement OWTS that are near impaired water bodies may be
addressed by a TMDL and its implementation program, or special provisions contained
in a Local Agency Management Program. If there is no TMDL or special provisions,
new or replacement OWTS within 600 feet of impaired water bodies listed in Attachment
2 must meet the specific requirements of Tier 3.
[Section 10]
Tier 4 — OWTS Requiring Corrective Action
OWTS that require corrective action or are either presently failing or fail at any time
while this Policy is in effect are automatically included in Tier 4 and must follow the
requirements as specified.
[Section 11 ]
Conditional Waiver of Waste Discharge Requirements
The requirement to submit a report of waste discharge for discharges from OWTS that
are in conformance with this policy is waived.
[Section 12]
Effective Date
When this Policy becomes effective.
[Section 13]
Financial Assistance
Procedures for local agencies to apply for funds to establish low interest loan programs
for the assistance of OWTS owners in meeting the requirements of this Policy.
[Section 14]
3
Preamble — Purpose and Scope — Structure of the Policy
Attachment 1
AB 885 Regulatory Program Timelines.
Attachment 2
Tables 4 and 5 specifically identify those impaired water bodies that have Tier 3
requirements and must have a completed TMDL by the date specified.
Attachment 3
Table 6 shows where one Regional Water Board has been designated to review and, if
appropriate, approve new Local Agency Management Plans for a local agency that is
within multiple Regional Water Boards' jurisdiction.
What Tier Applies to my OWTS?
Existing OWTS that conform to the requirements for Tier 0 will remain in Tier 0 as long
as they continue to meet those requirements. An existing OWTS will temporarily move
from Tier 0 to Tier 4 if it is determined that corrective action is needed. The existing
OWTS will return to Tier 0 once the corrective action is completed if the repair does not
qualify as major repair under Tier 4. Any major repairs conducted as corrective action
must comply with Tier 1 requirements or Tier 2 requirements, whichever are in effect for
that local area. An existing OWTS will move from Tier 0 to Tier 3 if it is adjacent to an
impaired water body listed on Attachment 2, or is covered by a TMDL implementation
plan.
In areas with no approved Local Agency Management Plan, new and replacement
OWTS that conform to the requirements of Tier 1 will remain in Tier 1 as long as they
continue to meet those requirements. A new or replacement OWTS will temporarily
move from Tier 1 to Tier 4 if it is determined that corrective action is needed. The new
or replacement OWTS will return to Tier 1 once the corrective action is completed. A
new or replacement OWTS will move from Tier 1 to Tier 3 if it is adjacent to an impaired
water body, or is covered by a TMDL implementation plan.
In areas with an approved Local Agency Management Plan, new and replacement
OWTS that conform to the requirements of the Tier 2 Local Agency Management Plan
will remain in Tier 2 as long as they continue to meet those requirements. A new or
replacement OWTS will temporarily move from Tier 2 to Tier 4 if it is determined that
corrective action is needed. The new or replacement OWTS will return to Tier 2 once
the corrective action is completed. A new or replacement OWTS will move from Tier 2
to Tier 3 if it is adjacent to an impaired water body, or is covered by a TMDL
implementation plan, or is covered by special provisions for impaired water bodies
contained in a Local Agency Management Program.
12
Preamble — Purpose and Scope — Structure of the Policy
Existing, new, and replacement OWTS in specified areas adjacent to water bodies that
are identified by the State Water Board as impaired for pathogens or nitrogen and listed
in Attachment 2 are in Tier 3. Existing, new, and replacement OWTS covered by a
TMDL implementation plan, or covered by special provisions for impaired water bodies
contained in a Local Agency Management Program are also in Tier 3. These OWTS
will temporarily move from Tier 3 to Tier 4 if it is determined that corrective action is
needed. The new or replacement OWTS will return to Tier 3 once the corrective action
is completed.
Existing, new, and replacement OWTS that do not conform with the requirements to
receive coverage under any of the Tiers (e.g., existing OWTS with a projected flow of
more than 10,000 gpd) do not qualify for this Policy's conditional waiver of waste
discharge requirements, and will be regulated separately by the applicable Regional
Water Board.
5
Definitions
1.0 Definitions. The following definitions apply to this Policy:
"303 (d) list" means the same as "Impaired Water Bodies."
"At -grade system" means an OWTS dispersal system with a discharge point located
at the preconstruction grade (ground surface elevation). The discharge from an at -
grade system is always subsurface.
"Average annual rainfall" means the average of the annual amount of precipitation for
a location over a year as measured by the nearest National Weather Service station
for the preceding three decades. For example the data set used to make a
determination in 2012 would be the data from 1981 to 2010.
"Basin Plan" means the same as "water quality control plan" as defined in Division 7
(commencing with Section 13000) of the Water Code. Basin Plans are adopted by
each Regional Water Board, approved by the State Water Board and the Office of
Administrative Law, and identify surface water and groundwater bodies within each
Region's boundaries and establish, for each, its respective beneficial uses and water
quality objectives. Copies are available from the Regional Water Boards,
electronically at each Regional Water Boards website, or at the State Water Board's
Plans and Policies web page (http://www.waterboards.ca.gov/plans policies/).
"Bedrock" means the rock, usually solid, that underlies soil or other unconsolidated,
surficial material.
"CEDEN" means California Environmental Data Exchange Network and information
about it is available at the State Water Boards website or
http://www.ceden.org/index.shtml.
"Cesspool" means an excavation in the ground receiving domestic wastewater,
designed to retain the organic matter and solids, while allowing the liquids to seep
into the soil. Cesspools differ from seepage pits because cesspool systems do not
have septic tanks and are not authorized under this Policy. The term cesspool does
not include pit -privies and out -houses which are not regulated under this Policy.
"Clay" means a soil particle; the term also refers to a type of soil texture. As a soil
particle, clay consists of individual rock or mineral particles in soils having diameters
<0.002 mm. As a soil texture, clay is the soil material that is comprised of 40
percent or more clay particles, not more than 45 percent sand and not more than 40
percent silt particles using the USDA soil classification system.
"Cobbles" means rock fragments 76 mm or larger using the USDA soil classification
systems.
"Dispersal system" means a leachfield, seepage pit, mound, at -grade, subsurface drip
field, evapotranspiration and infiltration bed, or other type of system for final
wastewater treatment and subsurface discharge.
9
Definitions
"Domestic wastewater" means wastewater with a measured strength less then high-
strength wastewater and is the type of wastewater normally discharged from, or
similar to, that discharged from plumbing fixtures, appliances and other household
devices including, but not limited to toilets, bathtubs, showers, laundry facilities,
dishwashing facilities, and garbage disposals. Domestic wastewater may include
wastewater from commercial buildings such as office buildings, retail stores, and
some restaurants, or from industrial facilities where the domestic wastewater is
segregated from the industrial wastewater. Domestic wastewater may include
incidental RV holding tank dumping but does not include wastewater consisting of a
significant portion of RV holding tank wastewater such as at RV dump stations.
Domestic wastewater does not include wastewater from industrial processes.
"Dump Station" means a facility intended to receive the discharge of wastewater from
a holding tank installed on a recreational vehicle. A dump station does not include a
full hook-up sewer connection similar to those used at a recreational vehicle park.
"Domestic well" means a groundwater well that provides water for human
consumption and is not regulated by the California Department of Public Health.
"Earthen material" means a substance composed of the earth's crust (i.e. soil and
rock).
"EDF" see "electronic deliverable format."
"Effluent" means sewage, water, or other liquid, partially or completely treated or in its
natural state, flowing out of a septic tank, aerobic treatment unit, dispersal system,
or other OWTS component.
"Electronic deliverable format" or "EDF" means the data standard adopted by the
State Water Board for submittal of groundwater quality monitoring data to the State
Water Board's internet-accessible database system Geotracker
(http://geotracker.waterboards.ca.gov/).
"Escherichia coli" means a group of bacteria predominantly inhabiting the intestines of
humans or other warm-blooded animals, but also occasionally found elsewhere.
Used as an indicator of human fecal contamination.
"Existing OWTS" means an OWTS that was constructed and operating prior to the
effective date of this Policy, and OWTS for which a construction permit has been
issued prior to the effective date of the Policy.
"Flowing water body" means a body of running water flowing over the earth in a
natural water course, where the movement of the water is readily discernible or if
water is not present it is apparent from review of the geology that when present it
does flow, such as in an ephemeral drainage, creek, stream, or river.
"Groundwater" means water below the land surface that is at or above atmospheric
pressure.
7
Definitions
"High-strength wastewater" means wastewater having a 30 -day average
concentration of biochemical oxygen demand (BOD) greater than 300 milligrams -
per -liter (mg/L) or of total suspended solids (TSS) greater than 330 mg/L or a fats,
oil, and grease (FOG) concentration greater than 100 mg/L prior to the septic tank or
other OWTS treatment component.
"IAPMO" means the International Association of Plumbing and Mechanical Officials.
"Impaired Water Bodies" means those surface water bodies or segments thereof that
are identified on a list approved first by the State Water Board and then approved by
US EPA pursuant to Section 303(d) of the federal Clean Water Act.
"Local agency" means any subdivision of state government that has responsibility for
permitting the installation of and regulating OWTS within its jurisdictional boundaries;
typically a county, city, or special district.
"Major repair" means either: (1) for a dispersal system, repairs required for an OWTS
dispersal system due to surfacing wastewater effluent from the dispersal field and/or
wastewater backed up into plumbing fixtures because the dispersal system is not
able to percolate the design flow of wastewater associated with the structure served,
or (2) for a septic tank, repairs required to the tank for a compartment baffle failure
or tank structural integrity failure such that either wastewater is exfiltrating or
groundwater is infiltrating.
"Mottling" means a soil condition that results from oxidizing or reducing minerals due
to soil moisture changes from saturated to unsaturated over time. Mottling is
characterized by spots or blotches of different colors or shades of color (grays and
reds) interspersed within the dominant color as described by the USDA soil
classification system. This soil condition can be indicative of historic seasonal high
groundwater level, but the lack of this condition may not demonstrate the absence of
groundwater.
"Mound system" means an aboveground dispersal system (covered sand bed with
effluent leachfield elevated above original ground surface inside) used to enhance
soil treatment, dispersal, and absorption of effluent discharged from an OWTS
treatment unit such as a septic tank. Mound systems have a subsurface discharge.
"New OWTS" means an OWTS permitted after the effective date of this Policy.
"NSF" means NSF International (a.k.a. National Sanitation Foundation), a not for profit,
non-governmental organization that develops health and safety standards and
performs product certification.
"Oil/grease interceptor" means a passive interceptor that has a rate of flow exceeding
50 gallons -per -minute and that is located outside a building. Oil/grease interceptors
are used for separating and collecting oil and grease from wastewater.
0
Definitions
"Onsite wastewater treatment system(s)" (OWTS) means individual disposal
systems, community collection and disposal systems, and alternative collection and
disposal systems that use subsurface disposal. The short form of the term may be
singular or plural. OWTS do not include "graywater" systems pursuant to Health and
Safety Code Section 17922.12.
"Percolation test" means a method of testing water absorption of the soil. The test is
conducted with clean water and test results can be used to establish the dispersal
system design.
"Permit" means a document issued by a local agency that allows the installation and
use of an OWTS, or waste discharge requirements or a waiver of waste discharge
requirements that authorizes discharges from an OWTS.
"Person" means any individual, firm, association, organization, partnership, business
trust, corporation, company, State agency or department, or unit of local government
who is, or that is, subject to this Policy.
"Pit -privy" (a.k.a. outhouse, pit -toilet) means self-contained waterless toilet used for
disposal of non -water carried human waste; consists of a shelter built above a pit in
the ground into which human waste falls.
"Policy" means this Policy for Siting, Design, Operation and Management of OWTS.
"Pollutant" means any substance that alters water quality of the waters of the State to
a degree that it may potentially affect the beneficial uses of water, as listed in a
Basin Plan.
"Projected flows" means wastewater flows into the OWTS determined in accordance
with any of the applicable methods for determining average daily flow in the USEPA
Onsite Wastewater Treatment System Manual, 2002, or for Tier 2 in accordance
with an approved Local Agency Management Program.
"Public Water System" is a water system regulated by the California Department of
Public Health or a Local Primacy Agency pursuant to Chapter 12, Part 4, California
Safe Drinking Water Act, Section 116275 (h) of the California Health and Safety
Code.
"Public Water Well" is a ground water well serving a public water system. A spring
which is not subject to the California Surface Water Treatment Rule (SWTR), CCR,
Title 22, sections 64650 through 64666 is a public well.
"Qualified professional" means an individual licensed or certified by a State of
California agency to design OWTS and practice as professionals for other
associated reports, as allowed under their license or registration. Depending on the
work to be performed and various licensing and registration requirements, this may
include an individual who possesses a registered environmental health specialist
certificate or is currently licensed as a professional engineer or professional
geologist. For the purposes of performing site evaluations, Soil Scientists certified by
the Soil Science Society of America are considered qualified professionals. A local
agency may modify this definition as part of its Local Agency Management Program.
9
Definitions
"Regional Water Board" is any of the Regional Water Quality Control Boards
designated by Water Code Section 13200. Any reference to an action of the
Regional Water Board in this Policy also refers to an action of its Executive Officer,
including the conducting of public hearings, pursuant to any general or specific
delegation under Water Code Section 13223.
"Replacement OWTS" means an OWTS that has its treatment capacity expanded, or
its dispersal system replaced or added onto, after the effective date of this Policy.
"Sand" means a soil particle; this term also refers to a type of soil texture. As a soil
particle, sand consists of individual rock or mineral particles in soils having
diameters ranging from 0.05 to 2.0 millimeters. As a soil texture, sand is soil that is
comprised of 85 percent or more sand particles, with the percentage of silt plus 1.5
times the percentage of clay particles comprising less than 15 percent.
"Seepage pit" means a drilled or dug excavation, three to six feet in diameter, either
lined or gravel filled, that receives the effluent discharge from a septic tank or other
OWTS treatment unit for dispersal.
"Septic tank" means a watertight, covered receptacle designed for primary treatment
of wastewater and constructed to:
1. Receive wastewater discharged from a building;
2. Separate settleable and floating solids from the liquid;
3. Digest organic matter by anaerobic bacterial action;
4. Store digested solids; and
5. Clarify wastewater for further treatment with final subsurface discharge.
"Service provider" means a person capable of operating, monitoring, and maintaining
an OWTS in accordance to this Policy.
"Silt" means a soil particle; this term also refers to a type of soil texture. As a soil
particle, silt consists of individual rock or mineral particles in soils having diameters
ranging from between 0.05 and 0.002 mm. As a soil texture, silt is soil that is
comprised as approximately 80 percent or more silt particles and not more than 12
percent clay particles using the USDA soil classification system.
"Single-family dwelling unit" means a structure that is usually occupied by just one
household or family and for the purposes of this Policy is expected to generate an
average of 250 gallons per day of wastewater.
"Site" means the location of the OWTS and, where applicable, a reserve dispersal area
capable of disposing 100 percent of the design flow from all sources the OWTS is
intended to serve.
"Site Evaluation" means an assessment of the characteristics of the site sufficient to
determine its suitability for an OWTS to meet the requirements of this Policy.
10
Definitions
"Soil" means the naturally occurring body of porous mineral and organic materials on
the land surface, which is composed of unconsolidated materials, including sand -
sized, silt -sized, and clay -sized particles mixed with varying amounts of larger
fragments and organic material. The various combinations of particles differentiate
specific soil textures identified in the soil textural triangle developed by the United
States Department of Agriculture (USDA) as found in Soil Survey Staff, USDA; Soil
Survey Manual, Handbook 18, U.S. Government Printing Office, Washington, DC,
1993, p. 138. For the purposes of this Policy, soil shall contain earthen material of
particles smaller than 0.08 inches (2 mm) in size.
"Soil Structure" means the arrangement of primary soil particles into compound
particles, peds, or clusters that are separated by natural planes of weakness from
adjoining aggregates.
"Soil texture" means the soil class that describes the relative amount of sand, clay, silt
and combinations thereof as defined by the classes of the soil textural triangle
developed by the USDA (referenced above).
"State Water Board" is the State Water Resources Control Board
"Supplemental treatment" means any OWTS or component of an OWTS, except a
septic tank or dosing tank, that performs additional wastewater treatment so that the
effluent meets a predetermined performance requirement prior to discharge of
effluent into the dispersal field.
"SWAMP" means Surface Water Ambient Monitoring Program and more information is
available at: http://www.waterboards.ca.gov/water issues/programs/swamp/
"Telemetric" means the ability to automatically measure and transmit OWTS data by
wire, radio, or other means.
"TMDL" is the acronym for "total maximum daily load." Section 303(d)(1) of the Clean
Water Act requires each State to establish a TMDL for each impaired water body to
address the pollutant(s) causing the impairment. In California, TMDLs are usually
adopted as Basin Plan amendments and contain implementation plans detailing how
water quality standards will be attained.
"Total coliform" means a group of bacteria consisting of several genera belonging to
the family Enterobacteriaceae, which includes Escherichia coli bacteria.
"USDA" means the U.S. Department of Agriculture.
"Waste discharge requirement" or "WDR" means an operation and discharge permit
issued for the discharge of waste pursuant to Section 13260 of the California Water
Code.
11
Responsibilities and Duties
Responsibilities and Duties
2.0 OWTS Owners Responsibilities and Duties
2.1 All new, replacement, or existing OWTS within an area that is subject to a
Basin Plan prohibition of discharges from OWTS, must comply with the
prohibition. If the prohibition authorizes discharges under specified conditions,
the discharge must comply with those conditions and the applicable provisions
of this Policy.
2.2 Owners of OWTS shall adhere to the requirements prescribed in local codes
and ordinances. Owners of new and replacement OWTS covered by this
Policy shall also meet the minimum standards contained in Tier 1, or an
alternate standard provided by a Local Agency Management Program per Tier
2, or shall comply with the requirements of Tier 3 if near an impaired water
body and subject to Tier 3, or shall provide corrective action for their OWTS if
their system meets conditions that place it in Tier 4.
2.3 Owners of OWTS shall comply with any and all permitting conditions imposed
by a local agency that do not directly conflict with this Policy, including any
conditions that are more stringent than required by this Policy.
2.4 To receive coverage under this Policy and the included waiver of waste
discharges, OWTS shall only accept and treat flows of domestic wastewater. In
addition, OWTS that accept high-strength wastewater from commercial food
service buildings are covered under this Policy and the waiver of waste
discharge requirements if the wastewater does not exceed 900 mg/L BOD and
there is a properly sized and functioning oil/grease interceptor (a.k.a grease
trap).
2.5 Owners of OWTS shall maintain their OWTS in good working condition
including inspections and pumping of solids as necessary, or as required by
local ordinances, to maintain proper function and assure adequate treatment.
2.6 The following owners of OWTS shall notify the Regional Water Board by
submitting a Report of Waste Discharge for the following:
2.6.1 a new or replacement OWTS that does not meet the conditions and
requirements set forth in either a Local Agency Management Program if
one is approved, an existing local program if it is less than 60 months from
the effective date of the Policy and a Local Agency Management Program
is not yet approved, or Tier 1 if no Local Agency Management Program
has been approved and it is more than 60 months after the effective date
of this Policy;
2.6.2 any OWTS, not under individual waste discharge requirements or a waiver
of individual waste discharge requirements issued by a Regional Water
Board, with the projected flow of over 10,000 gallons -per -day;
12
Responsibilities and Duties
2.6.3 any OWTS that receives high-strength wastewater, unless the waste
stream is from a commercial food service building;
2.6.4 any OWTS that receives high-strength wastewater from a commercial
food service building: (1) with a BOD higher than 900 mg/L, or (2) that
does not have a properly sized and functioning oil/grease interceptor.
2.7 All Reports of Waste Discharge shall be accompanied by the required
application fee pursuant to California Code of Regulations, title 23, section 2200.
3.0 Local Agency Requirements and Responsibilities
3.1 Local agencies, in addition to implementing their own local codes and
ordinances, shall determine whether the requirements within their local
jurisdiction will be limited to the water quality protection afforded by the
statewide minimum standards in Tier 0, Tier 1, Tier 3, and Tier 4, or whether
the local agency will implement a Local Agency Management Program in
accordance with Tier 2. Except for Tier 3, local agencies may continue to
implement their existing OWTS permitting programs in compliance with the
Basin Plan in place at the effective date of the Policy until 60 months after the
effective date of this Policy, or approval of a Local Agency Management
Program, whichever comes first, and may make minor adjustments as
necessary that are in compliance with the applicable Basin Plan and this Policy.
Tier 3 requirements take effect on the effective date of this Policy. In the
absence of a Tier 2 Local Agency Management Program, to the extent that
there is a direct conflict between the applicable minimum standards and the
local codes or ordinances (such that it is impossible to comply with both the
applicable minimum standards and the local ordinances or codes), the more
restrictive standards shall govern.
3.2 If preferred, the local agency may at any time provide the State Water Board
and all affected Regional Water Board(s) written notice of its intent to regulate
OWTS using a Local Agency Management Program with alternative standards
as authorized in Tier 2 of this Policy. A proposed Local Agency Management
Program that conforms to the requirements of that Section shall be included
with the notice. A local agency shall not implement a program different than
the minimum standards contained in Tier 1 and 3 of this Policy after 60 months
from the effective date of this Policy until approval of the proposed Local
Agency Management Program is granted by either the Regional Water Board
or State Water Board. All initial program submittals desiring approval prior to
the 60 month limit shall be received no later than 36 months from the effective
date of this Policy. Once approved, the local agency shall adhere to the Local
Agency Management Program, including all requirements, monitoring, and
reporting. If at any time a local agency wishes to modify its Local Agency
Management Program, it shall provide the State Water Board and all affected
Regional Water Board(s) written notice of its intended modifications and will
continue to implement its existing Local Agency Management Program until the
modifications are approved.
13
Responsibilities and Duties
3.3 All local agencies permitting OWTS shall report annually to the Regional Water
Board(s). If a local agency's jurisdictional area is within the boundary of
multiple Regional Water Boards, the local agency shall send a copy of the
annual report to each Regional Water Board. The annual report shall include
the following information (organized in a tabular spreadsheet format) and
summarize whether any further actions are warranted to protect water quality or
public health:
3.3.1 number and location of complaints pertaining to OWTS operation and
maintenance, and identification of those which were investigated and how
they were resolved;
3.3.2 shall provide the applications and registrations issued as part of the local
septic tank cleaning registration program pursuant to Section 117400 et
seq. of the California Health and Safety Code;
3.3.3 number, location, and description of permits issued for new and
replacement OWTS and which Tier the permit is issued.
3.4 All local agencies permitting OWTS shall retain permanent records of their
permitting actions and will make those records available within 10 working days
upon written request for review by a Regional Water Board. The records for
each permit shall reference the Tier under which the permit was issued.
3.5 A local agency shall notify the owner of a public well or water intake and the
California Department of Public Health as soon as practicable, but not later
than 72 hours, upon its discovery of a failing OWTS as described in sections
11.1 and 11.2 within the setbacks described in sections 7.5.6 through 7.5.10.
3.6 A local agency may implement this Policy, or a portion thereof, using its local
authority to enforce the policy, as authorized by an approval from the State
Water Board or by the appropriate Regional Water Board.
3.7 Nothing in the Policy shall preclude a local agency from adopting or retaining
standards for OWTS in an approved Local Agency Management Program that
are more protective of the public health or the environment than are contained
in this Policy.
3.8 If at any time a local agency wishes to withdraw its previously submitted and
approved Tier 2 Local Agency Management Program, it may do so upon 60
days written notice. The notice of withdrawal shall specify the reason for
withdrawing its Tier 2 program, the effective date for cessation of the program
and resumption of permitting of OWTS only under Tiers 1, 3, and 4.
4.0 Regional Water Board Functions and Duties
4.1 The Regional Water Boards have the principal responsibility for overseeing the
implementation of this Policy.
4.2 Regional Water Boards shall incorporate the requirements established in this
Policy by amending their Basin Plans within 12 months of the effective date of
this Policy, pursuant to Water Code Section 13291(e). The Regional Water
14
Responsibilities and Duties
Boards may also consider whether it is necessary and appropriate to retain or
adopt any more protective standards. To the extent that a Regional Water
Board determines that it is necessary and appropriate to retain or adopt any
more protective standards, it shall reconcile those region -specific standards with
this Policy to the extent feasible, and shall provide a detailed basis for its
determination that each of the more protective standards is necessary and
appropriate.
4.2.1 Notwithstanding 4.2 above, the North Coast Regional Water Board will
continue to implement its existing Basin Plan requirements pertaining to
OWTS within the Russian River watershed until it adopts the Russian
River TMDL, at which time it will comply with section 4.2 for the Russian
River watershed.
4.3 The Regional Water Board designated in Attachment 3 shall review, and if
appropriate, approve a Local Agency Management Program submitted by the
local agency pursuant to Tier 2 in this Policy. Upon receipt of a proposed Local
Agency Management Program, the Regional Water Board designated in
Attachment 3 shall have 90 days to notify the local agency whether the submittal
contains all the elements of a Tier 2 program, but may request additional
information based on review of the proposed program. Approval must follow a
noticed hearing with opportunity for public comment. If a Local Agency
Management Program is disapproved, the Regional Water Board designated in
Attachment 3 shall provide a written explanation of the reasons for the
disapproval. A Regional Water Board may approve a Local Agency
Management Program while disapproving any proposed special provisions for
impaired water bodies contained in the Local Agency Management Program. If
no action is taken by the respective Regional Water Board within 12 months of
the submission date of a complete Local Agency Management Program, the
program shall be forwarded to the State Water Board for review and approval
pursuant to Section 5 of this Policy.
4.3.1 Where the local agency's jurisdiction lies within more than one Regional
Water Board, staff from the affected Regional Water Boards shall work
cooperatively to assure that water quality protection in each region is
adequately protected. If the Regional Water Board designated in
Attachment 3 approves the Local Agency Management Program over the
written objection of an affected Regional Water Board, that Regional
Water Board may submit the dispute to the State Water Board under
Section 5.3.
4.3.2 Within 30 days of receipt of a proposed Local Agency Management
Program, a Regional Water Board will forward a copy to and solicit
comments from the California Department of Public Health regarding a
Local Agency Management Program's proposed policies and procedures,
including notification to local water purveyors prior to OWTS permitting.
4.4 Once a Local Agency Management Program has been approved, any affected
Regional Water Board may require modifications or revoke authorization of a
local agency to implement a Tier 2 program, in accordance with the following:
15
Responsibilities and Duties
4.4.1 The Regional Water Board shall consult with any other Regional Water
Board(s) having jurisdiction over the local agency before providing the
notice described in section 4.4.2.
4.4.2 Written notice shall be provided to the local agency detailing the Regional
Water Board's action, the cause for such action, remedies to prevent the
action from continuing to completion, and appeal process and rights. The
local agency shall have 90 days from the date of the written notice to
respond with a corrective action plan to address the areas of non-
compliance, or to request the Regional Water Board to reconsider its
findings.
4.4.3 The Regional Water Board shall approve, approve conditionally, or deny a
corrective action plan within 90 days of receipt. The local agency will have
90 days to begin implementation of a corrective action plan from the date
of approval or 60 days to request reconsideration from the date of denial.
If the local agency fails to submit an acceptable corrective action plan,
fails to implement an approved corrective action plan, or request
reconsideration, the Regional Water Board may require modifications to
the Local Agency Management Program, or may revoke the local
agency's authorization to implement a Tier 2 program.
4.4.4 Requests for reconsideration by the local agency shall be decided by the
Regional Water Board within 90 days and the previously approved Local
Agency Management Program shall remain in effect while the
reconsideration is pending.
4.4.5 If the request for reconsideration is denied, the local agency may appeal
to the State Water Board and the previously approved Local Agency
Management Program shall remain in effect while the appeal is under
consideration. The State Water Board shall decide the appeal within 90
days. All decisions of the State Water Board are final.
4.5 The appropriate Regional Water Board shall accept and consider any requests
for modification or revocation of a Local Agency Management Program
submitted by any person. The Regional Water Board will notify the person
making the request and the local agency implementing the Local Agency
Management Program at issue by letter within 90 days whether it intends to
proceed with the modification or revocation process per Section 4.4 above, or is
dismissing the request. The Regional Water Board will post the request and its
response letter on its website.
4.6 A Regional Water Board may issue or deny waste discharge requirements or
waivers of waste discharge requirements for any new or replacement OWTS
within a jurisdiction of a local agency without an approved Local Agency
Management Program if that OWTS does not meet the minimum standards
contained in Tier 1.
4.7 The Regional Water Boards will implement any notifications and enforcement
requirements for OWTS determined to be in Tier 3 of this Policy.
16
Responsibilities and Duties
4.8 Regional Water Boards may adopt waste discharge requirements, or
conditional waivers of waste discharge requirements, that exempt individual
OWTS from requirements contained in this Policy.
5.0 State Water Board Functions and Duties
5.1 As the state agency charged with the development and adoption of this Policy,
the State Water Board shall periodically review, amend and/or update this
Policy as required.
5.2 The State Water Board may take any action assigned to the Regional Water
Boards in this Policy.
5.3 The State Water Board shall resolve disputes between Regional Water Boards
and local agencies as needed within 12 months of receiving such a request by
a Regional Water Board or local agency, and may take action on its own
motion in furtherance of this Policy. As part of this function, the State Water
Board shall review and, if appropriate, approve Local Agency Management
Programs in cases where the respective Regional Water Board has failed to
consider for approval a Local Agency Management Program. The State Water
Board shall approve Local Agency Management Programs at a regularly
noticed board hearing and shall provide for public participation, including notice
and opportunity for public comment. Once taken up by the State Water Board,
Local Agency Management Programs shall be approved or denied within 180
days.
5.4 A member of the public may request the State Water Board to resolve any
dispute regarding the Regional Water Board's approval of a Local Agency
Management Program if the member of the public timely raised the disputed
issue before the Regional Water Board. Such requests shall be submitted
within 30 days after the Regional Water Board's approval of the Local Agency
Management Program. The State Water Board shall notify the member of the
public, the local agency, and the Regional Water Board within 90 days whether
it intends to proceed with dispute resolution.
5.5 The State Water Board shall accept and consider any requests for modification
or revocation of a Local Agency Management Program submitted by any
person, where that person has previously submitted said request to the
Regional Water Board and has received notice from the Regional Water Board
of its dismissal of the request. The State Water Board will notify the person
making the request and the local agency implementing the Local Agency
Management Program at issue by letter within 90 days whether it intends to
proceed with the modification or revocation process per Section 4.4 above, or
is dismissing the request. The State Water Board will post the request and its
response letter on its website.
5.6 The State Water Board or its Executive Director, after approving any Impaired
Water Bodies [303 (d)] List, and for the purpose of implementing Tier 3 of this
Policy, shall update Attachment 2 to identify those water bodies where: (1) it is
likely that operating OWTS will subsequently be determined to be a contributing
17
Responsibilities and Duties
source of pathogens or nitrogen and therefore it is anticipated that OWTS
would receive a loading reduction, and (2) it is likely that new OWTS
installations discharging within 600 feet of the water body would contribute to
the impairment. This identification shall be based on information available at
the time of 303 (d) listing and may be further updated based on new
information. Updates to Attachment 2 will be processed as amendments to
this Policy.
5.7 The State Water Board will make available to local agencies funds from its
Clean Water State Revolving Fund loan program for mini -loan programs to be
operated by the local agencies for the making of low interest loans to assist
private property owners with complying with this Policy.
im
Tier 0 — Existing OWTS
Tier 0 — Existing OWTS
Existing OWTS that are properly functioning and do not meet the conditions of failing
systems or otherwise require corrective action (for example, to prevent groundwater
impairment) as specifically described in Tier 4, and are not determined to be
contributing to an impairment of surface water as specifically described in Tier 3, are
automatically included in Tier 0.
6.0 Coverage for Properly Operating Existing OWTS
6.1 Existing OWTS are automatically covered by Tier 0 and the herein included
waiver of waste discharge requirements if they meet the following
requirements:
6.1.1 have a projected flow of 10,000 gallons -per -day or less;
6.1.2 receive only domestic wastewater from residential or commercial
buildings, or high-strength wastewater from commercial food service
buildings that does not exceed 900 mg/L BOD and has a properly sized
and functioning oil/grease interceptor (a.k.a. grease trap);
6.1.3 continue to comply with any previously imposed permitting conditions;
6.1.4 do not require supplemental treatment under Tier 3;
6.1.5 do not require corrective action under Tier 4; and
6.1.6 do not consist of a cesspool as a means of wastewater disposal.
6.2 A Regional Water Board or local agency may deny coverage under this Policy
to any OWTS that is:
6.2.1 Not in compliance with Section 6.1;
6.2.2 Not able to adequately protect the water quality of the waters of the State,
as determined by the Regional Water Board after considering any input
from the local agency. A Regional Water Board may require the
submission of a report of waste discharge to receive Region specific
waste discharge requirements or waiver of waste discharge requirements
so as to be protective.
6.3 Existing OWTS currently under waste discharge requirements or individual
waiver of waste discharge requirements will remain under those orders until
notified in writing by the appropriate Regional Water Board that they are
covered under this Policy.
19
Tier 1 — Low Risk New or Replacement OWTS
Tier 1 — Low Risk New or Replacement OWTS
New or replacement OWTS meet low risk siting and design requirements as specified in
Tier 1, where there is not an approved Local Agency Management Program per Tier 2.
7.0 Minimum Site Evaluation and Siting Standards
7.1 A qualified professional shall perform all necessary soil and site evaluations for
all new OWTS and for existing OWTS where the treatment or dispersal system
will be replaced or expanded.
7.2 A site evaluation shall determine that adequate soil depth is present in the
dispersal area. Soil depth is measured vertically to the point where bedrock,
hardpan, impermeable soils, or saturated soils are encountered or an adequate
depth has been determined. Soil depth shall be determined through the use of
soil profile(s) in the dispersal area and the designated dispersal system
replacement area, as viewed in excavations exposing the soil profiles in
representative areas, unless the local agency has determined through historical
or regional information that a specific site soil profile evaluation is unwarranted.
7.3 A site evaluation shall determine whether the anticipated highest level of
groundwater within the dispersal field and its required minimum dispersal zone
is not less than prescribed in Table 2 by estimation using one or a combination
of the following methods:
7.3.1 Direct observation of the highest extent of soil mottling observed in the
examination of soil profiles, recognizing that soil mottling is not always an
indicator of the uppermost extent of high groundwater; or
7.3.2 Direct observation of groundwater levels during the anticipated period of
high groundwater. Methods for groundwater monitoring and
determinations shall be decided by the local agency; or
7.3.3 Other methods, such as historical records, acceptable to the local agency.
7.3.4 Where a conflict in the above methods of examination exists, the direct
observation method indicating the highest level shall govern.
7.4 Percolation test results in the effluent disposal area shall not be faster than one
minute per inch (1 MPI) or slower than one hundred twenty minutes per inch
(120 MPI). All percolation test rates shall be performed by presoaking of
percolation test holes and continuing the test until a stabilized rate is achieved.
7.5 Minimum horizontal setbacks from any OWTS treatment component and
dispersal systems shall be as follows:
7.5.1 5 feet from parcel property lines and structures;
7.5.2 100 feet from water wells and monitoring wells, unless regulatory or
legitimate data requirements necessitate that monitoring wells be located
closer;
20
Tier 1 — Low Risk New or Replacement OWTS
7.5.3 100 feet from any unstable land mass or any areas subject to earth slides
identified by a registered engineer or registered geologist; other setback
distance are allowed, if recommended by a geotechnical report prepared
by a qualified professional.
7.5.4 100 feet from springs and flowing surface water bodies where the edge of
that water body is the natural or levied bank for creeks and rivers, or may
be less where site conditions prevent migration of wastewater to the water
body;
7.5.5 200 feet from vernal pools, wetlands, lakes, ponds, or other surface water
bodies where the edge of that water body is the high water mark for lakes
and reservoirs, and the mean high tide line for tidally influenced water
bodies;
7.5.6 150 feet from a public water well where the depth of the effluent dispersal
system does not exceed 10 feet;
7.5.7 Where the effluent dispersal system is within 1,200 feet from a public
water systems' surface water intake point, within the catchment of the
drainage, and located such that it may impact water quality at the intake
point such as upstream of the intake point for flowing water bodies, the
dispersal system shall be no less than 400 feet from the high water mark
of the reservoir, lake or flowing water body.
7.5.8 Where the effluent dispersal system is located more than 1,200 feet but
less than 2,500 feet from a public water systems' surface water intake
point, within the catchment of the drainage, and located such that it may
impact water quality at the intake point such as upstream of the intake
point for flowing water bodies, the dispersal system shall be no less than
200 feet from the high water mark of the reservoir, lake or flowing water
body.
7.6 Prior to issuing a permit to install an OWTS the permitting agency shall
determine if the OWTS is within 1,200 feet of an intake point for a surface water
treatment plant for drinking water, is in the drainage catchment in which the
intake point is located, and located such that it may impact water quality at the
intake point such as being upstream of the intake point for a flowing water body.
If the OWTS is within 1,200 feet of an intake point for a surface water treatment
plant for drinking water, is in the drainage catchment in which the intake point is
located, and is located such that it may impact water quality at the intake point:
7.6.1 The permitting agency shall provide a copy of the permit application to the
owner of the water system of their proposal to install an OWTS within
1,200 feet of an intake point for a surface water treatment. If the owner of
the water system cannot be identified, then the permitting agency will
notify California Department of Public Health Drinking Water Program.
7.6.2 The permit application shall include a topographical plot plan for the parcel
showing the OWTS components, the property boundaries, proposed
structures, physical address, and name of property owner.
21
Tier 1 — Low Risk New or Replacement OWTS
7.6.3 The permit application shall provide the estimated wastewater flows,
intended use of proposed structure generating the wastewater, soil data,
and estimated depth to seasonally saturated soils.
7.6.4 The public water system owner shall have 15 days from receipt of the
permit application to provide recommendations and comments to the
permitting agency.
7.7 Natural ground slope in all areas used for effluent disposal shall not be greater
than 25 percent.
7.8 The average density for any subdivision of property made by Tentative Approval
pursuant to the Subdivision Map Act occurring after the effective date of this
Policy and implemented under Tier 1 shall not exceed the allowable density
values in Table 1 for a single-family dwelling unit, or its equivalent, for those
units that rely on OWTS.
Table 1: Allowable Average Densities per Subdivision under Tier 1.
Average Annual Rainfall
(in/yr)
Allowable Density
(acres/single family dwelling unit)
0-15
2.5
>15-20
2
>20 - 25
1.5
>25 - 35
1
>35 - 40
0.75
>40
0.5
8.0 Minimum OWTS Design and Construction Standards
8.1 OWTS Design Requirements
8.1.1 A qualified professional shall design all new OWTS and modifications to
existing OWTS where the treatment or dispersal system will be replaced
or expanded. A qualified professional employed by a local agency, while
acting in that capacity, may design, review, and approve a design for a
proposed OWTS, if authorized by the local agency.
8.1.2 OWTS shall be located, designed, and constructed in a manner to ensure
that effluent does not surface at any time, and that percolation of effluent
will not adversely affect beneficial uses of waters of the State.
8.1.3 The design of new and replacement OWTS shall be based on the
expected influent wastewater quality with a projected flow not to exceed
3,500 gallons per day, the peak wastewater flow rates for purposes of
sizing hydraulic components, the projected average daily flow for
purposes of sizing the dispersal system, the characteristics of the site, and
the required level of treatment for protection of water quality and public
health.
22
Tier 1 — Low Risk New or Replacement OWTS
8.1.4 All dispersal systems shall have at least twelve (12) inches of soil cover,
except for pressure distribution systems, which must have at least six (6)
inches of soil cover.
8.1.5 The minimum depth to the anticipated highest level of groundwater below
the bottom of the leaching trench, and the native soil depth immediately
below the leaching trench, shall not be less than prescribed in Table 2.
Table 2: Tier 1 Minimum Depths to Groundwater and Minimum Soil
Depth from the Bottom of the Dispersal System
Percolation Rate
Minimum Depth
Percolation Rate <_1 MPI
Only as authorized in a Tier 2 Local Agency
Management Program
1 MPI< Percolation Rate <_ 5
Twenty (20) feet
MPI
5 MPI< Percolation Rate <_ 30
Eight (8) feet
MPI
30 MPI< Percolation Rate <_
Five (5) feet
120 MPI
Percolation Rate > 120 MPI
Only as authorized in a Tier 2 Local Agency
Management Program
MPI = minutes per inch
8.1.6 Dispersal systems shall be a leachfield, designed using not more than 4
square -feet of infiltrative area per linear foot of trench as the infiltrative
surface, and with trench width no wider than 3 feet. Seepage pits and
other dispersal systems may only be authorized for repairs where siting
limitations require a variance. Maximum application rates shall be
determined from stabilized percolation rate as provided in Table 3, or from
soil texture and structure determination as provided in Table 4.
8.1.7 Dispersal systems shall not exceed a maximum depth of 10 feet as
measured from the ground surface to the bottom of the trench.
23
Tier 1 - Low Risk New or Replacement OWTS
Table 3: Application Rates as Determined from Stabilized Percolation Rate
Percolation
Rate
(minutes
per Inch)
Application
Rate
(gallons
per day per
square
foot)
Percolation
Rate
(minutes
per Inch)
Application
Rate
(gallons
per day per
square
foot)
Percolation
Rate
(minutes
per Inch)
Application
Rate
(gallons
per day per
square
foot)
<1
1
Requires
Local
Manage-
ment
Program
1.2
31
32
0.522
0.511
61
62
0.197
0.194
2
1.2
33
0.5
63
0.19
3
1.2
34
0.489
64
0.187
4
1.2
35
0.478
65
0.184
5
1.2
36
0.467
66
0.18
6
0.8
37
0.456
67
0.177
7
0.8
38
0.445
68
0.174
8
0.8
39
0.434
69
0.17
9
0.8
40
0.422
70
0.167
10
0.8
41
0.411
71
0.164
11
0.786
42
0.4
72
0.16
12
0.771
43
0.389
73
0.157
13
0.757
44
0.378
74
0.154
14
0.743
45
0.367
75
0.15
15
0.729
46
0.356
76
0.147
16
0.714
47
0.345
77
0.144
17
0.7
48
0.334
78
0.14
18
0.686
49
0.323
79
0.137
19
0.671
50
0.311
80
0.133
20
0.657
51
0.3
81
0.13
21
0.643
52
0.289
82
0.127
22
0.629
53
0.278
83
0.123
23
0.614
54
0.267
84
0.12
24
0.6
55
0.256
85
0.117
25
0.589
56
0.245
86
0.113
26
0.578
57
0.234
87
0.11
27
0.567
58
0.223
88
0.107
28
0.556
59
0.212
89
0.103
29
0.545
60
0.2
90
0.1
30
0.533
>90 - 120
0.1
24
Tier 1 — Low Risk New or Replacement OWTS
Table 4: Design Soil Application Rates
(Source: USEPA Onsite Wastewater Treatment Systems Manual, February 2002)
Soil Texture
(per the USDA soil classification
system)
Soil Structure Shape
Grade
Maximum Soil
Application
Rate(gallons per
day per square
foot)
Coarse Sand, Sand, Loamy Coarse
Sand, Loamy Sand
Single grain
Structureless
0.8
Fine Sand, Very Fine Sand, Loamy
Fine Sand, Loamy Very Fine Sand
Single grain
Structureless
0.4
Coarse Sandy Loam, Sandy Loam
Massive
Structureless
0.2
Platy
Weak
0.2
Moderate, Strong
Prohibited
Prismatic, Blocky,
Granular
Weak
0.4
Moderate, Strong
0.6
Fine Sandy Loam, very fine Sandy
Loam
Massive
Structureless
0.2
Platy
Weak, Moderate, Strong
Prohibited
Prismatic, Blocky,
Granular
Weak
0.2
Moderate, Strong
0.4
Loam
Massive
Structureless
0.2
Platy
Weak, Moderate, Strong
Prohibited
Prismatic, Blocky,
Granular
Weak
0.4
Moderate, Strong
0.6
Silt Loam
Massive
Structureless
Prohibited
Platy
Weak, Moderate, Strong
Prohibited
Prismatic, Blocky,
Granular
Weak
0.4
Moderate, Strong
0.6
Sandy Clay Loam, Clay Loam, Silty
Clay Loam
Massive
Structureless
Prohibited
Platy
Weak, Moderate, Strong
Prohibited
Prismatic, Blocky,
Granular
Weak
0.2
Moderate, Strong
0.4
Sandy Clay, Clay, or Silty Clay
Massive
Structureless
Prohibited
Platy
Weak, Moderate, Strong
Prohibited
Prismatic, Blocky,
Granular
Weak
Prohibited
Moderate, Strong
0.2
Soils listed as prohibited may be allowed under the authority of the Regional Water Board, or as allowed under an
approved Local Agency Management Program per Tier 2.
25
Tier 1 — Low Risk New or Replacement OWTS
8.1.8 All new dispersal systems shall have 100 percent replacement area that is
equivalent and separate, and available for future use.
8.1.9 No dispersal systems or replacement areas shall be covered by an
impermeable surface, such as paving, building foundation slabs, plastic
sheeting, or any other material that prevents oxygen transfer to the soil.
8. 1.10 Rock fragment content of native soil surrounding the dispersal system
shall not exceed 50 percent by volume for rock fragments sized as
cobbles or larger and shall be estimated using either the point -count or
line -intercept methods.
8.1.11 Increased allowance for IAPMO certified dispersal systems is not allowed
under Tier 1.
8.2 OWTS Construction and Installation
8.2.1 All new or replacement septic tanks and new or replacement oil/grease
interceptor tanks shall comply with the standards contained in Sections
K5(b), K5(c), K5(d), K5(e), K5(k), K5(m)(1), and K5(m)(3)(ii) of Appendix
K, of Part 5, Title 24 of the 2007 California Code of Regulations.
8.2.2 All new septic tanks shall comply with the following requirements:
8.2.2.1 Access openings shall have watertight risers, the tops of which shall be
set at most 6 inches below finished grade; and
8.2.2.2 Access openings at grade or above shall be locked or secured to
prevent unauthorized access.
8.2.3 New and replacement OWTS septic tanks shall be limited to those
approved by the International Association of Plumbing and Mechanical
Officials (IAPMO) or stamped and certified by a California registered civil
engineer as meeting the industry standards, and their installation shall be
according to the manufacturer's instructions.
8.2.4 New and replacement OWTS septic tanks shall be designed to prevent
solids in excess of three -sixteenths (3/16) of an inch in diameter from
passing to the dispersal system. Septic tanks that use a National
Sanitation Foundation/American National Standard Institute (NSF/ANSI)
Standard 46 certified septic tank filter at the final point of effluent
discharge from the OWTS and prior to the dispersal system shall be
deemed in compliance with this requirement.
26
Tier 1 — Low Risk New or Replacement OWTS
8.2.5 A Licensed General Engineering Contractor (Class A), General Building
Contractor (Class B), Sanitation System Contractor (Specialty Class C-
42), or Plumbing Contractor (Specialty Class C-36) shall install all new
OWTS and replacement OWTS in accordance with California Business
and Professions Code Sections 7056, 7057, and 7058 and Article 3,
Division 8, Title 16 of the California Code of Regulations. A property owner
may also install his/her own OWTS if the as -built diagram and the
installation are inspected and approved by the Regional Water Board or
local agency at a time when the OWTS is in an open condition (not
covered by soil and exposed for inspection).
27
Tier 2 — Local Agency OWTS Management Program
Tier 2 — Local Agency OWTS Management Program
Local agencies may submit management programs for approval, and upon approval
then manage the installation of new and replacement OWTS under that program. Local
Agency Management Programs approved under Tier 2 provide an alternate method
from Tier 1 programs to achieve the same policy purpose, which is to protect water
quality and public health. In order to address local conditions, Local Agency
Management Programs may include standards that differ from the Tier 1 requirements
for new and replacement OWTS contained in Sections 7 and 8. As examples, a Local
Agency Management Program may authorize different soil characteristics, usage of
seepage pits, and different densities for new developments. Once the Local Agency
Management Program is approved, new and replacement OWTS that are included
within the Local Agency Management Program may be approved by the Local Agency.
A Local Agency, at its discretion, may include Tier 1 standards within its Tier 2 Local
Agency Management Program for some or all of its jurisdiction. However, once a Local
Agency Management Program is approved, it shall supersede Tier 1 and all future
OWTS decisions will be governed by the Tier 2 Local Agency Management Program
until it is modified, withdrawn, or revoked.
9.0 Local Agency Management Program for Minimum OWTS Standards
The Local Agency Management Program for minimum OWTS Standards is a
management program where local agencies can establish minimum standards that are
differing requirements from those specified in Tier 1 (Section 7 and Section 8), including
the areas that do not meet those minimum standards and still achieve this Policy's
purpose. Local Agency Management Programs may include any one or combination of
the following to achieve this purpose:
• Differing system design requirements;
• Differing siting controls such as system density and setback requirements;
• Requirements for owners to enter monitoring and maintenance agreements;
and/or
• Creation of an onsite management district or zone.
9.1 Where different and/or additional requirements are needed to protect water quality
the local agency shall consider the following, as well as any other conditions
deemed appropriate, when developing Local Agency Management Program
requirements:
9.1.1 Degree of vulnerability to pollution from OWTS due to hydrogeological
conditions.
9.1.2 High Quality waters or other environmental conditions requiring enhanced
protection from the effects of OWTS.
9.1.3 Shallow soils requiring a dispersal system installation that is closer to
ground surface than is standard.
9.1.4 OWTS is located in area with high domestic well usage.
W
Tier 2 — Local Agency OWTS Management Program
9.1.5 Dispersal system is located in an area with fractured bedrock.
9.1.6 Dispersal system is located in an area with poorly drained soils.
9.1.7 Surface water is vulnerable to pollution from OWTS.
9.1.8 Surface water within the watershed is listed as impaired for nitrogen or
pathogens.
9.1.9 OWTS is located within an area of high OWTS density.
9.1.10 A parcel's size and its susceptibility to hydraulic mounding, organic or
nitrogen loading, and whether there is sufficient area for OWTS expansion in
case of failure.
9.1.11 Geographic areas that are known to have multiple, existing OWTS
predating any adopted standards of design and construction including
cesspools.
9.1.12 Geographic areas that are known to have multiple, existing OWTS located
within either the pertinent setbacks listed in Section 7.5 of this Policy, or a
setback that the local agencies finds is appropriate for that area.
9.2 The Local Agency Management Program shall detail the scope of its coverage,
such as the maximum authorized projected flows for OWTS, as well as a clear
delineation of those types of OWTS included within and to be permitted by the
program, and provide the local site evaluation, siting, design, and construction
requirements, and in addition each of the following:
9.2.1 Any local agency requirements for onsite wastewater system inspection,
monitoring, maintenance, and repairs, including procedures to ensure that
replacements or repairs to failing systems are done under permit from the
local governing jurisdiction.
9.2.2 Any special provisions applicable to OWTS within specified geographic
areas near specific impaired water bodies listed for pathogens or nitrogen.
The special provisions may be substantive and/or procedural, and may
include, as examples: consultation with the Regional Water Board prior to
issuing permits, supplemental treatment, development of a management
district or zone, special siting requirements, additional inspection and
monitoring.
9.2.3 Local Agency Management Program variances, for new installations and
repairs in substantial conformance, to the greatest extent practicable.
Variances are not allowed for the requirements stated in sections 9.4.1
through 9.4.9.
9.2.4 Any educational, training, certification, and/or licensing requirements that
will be required of OWTS service providers, site evaluators, designers,
installers, pumpers, maintenance contractors, and any other person
relating to OWTS activities.
9.2.5 Education and/or outreach program including informational materials to
inform OWTS owners about how to locate, operate, and maintain their
29
Tier 2 — Local Agency OWTS Management Program
OWTS as well as any Water Board order (e.g., Basin Plan prohibitions)
regarding OWTS restrictions within its jurisdiction. The education and/or
outreach program shall also include procedures to ensure that alternative
onsite system owners are provided an informational maintenance or
replacement document by the system designer or installer. This document
shall cite homeowner procedures to ensure maintenance, repair, or
replacement of critical items within 48 hours following failure. If volunteer
well monitoring programs are available within the local agency's
jurisdiction, the outreach program shall include information on how well
owners may participate.
9.2.6 An assessment of existing and proposed disposal locations for septage,
the volume of septage anticipated, and whether adequate capacity is
available.
9.2.7 Any consideration given to onsite maintenance districts or zones.
9.2.8 Any consideration given to the development and implementation of, or
coordination with, Regional Salt and Nutrient Management Plans.
9.2.9 Any consideration given to coordination with watershed management
groups.
9.2.10 Procedures for evaluating the proximity of sewer systems to new or
replacement OWTS installations.
9.2.11 Procedures for notifying the owner of a public water system prior to
issuing an installation or repair permit for an OWTS, if the OWTS is within
1,200 feet of an intake point for a surface water treatment plant for
drinking water, is in the drainage area catchment in which the intake point
is located, and is located such that it may impact water quality at the
intake point such as upstream of the intake point for a flowing water body,
or if the OWTS is within a horizontal sanitary setback from a public well.
9.2.12 Policies and procedures that will be followed when a proposed OWTS
dispersal area is within the horizontal sanitary setback of a public well or a
surface water intake point. These policies and procedures shall either
indicate that supplemental treatment as specified in 10.9 and 10.10 of this
policy are required for OWTS that are within a horizontal sanitary setback
of a public well or surface water intake point, or will establish alternate
siting and operational criteria for the proposed OWTS that would similarly
mitigate the potential adverse impact to the public water source.
9.2.13 Any plans for the phase-out or discontinuance of cesspool usage.
9.3 The minimum responsibilities of the local agency for management of the Local
Agency Management Program include:
9.3.1 Maintain records of the number, location, and description of permits
issued for OWTS where a variance is granted.
30
Tier 2 — Local Agency OWTS Management Program
9.3.2 Maintain a water quality assessment program to determine the general
operation status of OWTS and to evaluate the impact of OWTS
discharges, and assess the extent to which groundwater and local surface
water quality may be adversely impacted. The focus of the assessment
should be areas with characteristics listed under section 9.1. The
assessment program will include monitoring and analysis of water quality
data, review of complaints, variances, failures, and any information
resulting from inspections. The assessment may use existing water
quality data from other monitoring programs and/or establish the terms,
conditions, and timing for monitoring done by the local agency. At a
minimum this assessment will include monitoring data for nitrates and
pathogens, and may include data for other constituents which are needed
to adequately characterize the impacts of OWTS on water quality. Other
monitoring programs for which data may be used include but are not
limited to any of the following:
9.3.2.1. Random well samples from a domestic well sampling program.
9.3.2.2. Routine real estate transfer samples if those are performed and
reported.
9.3.2.3. Review of public system sampling reports done by the local agency
or another municipality responsible for the public system.
9.3.2.4. Water quality testing reports done at the time of new well
development if those are reported.
9.3.2.5. Beach water quality testing data performed as part of Health and
Safety Code Section 115885.
9.3.2.6. Receiving water sampling performed as a part of a NPDES permit.
9.3.2.7. Data contained in the California Water Quality Assessment
Database.
9.3.2.8. Groundwater sampling performed as part of Waste Discharge
Requirements.
9.3.2.9. Groundwater data collected as part of the Groundwater Ambient
Monitoring and Assessment Program and available in the
Geotracker Database.
9.3.3 Submit an annual report by February 1 to the applicable Regional Water
Board summarizing the status of items 9.3.1 through 9.3.2 above. Every
fifth year, submit an evaluation of the monitoring program and an
assessment of whether water quality is being impacted by OWTS,
identifying any changes in the Local Agency Management Program that
will be undertaken to address impacts from OWTS. The first report will
commence one year after approval of the local agency's Local Agency
Management Program. In addition to summarizing monitoring data
collected per 9.3.2 above, all groundwater monitoring data generated by
the local agency shall be submitted in EDF format for inclusion into
31
Tier 2 — Local Agency OWTS Management Program
Geotracker, and surface water monitoring shall be submitted to CEDEN in
a SWAMP comparable format.
9.4 The following are not allowed to be authorized in a Local Agency Management
Program:
9.4.1 Cesspools of any kind or size.
9.4.2 OWTS receiving a projected flow over 10,000 gallons per day.
9.4.3 OWTS that utilize any form of effluent disposal that discharges on or
above the post installation ground surface such as sprinklers, exposed
drip lines, free -surface wetlands, or a pond.
9.4.4 Slopes greater than 30 percent without a slope stability report approved by
a registered professional.
9.4.5 Decreased leaching area for IAPMO certified dispersal systems using a
multiplier less than 0.70.
9.4.6 OWTS utilizing supplemental treatment without requirements for periodic
monitoring or inspections.
9.4.7 OWTS dedicated to receiving significant amounts of wastes dumped from
RV holding tanks.
9.4.8 Separation of the bottom of dispersal system to groundwater less than two
(2) feet, except for seepage pits, which shall not be less than 10 feet.
9.4.9 Installation of new or replacement OWTS where public sewer is available.
The public sewer may be considered as not available when such public
sewer or any building or exterior drainage facility connected thereto is
located more than 200 feet from any proposed building or exterior
drainage facility on any lot or premises that abuts and is served by such
public sewer. This provision does not apply to replacement OWTS where
the connection fees and construction cost are greater than twice the total
cost of the replacement OWTS and the local agency determines that the
discharge from the OWTS will not affect groundwater or surface water to a
degree that makes it unfit for drinking or other uses.
9.4.10 Except as provided for in sections 9.4.11 and 9.4.12, new or replacement
OWTS with minimum horizontal setbacks less than any of the following:
9.4.10.1 150 feet from a public water well where the depth of the effluent
dispersal system does not exceed 10 feet in depth.
9.4.10.2 200 feet from a public water well where the depth of the effluent
dispersal system exceeds 10 feet in depth.
9.4.10.3 Where the effluent dispersal system is within 600 feet of a public
water well and exceeds 20 feet in depth the horizontal setback
required to achieve a two-year travel time for microbiological
contaminants shall be evaluated. A qualified professional shall
conduct this evaluation. However in no case shall the setback be
less than 200 feet.
32
Tier 2 — Local Agency OWTS Management Program
9.4.10.4 Where the effluent dispersal system is within 1,200 feet from a
public water systems' surface water intake point, within the
catchment of the drainage, and located such that it may impact
water quality at the intake point such as upstream of the intake
point for flowing water bodies, the dispersal system shall be no less
than 400 feet from the high water mark of the reservoir, lake or
flowing water body.
9.4.10.5 Where the effluent dispersal system is located more than 1,200 feet
but less than 2,500 feet from a public water systems' surface water
intake point, within the catchment area of the drainage, and located
such that it may impact water quality at the intake point such as
upstream of the intake point for flowing water bodies, the dispersal
system shall be no less than 200 feet from the high water mark of
the reservoir, lake or flowing water body.
9.4.11 For replacement OWTS that do not meet the above horizontal separation
requirements, the replacement OWTS shall meet the horizontal separation
to the greatest extent practicable. In such case, the replacement OWTS
shall utilize supplemental treatment and other mitigation measures, unless
the permitting authority finds that there is no indication that the previous
system is adversely affecting the public water source, and there is limited
potential that the replacement system could impact the water source
based on topography, soil depth, soil texture, and groundwater separation.
9.4.12 For new OWTS, installed on parcels of record existing at the time of the
effective date of this Policy, that cannot meet the above horizontal
separation requirements, the OWTS shall meet the horizontal separation
to the greatest extent practicable and shall utilize supplemental treatment
for pathogens as specified in section 10.8 and any other mitigation
measures prescribed by the permitting authority.
9.5 A Local Agency Management Program for OWTS must include adequate detail,
including technical information to support how all the criteria in their program
work together to protect water quality and public health.
9.6 A Regional Water Board reviewing a Local Agency Management Program shall
consider, among other things, the past performance of the local program to
adequately protect water quality, and where this has been achieved with criteria
differing from Tier 1, shall not unnecessarily require modifications to the
program for purposes of uniformity, as long as the Local Agency Management
Program meets the requirements of Tier 2.
33
Tier 3 — Impaired Areas
Tier 3 — Advanced Protection Management Programs for Impaired
Areas
Existing, new, and replacement OWTS that are near impaired water bodies may be
addressed by a TMDL and its implementation program, or special provisions contained
in a Local Agency Management Program. If there is no TMDL or special provisions,
new or replacement OWTS within 600 feet of impaired water bodies listed in Attachment
2 must meet the applicable specific requirements of Tier 3.
10.0 Advanced Protection Management Program
An Advanced Protection Management Program is the minimum required
management program for all OWTS located near a water body that has been listed
as impaired due to nitrogen or pathogen indicators pursuant to Section 303(d) of the
Clean Water Act. Local agencies are authorized to implement Advanced Protection
Management Programs in conjunction with an approved Local Agency Management
Program or, if there is no approved Local Agency Management Program, Tier 1.
Local agencies are encouraged to collaborate with the Regional Water Boards by
sharing any information pertaining to the impairment, provide advice on potential
remedies, and regulate OWTS to the extent that their authority allows for the
improvement of the impairment.
10.1 The geographic area for each water body's Advanced Protection Management
Program is defined by the applicable TMDL, if one has been approved. If there
is not an approved TMDL, it is defined by an approved Local Agency
Management Program, if it contains special provisions for that water body. If it
is not defined in an approved TMDL or Local Agency Management Program, it
shall be 600 linear feet [in the horizontal (map) direction] of a water body listed
in Attachment 2 where the edge of that water body is the natural or levied bank
for creeks and rivers, the high water mark for lakes and reservoirs, and the
mean high tide line for tidally influenced water bodies, as appropriate. OWTS
near impaired water bodies that are not listed on Attachment 2, and do not
have a TMDL and are not covered by a Local Agency Management Program
with special provisions, are not addressed by Tier 3.
10.2 The requirements of an Advanced Protection Management Program will be in
accordance with a TMDL implementation plan, if one has been adopted to
address the impairment. An adopted TMDL implementation plan supersedes
all other requirements in Tier 3. All TMDL implementation plans adopted after
the effective date of this Policy that contain load allocations for OWTS shall
include a schedule that requires compliance with the load allocations as soon
as practicable, given the watershed -specific circumstances. The schedule shall
require that OWTS implementation actions for OWTS installed prior to the
TMDL implementation plan's effective date shall commence within 3 years after
the TMDL implementation plan's effective date, and that OWTS implementation
actions for OWTS installed after the TMDL implementation plan's effective date
shall commence immediately. The TMDL implementation plan may use some
or all of the Tier 3 requirements and shall establish the applicable area of
34
Tier 3 — Impaired Areas
implementation for OWTS requirements within the watershed. For those
impaired water bodies that do have an adopted TMDL addressing the
impairment, but the TMDL does not assign a load allocation to OWTS, no
further action is required unless the TMDL is modified at some point in the
future to include actions for OWTS. Existing, new, and replacement OWTS that
are near impaired water bodies and are covered by a Basin Plan prohibition
must also comply with the terms of the prohibition, as provided in Section 2.1.
10.3 In the absence of an adopted TMDL implementation plan, the requirements of
an Advanced Protection Management Program will consist of any special
provisions for the water body if any such provisions have been approved as
part of a Local Agency Management Program.
10.4 The Regional Water Boards shall adopt TMDLs for impaired water bodies
identified in Attachment 2, in accordance with the specified dates.
10.4.1 If a Regional Water Board does not complete a TMDL within two years of
the time period specified in Attachment 2, coverage under this Policy's
waiver of waste discharge requirements shall expire for any OWTS that
has any part of its dispersal system discharging within the geographic
area of an Advanced Protection Management Program. The Regional
Water Board shall issue waste discharge requirements, general waste
discharge requirements, waivers of waste discharge requirements, or
require corrective action for such OWTS. The Regional Water Board will
consider the following when establishing the waste discharge
requirements, general waste discharge requirements, waivers of waste
discharge requirements, or requirement for corrective action:
10.4.1.1 Whether supplemental treatment should be required.
10.4.1.2 Whether routine inspection of the OWTS should be required.
10.4.1.3 Whether monitoring of surface and groundwater should be
performed.
10.4.1.4 The collection of a fee for those OWTS covered by the order.
10.4.1.5 Whether owners of previously -constructed OWTS should file a
report by a qualified professional in accordance with section 10.5.
10.4.1.6 Whether owners of new or replacement OWTS should file a report
of waste discharge with additional supporting technical information
as required by the Regional Water Board.
10.5 If the Regional Water Board requires owners of OWTS to submit a qualified
professional's report pursuant to Section 10.4.1.5, the report shall include a
determination of whether the OWTS is functioning properly and as designed or
requires corrective actions per Tier 4, and regardless of its state of function,
whether it is contributing to impairment of the water body.
10.5.1 The qualified professional's report may also include, but is not limited to:
35
Tier 3 — Impaired Areas
10.5.1.1
A general description of system components, their physical layout,
and horizontal setback distances from property lines, buildings, wells,
and surface waters.
10.5.1.2
A description of the type of wastewater discharged to the OWTS
such as domestic, commercial, or industrial and classification of it as
domestic wastewater or high-strength waste.
10.5.1.3
A determination of the systems design flow and the volume of
wastewater discharged daily derived from water use, either estimated
or actual if metered.
10.5.1.4
A description of the septic tank, including age, size, material of
construction, internal and external condition, water level, scum layer
thickness, depth of solids, and the results of a one-hour hydrostatic
test.
10.5.1.5
A description of the distribution box, dosing siphon, or distribution
pump, and if flow is being equally distributed throughout the dispersal
system, as well as any evidence of solids carryover, clear water
infiltration, or evidence of system backup.
10.5.1.6
A description of the dispersal system including signs of hydraulic
failure, condition of surface vegetation over the dispersal system,
level of ponding above the infiltrative surface within the dispersal
system, other possible sources of hydraulic loading to the dispersal
area, and depth of the seasonally high groundwater level.
10.5.1.7
A determination of whether the OWTS is discharging to the ground's
surface.
10.5.1.8
For a water body listed as an impaired water body for pathogens, a
determination of the OWTS dispersal system's separation from its
deepest most infiltrative surface to the highest seasonal groundwater
level or fractured bedrock.
10.5.1.9
For a water body listed as an impaired water body for nitrogen, a
determination of whether the groundwater under the dispersal field is
reaching the water body, and a description of the method used to
make the determination.
10.6 For new,
replacement, and existing OWTS in an Advanced Protection
Management Program, the following are not covered by this Policy's waiver but
may be authorized
by a separate Regional Water Board order:
10.6.1 Cesspools of any kind or size.
10.6.2 OWTS receiving a projected flow over 10,000 gallons per day.
10.6.3 OWTS that utilize any form of effluent disposal on or above the ground
surface.
10.6.4 Slopes greater than 30 percent without a slope stability report approved by
a registered professional.
36
Tier 3 — Impaired Areas
10.6.5 Decreased leaching area for IAPMO certified dispersal systems using a
multiplier less than 0.70.
10.6.6 OWTS utilizing supplemental treatment without requirements for periodic
monitoring or inspections.
10.6.7 OWTS dedicated to receiving significant amounts of wastes dumped from
RV holding tanks.
10.6.8 Separation of the bottom of dispersal system to groundwater less than two
(2) feet, except for seepage pits, which shall not be less than 10 feet.
10.6.9 Minimum horizontal setbacks less than any of the following:
10.6.9.1 150 feet from a public water well where the depth of the effluent
dispersal system does not exceed 10 feet in depth;
10.6.9.2 200 feet from a public water well where the depth of the effluent
dispersal system exceeds 10 feet in depth:
10.6.9.3 Where the effluent dispersal system is within 600 feet of a public
water well and exceeds 20 feet in depth the horizontal setback
required to achieve a two-year travel time for microbiological
contaminants shall be evaluated. A qualified professional shall
conduct this evaluation. However in no case shall the setback be
less than 200 feet.
10.6.9.4 Where the effluent dispersal system is within 1,200 feet from a
public water systems' surface water intake point, within the
catchment of the drainage, and located such that it may impact
water quality at the intake point such as upstream of the intake
point for flowing water bodies, the dispersal system shall be no less
than 400 feet from the high water mark of the reservoir, lake or
flowing water body.
10.6.9.5 Where the effluent dispersal system is located more than 1,200 feet
but less than 2,500 feet from a public water systems' surface water
intake point, within the catchment of the drainage, and located such
that it may impact water quality at the intake point such as
upstream of the intake point for flowing water bodies, the dispersal
system shall be no less than 200 feet from the high water mark of
the reservoir, lake or flowing water body.
10.6.9.6 For replacement OWTS that do not meet the above horizontal
separation requirements, the replacement OWTS shall meet the
horizontal separation to the greatest extent practicable. In such
case, the replacement OWTS shall utilize supplemental treatment
and other mitigation measures.
10.6.9.7 For new OWTS, installed on parcels of record existing at the time of
the effective date of this Policy, that cannot meet the above
horizontal separation requirements, the OWTS shall meet the
horizontal separation to the greatest extent practicable and shall
37
Tier 3 — Impaired Areas
utilize supplemental treatment for pathogens as specified in section
10.10 and any other mitigation measures as prescribed by the
permitting authority.
10.7 The requirements contained in Section 10 shall not apply to owners of OWTS
that are constructed and operating, or permitted, on or prior to the date that the
nearby water body is added to Attachment 2 who commit by way of a legally
binding document to connect to a centralized wastewater collection and
treatment system regulated through WDRs as specified within the following
timeframes:
10.7.1 The owner must sign the document within forty-eight months of the date
that the nearby water body is initially listed on Attachment 2.
10.7.2 The specified date for the connection to the centralized community
wastewater collection and treatment system shall not extend beyond nine
years following the date that the nearby water body is added to
Attachment 2.
10.8 In the absence of an adopted TMDL implementation plan or Local Agency
Management Program containing special provisions for the water body, all new
or replacement OWTS permitted after the date that the water body is initially
listed in Attachment 2 that have any discharge within the geographic area of an
Advanced Protection Management Program shall meet the following
requirements:
10.8.1 Utilize supplemental treatment and meet performance requirements in
10.9 if impaired for nitrogen and 10.10 if impaired for pathogens,
10.8.2 Comply with the setback requirements of Section 7.5.1 to 7.5.5, and
10.8.3 Comply with any applicable Local Agency Management Program
requirements.
10.9 Supplemental treatment requirements for nitrogen
10.9.1 Effluent from the supplemental treatment components designed to
reduce nitrogen shall be certified by NSF, or other approved third party
tester, to meet a 50 percent reduction in total nitrogen when comparing
the 30 -day average influent to the 30 -day average effluent.
10.9.2 Where a drip -line dispersal system is used to enhance vegetative
nitrogen uptake, the dispersal system shall have at least six (6) inches
of soil cover.
W
Tier 3 — Impaired Areas
10.10 Supplemental treatment requirements for pathogens
10.10.1 Supplemental treatment components designed to perform
disinfection shall provide sufficient pretreatment of the wastewater so that
effluent from the supplemental treatment components does not exceed a
30 -day average TSS of 30 mg/L and shall further achieve an effluent
fecal coliform bacteria concentration less than or equal to 200 Most
Probable Number (MPN) per 100 milliliters.
10.10.2 The minimum soil depth and the minimum depth to the anticipated
highest level of groundwater below the bottom of the dispersal system
shall not be less than three (3) feet. All dispersal systems shall have at
least twelve (12) inches of soil cover.
10.11 OWTS in an Advanced Protection Management Program with supplemental
treatment shall be designed to meet the applicable performance requirements
above and shall be stamped or approved by a Qualified Professional.
10.12 Prior to the installation of any proprietary treatment OWTS in an Advanced
Protection Management Program, all such treatment components shall be
tested by an independent third party testing laboratory.
10.13 The ongoing monitoring of OWTS in an Advanced Protection Management
Program with supplemental treatment components designed to meet the
performance requirements in Sections 10.9 and 10.10 shall be monitored in
accordance with the operation and maintenance manual for the OWTS or
more frequently as required by the local agency or Regional Water Board.
10.14 OWTS in an Advanced Protection Management Program with supplemental
treatment components shall be equipped with a visual or audible alarm as
well as a telemetric alarm that alerts the owner and service provider in the
event of system malfunction. Where telemetry is not possible, the owner or
owner's agent shall inspect the system at least monthly while the system is in
use as directed and instructed by a service provider and notify the service
provider not less than quarterly of the observed operating parameters of the
OWTS.
10.15 OWTS in an Advanced Protection Management Program designed to meet
the disinfection requirements in Section 10.10 shall be inspected for proper
operation quarterly while the system is in use by a service provider unless a
telemetric monitoring system is capable of continuously assessing the
operation of the disinfection system. Testing of the wastewater flowing from
supplemental treatment components that perform disinfection shall be
sampled at a point in the system after the treatment components and prior to
the dispersal system and shall be conducted quarterly based on analysis of
total coliform with a minimum detection limit of 2.2 MPN. All effluent samples
must include the geographic coordinates of the sample's location. Effluent
samples shall be taken by a service provider and analyzed by a California
Department of Public Health certified laboratory.
39
Tier 3 — Impaired Areas
10.16 The minimum responsibilities of a local agency administering an Advanced
Protection Management Program include those prescribed for the Local
Agency Management Programs in Section 9.3 of this policy, as well as
monitoring owner compliance with Sections 10.13, 10.14,and 10.15.
W
Tier 4 — OWTS Requiring Corrective Action
Tier 4 — OWTS Requiring Corrective Action
OWTS that require corrective action or are either presently failing or fail at any time
while this Policy is in effect are automatically included in Tier 4 and must follow the
requirements as specified. OWTS included in Tier 4 must continue to meet applicable
requirements of Tier 0, 1, 2 or 3 pending completion of corrective action.
11.0 Corrective Action for OWTS
11.1 Any OWTS that has pooling effluent, discharges wastewater to the surface, or
has wastewater backed up into plumbing fixtures, because its dispersal
system is no longer adequately percolating the wastewater is deemed to be
failing, no longer meeting its primary purpose to protect public health, and
requires major repair, and as such the dispersal system must be replaced,
repaired, or modified so as to return to proper function and comply with Tier 1,
2, or 3 as appropriate.
11.2 Any OWTS septic tank failure, such as a baffle failure or tank structural
integrity failure such that either wastewater is exfiltrating or groundwater is
infiltrating is deemed to be failing, no longer meeting its primary purpose to
protect public health, and requires major repair, and as such shall require the
septic tank to be brought into compliance with the requirements of Section 8
in Tier 1 or a Local Agency Management Program per Tier 2.
11.3 Any OWTS that has a failure of one of its components other than those
covered by 11.1 and 11.2 above, such as a distribution box or broken piping
connection, shall have that component repaired so as to return the OWTS to
a proper functioning condition and return to Tier 0, 1, 2, or 3.
11.4 Any OWTS that has affected, or will affect, groundwater or surface water to a
degree that makes it unfit for drinking or other uses, or is causing a human
health or other public nuisance condition shall be modified or upgraded so as
to abate its impact.
11.5 If the owner of the OWTS is not able to comply with corrective action
requirements of this section, the Regional Water Board may authorize repairs
that are in substantial conformance, to the greatest extent practicable, with
Tiers 1 or 3, or may require the owner of the OWTS to submit a report of
waste discharge for evaluation on a case-by-case basis. Regional Water
Board response to such reports of waste discharge may include, but is not
limited to, enrollment in general waste discharge requirements, issuance of
individual waste discharge requirements, or issuance of waiver of waste
discharge requirements. A local agency may authorize repairs that are in
substantial conformance, to the greatest extent practicable, with Tier 2 in
accordance with section 9.2.3 if there is an approved Local Agency
Management Program, or with an existing program if a Local Agency
Management Program has not been approved and it is less than 5 years from
the effective date of the Policy.
41
Tier 4 — OWTS Requiring Corrective Action
11.6 Owners of OWTS will address any corrective action requirement of Tier 4 as
soon as is reasonably possible, and must comply with the time schedule of
any corrective action notice received from a local agency or Regional Water
Board, to retain coverage under this Policy.
11.7 Failure to meet the requirements of Tier 4 constitute a failure to meet the
conditions of the waiver of waste discharge requirements contained in this
Policy, and is subject to further enforcement action.
:,
Waiver — Effective Date — Financial Assistance
Conditional Waiver of Waste Discharge Requirements
12.0 In accordance with Water Code section 13269, the State Water Board hereby
waives the requirements to submit a report of waste discharge, obtain waste
discharge requirements, and pay fees for discharges from OWTS covered by this
Policy. Owners of OWTS covered by this Policy shall comply with the following
conditions:
12.0.1 The OWTS shall function as designed with no surfacing effluent.
12.0.2 The OWTS shall not utilize a dispersal system that is in soil saturated with
groundwater.
12.0.3 The OWTS shall not be operated while inundated by a storm or flood
event.
12.0.4 The OWTS shall not cause or contribute to a condition of nuisance or
pollution.
12.0.5 The OWTS shall comply with all applicable local agency codes,
ordinances, and requirements.
12.0.6 The OWTS shall comply with and meet any applicable TMDL
implementation requirements, special provisions for impaired water
bodies, or supplemental treatment requirements imposed by Tier 3.
12.0.7 The OWTS shall comply with any corrective action requirements of Tier 4.
12.1 This waiver may be revoked by the State Water Board or the applicable Regional
Water Board for any discharge from an OWTS, or from a category of OWTS.
Effective Date
13.0 This Policy becomes effective six months after its approval by the Office of
Administrative Law, and all deadlines and compliance dates stated herein start at
such time.
43
Waiver — Effective Date — Financial Assistance
Financial Assistance
14.0 Local Agencies may apply to the State Water Board for funds from the Clean
Water State Revolving Fund for use in mini -loan programs that provide low
interest loan assistance to private property owners with costs associated with
complying with this Policy.
14.1 Loan interest rates for loans to local agencies will be set by the State
Water Board using its policies, procedures, and strategies for
implementing the Clean Water State Revolving Fund program, but will
typically be one-half of the States most recent General Obligation bond
sale. Historically interest rates have ranged between 2.0 and 3.0 percent.
14.2 Local agencies may add additional interest points to their loans made to
private entities to cover their costs of administering the mini -loan program.
14.3 Local agencies may submit their suggested loan eligibility criteria for the
min -loan program they wish to establish to the State Water Board for
approval, but should consider the legislative intent stated in Water Code
Section 13291.5 is that assistance is encouraged for private property
owners whose cost of complying with the requirements of this policy
exceeds one-half of one percent of the current assessed value of the
property on which the OWTS is located.
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Attachment 3
Regional Water Boards, upon mutual agreement, may designate one Regional Water
Board to regulate a person or entity that is under the jurisdiction of both (Water Code
Section 13228). The following table identifies the designated Regional Water Board for
all counties within the State for purposes of reviewing and, if appropriate, approving new
Local Agency Management Plans.
Table 7. Regional Water Board designations by County.
County
Regions with
Jurisdiction
Designated
Region
Alameda
2,5
2
Alpine
5,6
6
Amador
5
5
Butte
5
5
Calaveras
5
5
Colusa
5
5
Contra
Costa
2,5
2
Del Norte
1
1
EI Dorado
5,6
5
Fresno
5
5
Glenn
5,1
5
Humboldt
1
1
Imperial
7
7
I nyo
6
6
Kern
3,4,5,6
5
Kings
5
5
Lake
5,1
5
Lassen
5,6
6
Los Angeles
4,6
4
Madera
5
5
Marin
2,1
2
Mariposa
5
5
Mendocino
1
1
Merced
5
5
Modoc
1,5,6
5
Mono
6
6
Monterey
3
3
Napa
2,5
2
Nevada
5,6
5
Orange
8,9
8
50
County
Regions with
Jurisdiction
Designated
Region
Placer
5,6
5
Plumas
5
5
Riverside
7,8,9
7
Sacramento
5
5
San Benito
3,5
3
San
Bernardino
6,7,8
6
San Diego
9,7
9
San
Francisco
2
2
San Joaquin
5
5
San Luis
Obispo
3,5
3
San Mateo
2,3
2
Santa
Barbara
3
3
Santa Clara
2,3
2
Santa Cruz
3
3
Shasta
5
5
Sierra
5,6
5
Siskiyou
1,5
1
Solano
2,5
5
Sonoma
1,2
1
Stanislaus
5
5
Sutter
5
5
Tehama
5
5
Trinity
1
1
Tulare
5
5
Tuolumne
5
5
Ventura
4,3
4
Yolo
5
5
Yuba
5
5
ENVIRONMENTAL HEALTH
Environmental Protection Branch
5050 Commerce Drive, Baldwin Park, CA 91706
Telephone: (626) 430-5270 • Website: http://www.publichealth.lacounty.gov/eh
LOCAL AGENCY MANAGEMENT PROGRAM
FOR
ONSITE WASTEWATER TREATMENT SYSTEMS
LOS ANGELES COUNTY, CALIFORNIA
Submitted to:
California Regional Water Quality Control Board
Los Angeles Region
County of Los Angeles
Department of Public Health, Environmental Health
MAY 17, 2018
ENVIRONMENTAL HEALTH
Environmental Protection Branch
5050 Commerce Drive, Baldwin Park, CA 91706
Telephone: (626) 430-5270 • Website: http://www.publichealth.lacounty.gov/eh
THIS PAGE LEFT INTENTIONALLY BLANK
Acknowledgments
This document was developed under the direction of the County of Los Angeles, Department
of Public Health, Environmental Health. Preparation of this plan was achieved through the
efforts and contributions of the following individuals:
Gregory Sena, Department of Public Works
Scott Abbott, REHS, MPA, Department of Public Health
Michelle Tsiebos, REHS, MPA, DPA, Department of Public Health
TJ Moon, Department of Public Works
Ajay M. Malik, PE, Sanitation Districts of Los Angeles County
Kevin Bryan, PG, CEG, Leighton Consulting Inc.
Julie C. Harriman, PE, Leighton Consulting Inc.
Ronald Schnabel, PG, CHG, Dudek
Peter Quinlan, PG, Dudek
Eric Wu, PhD, PE, Los Angeles Regional Water Quality Control Board \[consultation\]
Don Tsai, PhD, Los Angeles Regional Water Quality Control Board \[consultation\]
Peter Raftery, PG, CHG, Los Angeles Regional Water Quality Control Board
\[consultation\]
Jehiel Cass, PE, Lahontan Regional Water Quality Control Board \[consultation\]
Mike Coony, PE, Lahontan Regional Water Quality Control Board \[consultation\]
During the preparation of this document, the Department of Public Health, Environmental
Health reached out to the following local municipal, industry and environmental groups for
comments regarding the State Water Resources Control Board’s Water Quality Control Policy
for Siting, Design, Operation andMaintenance of Onsite Wastewater Treatment Systems:
Association of Rural Town Councils; Barton Slutske Consulting; BioSolutions Inc.; City of Los
Angeles; City of Malibu; Earth Resources Inc.; EnviroSepTec Inc.; Erler&Kalinowski Inc.;
GeoConcepts Inc.; Heal the Bay; Miller Geosciences Inc.; Natural Resources Defense
Council; Resource Conservation Districts of the Santa Monica Mountains; Surfrider
Foundation; Topanga Underground; TreePeople; WRA Engineering Inc.; and Young
Environmental Services LLC.
ii
TABLE OF CONTENTS
SECTIONPAGE
ACKNOWLEDGMENTS.......................................................................................................II
LIST OF ACRONYMS.........................................................................................................VI
EXECUTIVE SUMMARY......................................................................................................1
1.0 INTRODUCTION AND BACKGROUND.......................................................................6
1.1 Introduction.....................................................................................................6
1.1.1 Authority to Operate Program..............................................................7
1.1.2 Definitions...........................................................................................8
1.2 Geographical Area........................................................................................17
1.3 RegulationofOnsiteWastewaterTreatmentSystems (OWTS)....................18
1.4 Los Angeles CountyCodes Applicable to OWTS..........................................18
1.5 Los Angeles CountyRequirements and Procedures for OWTS and NOWTS
(Professional Guide)......................................................................................22
1.6 OrganizationofthisLAMP............................................................................24
2.0 ENVIRONMENTALCONDITIONS,OWTSUSAGEANDWATERQUALITY
MANAGEMENTINLOS ANGELESCOUNTY........................................................26
2.1 SurfaceWaterHydrology..............................................................................26
2.1.1 Topography.......................................................................................26
2.1.2 Geology and Soils.............................................................................26
2.1.3 Climate..............................................................................................28
2.1.4 Coastal Plain and Mountain Areas....................................................28
2.1.5 Desert Areas.....................................................................................29
2.1.6 Watersheds.......................................................................................29
2.1.6.1 Santa Clara River..................................................................31
2.1.6.2 Los Angeles River.................................................................31
2.1.6.3 San Gabriel River..................................................................32
2.1.6.4 Antelope-Fremont Valleys.....................................................34
2.1.6.5 Santa Monica Bay.................................................................35
2.1.6.6 Santa Ana..............................................................................36
2.1.6.7 Mojave...................................................................................37
2.1.6.8 Calleguas..............................................................................38
2.1.6.9 Middle Kern-Upper Tehachapi-Grapevine.............................39
2.2 Groundwater.................................................................................................39
2.2.1 Antelope Valley (6-44).......................................................................40
2.2.2 Acton Valley (4-05)............................................................................41
2.2.3 Santa Clara River Valley East (4-04.07)............................................42
2.2.4 San Fernando Valley (14-12)............................................................43
2.2.5 Raymond (4-23)................................................................................43
iii
2.2.6 San GabrielValley (4-13)..................................................................44
2.2.7 Coastal Plain ofLos Angeles Santa Monica (4-11.01)......................45
2.2.8Coastal Plain of Los Angeles West-Coast (4-11.03)..........................45
2.2.9 Coastal Plainof Los Angeles Central (4-11.04).................................46
2.3 Geologic Factors, OWTS Suitability and Soils..............................................49
2.4 OWTS Usage Estimates...............................................................................55
2.5 Water Quality Management Measures.........................................................59
3.0 OWTS SITING, DESIGN AND CONSTRUCTION REQUIREMENTS..........................68
3.1 Site Evaluations for OWTS...........................................................................68
3.2 Wastewater Flows for OWTS Design...........................................................75
3.3 Materials and Equipment..............................................................................76
3.4 Conventional OWTS Requirements..............................................................77
3.5 NOWTS Requirements.................................................................................86
3.6 Types of NOWTS Permitted.........................................................................91
4.0 SPECIAL OWTS MANAGEMENT ISSUES..................................................................93
4.1 OWTS and NOWTS Inspection, Monitoring, Maintenance and Repair.........93
4.2 OWTS Near Impaired Water Bodies.............................................................95
4.3 Variances and Exceptions............................................................................97
4.4 Professional, Contractor and Maintenance Provider Qualifications............101
4.5 Education and Outreach.............................................................................102
4.6 Septage Management................................................................................103
4.7 Onsite Maintenance Districts......................................................................104
4.8 Regional Salt and Nutrient Management Plans..........................................104
4.9 Watershed Management Coordination.......................................................105
4.10 Evaluating Proximity to Public Sewers........................................................106
4.11 OWTS Notification to Public Water System Owner(s)................................106
4.12 Policies and Procedures when a Proposed OWTS Dispersal Area is within the
Horizontal Sanitary Setback of a Public Well..............................................107
4.13 Phase-Out of Cesspool Usage...................................................................108
5.0 PROHIBITIONS........................................................................................................109
6.0 PROGRAM ADMINISTRATION.................................................................................111
6.1 OWTS Permitting Records.........................................................................111
6.2 Staffing of Land Use Program....................................................................111
6.3 Water Quality Assessment Program...........................................................111
6.4 Reporting to RWQCBs...............................................................................114
7.0 REFERENCES..........................................................................................................116
iv
LIST OF ACCOMPANYING ATTACHMENTS
TablesPage
Table 1-1 Los Angeles County OWTS Codes Summary....................................................21
Table 2-1 South County Area (Los Angeles RWQCB Region 4), Estimated Existing
OWTS by Watershed..............................................................................................55
Table 2-2 North County Area (Lahontan RWQCB Region 6), Estimated Existing
OWTS by Watershed..............................................................................................56
Table 2-3 Water Bodies Impaired for Pathogens or Nitrogen that are Subject to Tier
3 in Los Angeles County.........................................................................................65
Table 2-4 Allowable Average Densities per Subdivision....................................................67
Table 3-1 Minimum Vertical Separation to Groundwater for Leach Field and Leach Bed
Dispersal Systems...................................................................................................71
Table 3-2 Minimum Vertical Separation to Groundwater with Percolation Rates for
OWTS, NOWTS and Seepage Pits.........................................................................73
Table 3-3 Estimated Waste/Sewage Flow Rates...............................................................75
Table 3-4 Minimum Horizontal Setback Distances.............................................................78
Table 3-5 Capacity of Septic Tanks....................................................................................80
Table 4-1 Summary of Los Angeles County Provisions for OWTS/NOWTS
Inspection, Monitoring, Maintenance and Repairs..................................................93
Table 4-2 Summary of TMDLwith OWTS Allotment for Impaired Water Body –
Malibu Creek...........................................................................................................97
Table 4-3 Qualifications for OWTS Practitioners..............................................................101
Table 4-4 Annual Septage Generation in Los Angeles County........................................104
FiguresPage
Figure 1-1 Los Angeles County Distribution of OWTS.......................................................19
Figure 1-2Los AngelesCounty Distribution of NOWTS ....................................................20
Figure 2-1 Los Angeles County Watersheds .....................................................................30
Figure 2-2 Los Angeles County GroundwaterBasins andSub-Basins .............................48
Figure 2-3 LosAngeles County Hydrologic Soils in Watersheds Map...............................54
Figure 2-4 Los Angeles County Average Annual Precipitation Map ..................................57
Figure 2-5 Los Angeles County Estimated Existing Development of OWTS .....................58
Figure 4-1 Los Angeles County Impaired Water Bodies..................................................100
Appendices
Appendix A –Supporting Rationale for Los Angeles County OWTS Siting and Design
Criteria
Appendix B –Cumulative Nitrate and Salt Loading from OWTS in Los Angeles County
v
LIST OF ACRONYMS
ANSIAmerican National Standards Institute
APMPAdvanced Protection Management Program
BODbiochemical oxygen demand
CBODcarbonaceous biochemical oxygen demand
CEDENCalifornia Environmental Data Exchange Network
CEGCertified Engineering Geologist
CHGCertified Hydrogeologist
CRWQCBCalifornia Regional Water Control Board
DPHDepartment of Public Health
DPWDepartment of Public Works
EDFElectronic deliverable format
EHEnvironmental Health
EPAEnvironmental Protection Agency
FOGFats, oil, grease
gpdgallons per day
HUChydrologic unit code
IAPMOInternational Associates of Plumbing and Mechanical Officials
IRWMPIntegrated regional watershed management plan
LAMPLocal Agency Management Program
LARWQCBLos Angeles Regional Water Quality Control Board
LRWQCBLahontan Regional Water Quality Control Board
M galMillion gallons
Mg/LMilligrams-per-liter
MPIMinutes per inch
MPNMost probable number
mslMean sea level
NOWTSNon-conventional onsite wastewater treatment systems
NPDESNational Pollutant Discharge Elimination System
NSFNational Sanitation Foundation
OWTSOnsite wastewater treatment systems
PCEPerchloroethylene
PEProfessional Engineer
PGProfessional Geologist
PS/GEProfessional Soil/Geotechnical Engineer
QCQualified Contractor
QPQualified Professional
REHSRegistered Environmental Health Specialist
RVRecreational vehicle
RWQCBRegional Water Quality Control Board
SNMPSalt and Nutrient Management Plan
SWAMPSurface Water Ambient Monitoring Program
SWRCBState Water Resources Control Board
SWTRSurface Water Treatment Rule
vi
WDRWaste Discharge Requirements
TCETrichloroethylene
TDSTotal dissolved solids
TKNTotal Kjeldahl Nitrogen
TMDLTotal maximum daily load
TNTotal Nitrogen
TSSTotal suspended solids
USDAUnited States Department of Agriculture
USEPAUnited States Environmental Protection Agency
WMAWastewater management area
WQAPWater Quality Assessment Program
WWTPWaste water treatment plants
vii
EXECUTIVE SUMMARY
Onsite wastewater treatment systems (OWTS) are useful and necessary structures that
allow habitation at locationsthat are removed from centralized wastewater treatment
systems. When properly sited, designed, operated, and maintained, OWTS treat
domestic wastewater to reduce its polluting impact on the environment and most
importantly protect public health. Estimates for the number of installations of OWTS in
California as of 2012 are that more than 1 million systems are installed and operating.
The vast majority of these are functioning in a satisfactory manner and meeting their
intended purpose.
However, there have been occasions in California where OWTS for a varied list of
reasons have not satisfactorily protected either water quality or public health. Some
instances of these failures are related to the OWTS not being able to adequately treat
and dispose of waste as a result of poor design or improper site conditions. Others have
occurred where the systems are operating as designed but their densities are such that
the combined effluent resulting from multiple systems is more than can be assimilated
into the environment. From these failures we must learn how to improve our usage of
OWTS and prevent such failures from happening again.
As California’s population continues to grow, and we see both increased rural housing
densities and the building of residences and other structures in more varied terrain than
we ever have before, we increase the risks of causing environmental damage and
creating public health risks from the use of OWTS. What may have been effective in the
past may not continue to be as conditions and circumstances surrounding particular
locations change. So necessarily more scrutiny of our installation of OWTS is demanded
of all those involved, while maintaining an appropriate balance of only the necessary
requirements so that the use of OWTS remains viable.
The State Water Resources Control Board (SWRCB) prepared a Water Quality Control
Policy for Siting, Design, Operation and Maintenance of Onsite Wastewater Treatment
Systems, dated June 19, 2012, also referred to as the “OWTS Policy” (SWRCB, 2012).
The purpose of the OWTS Policy is to allow the continued use of OWTS, while being
protective of water quality and public health. The OWTS Policy recognizes that
responsible local agencies can provide the most effective means to manage OWTS on a
routine basis. Therefore, as an important element, it is the intent of the OWTS Policy to
efficiently utilize and improve upon where necessary existing local programs through
coordination between the State and local agencies. To accomplish this purpose, the
OWTS Policy establishes a statewide, risk-based, tiered approach for the regulation and
management of OWTS installations and replacements and sets the level of performance
1
and protection expected from OWTS. In particular, the OWTS Policy requires actions for
water bodies specifically identified as part the OWTS Policy where OWTS contribute to
water quality degradation that adversely affect beneficial uses. The individual Tiers are
defined as follows:
Tier 0 –Existing OWTS: Existing OWTS that are properly functioning, and do not
meet the conditions of failing systems or otherwise require corrective action (for
example, to prevent groundwater impairment) as specifically described in Tier 4,
and are not determined to be contributing to an impairment of surface water as
specifically described in Tier 3, are automatically included in Tier 0.
Tier 1 –Low-Risk New or Replacement OWTS: New or replacement OWTS that
meet low risk siting and design requirements as specified in Tier 1, where there is
not an approved Local Agency Management Program per Tier 2. Los Angeles
County has a Local Agency Management Program; therefore, OWTS in Los
Angeles County will not qualify as Tier 1.
Tier 2 –Local Agency Management Program for New or Replacement OWTS:
California iswell known for its extreme range of geological and climatic conditions.
As such, the establishment of a single set of criteria for OWTS would either be too
restrictive so as to protect for the most sensitive case, or would have broad
allowances that would not be protective enough under some circumstances. To
accommodate this extreme variance, local agencies may submit management
programs (“Local Agency Management Programs”) for approval, and upon
approval then manage the installation of new and replacement OWTS under that
program. Local Agency Management Programs approved under Tier 2 provide an
alternate method from Tier 1 programs to achieve the same policy purpose, which
is to protect water quality and public health. In order to address local conditions,
Local Agency Management Programs may include standards that differ from the
Tier 1 requirements for new and replacement OWTS. Once the Local Agency
Management Program is approved, new and replacement OWTS that are included
within the Local Agency Management Program may be approved by the Local
Agency. A Local Agency, at its discretion, may include Tier 1 standards within its
Tier 2 Local Agency Management Program for some or all of its jurisdiction.
However, once a Local Agency Management Program isapproved, it shall
supersede Tier 1 and all future OWTS decisions will be governed by the Tier 2
Local Agency Management Program until it is modified, withdrawn, or revoked.
Tier 3 –Impaired Areas: Existing, new, and replacement OWTS that are near
impaired water bodies may be addressed by a Total Maximum Daily Load (TMDL)
and its implementation program, or special provisions contained in a Local Agency
2
Management Program. The TMDL and its implementation plan shall be
established by the US Environmental Protection Agency, or adopted by the County
as Basin Plan Amendment(s). If there is no TMDL or special provisions, new or
replacement OWTS within 600 feet of water bodies impaired for nitrogen or
pathogens must meet the specific requirements of Tier 3. Inthis Local Agency
Management Program (LAMP), OWTS near impaired waterbodies and new or
replacement OWTS within 600 feet of water bodies impaired for nitrogen or
pathogens must meet the specific requirements of Tier 3, which includes
requirements for supplemental treatment as a non-conventional OWTS (NOWTS)
as well as inclusion in the Advanced Protection Management Program (APMP)
described in this LAMP.
Tier 4 –OWTS Requiring Corrective Action: OWTS that require corrective action
or are either presently failing or fail at any time while the OWTS Policy is in effect
are automatically included in Tier 4 and must follow corrective actions described
in the OWTS Policy. Under the OWTS Policy, Tier 4 OWTS must continue to meet
applicable requirements of Tier 0, 2 or 3 pending completion of corrective action.
Tier 4 OWTS that are brought into compliance with Tier 2 or Tier 3 requirements
may then be managed under this LAMP.
The OWTS Policy only authorizes subsurface disposal of domestic strength, and in limited
instances high strength wastewater, and establishes minimum requirements for the
permitting, monitoring, and operation of OWTS for protecting beneficial uses of waters of
the State and preventing or correcting conditions of pollution and nuisance. This LAMP
is intended to apply to all OWTS in Los Angeles County that have domestic wastewater
design flows of up to 10,000 gallons per day (gpd) and that are located within: (a)
unincorporated areas of Los Angeles County; (b) cities that contract with the County for
Building and Safety approval; and (c) any city that enters into an agreement with the
County for OWTS management pertaining to the LAMP.
For Tier 2 and Tier 3 OWTS that qualify for management under this LAMP as well as Tier
0 OWTS, the OWTS Policy conditionally waives the requirement for owners of OWTS to
apply to the local RWQCB office for and receive Waste Discharge Requirements (WDR)
in order to operate their systems when they meet the conditions set forth in the OWTS
Policy. Nothing in the OWTS Policy or this LAMP supersedes or requires modification of
TMDLs or Basin Plan prohibitions of discharges from OWTS.
Los Angeles County Codes Title 11 (Health and Safety) and Title 28 (Plumbing) detail the
regulation, design, installation, use and maintenance of OWTS in Los Angeles County.
The DPH published Requirements and Procedures for Conventional and Non-
Conventional Onsite Wastewater Treatment Systems (also referred to as the
3
“Professional Guide”), draft version dated May 2016, to detail requirements and
procedures for obtaining approval from the DPH when installing or renovating an OWTS
or NOWTS and when Tier 3 is required in Los Angeles County. These Codes and
Professional Guide accompany and help form the basis for this LAMP. The May 2018
Professional Guide incorporates requirements from this LAMP. If discrepancies arise
between the LAMP, Professional Guide and Codes, the more restrictive requirement will
apply. The LAMP and Professional Guide comply with the OWTS Policy. The County is
adopting subdivision density specifications from Tier 1 of the OWTS Policy in this LAMP,
as shown in this LAMP and the Professional Guide. The Codes also comply with the
OWTS Policy, except for some horizontal setback minimum requirements not currently
specified, which will be amended to the Plumbing Code.
TableE-1.Allowable Average Densities per Subdivision
Average Annual Rainfall Allowable Density
(in/yr)(acres/single family dwelling
unit)
0–152.5
>15 –202
>20 –251.5
>25 –351
>35 –400.75
>400.5
TableE-2. Minimum Horizontal Setback Distances
Minimum Horizontal
Septic Disposal Seepage
Distance in Clear Required
TankFieldPit
From:
5 feet 8 feet 8 feet
1
Buildings or Structures
(1.52m)(2.44m)(2.44m)
Property line adjoining 5 feet 5 feet 8 feet
private property(1.52m)(1.52m)(2.44m)
Public Water Well, Where
200
depth of effluent dispersal —200 (61m)
9
(61m)
8,9
system >10 feet
Public Water Well, Where
150 feet 150 feet
depth of effluent dispersal —
(45.7m)(45.7m)
8
107,107,10
Springs, and Flowing 100 feet100 feet150 feet
8,10
Surface Water(30.5m)(30.5m)(45.7m)
Vernal Pools, Wetlands,
117,117,11
Lakes, Ponds, or Other (Non-200 feet200 feet200 feet
Flowing) Surface Water (61m)(61m)(61m)
8,11
Bodies
4
Minimum Horizontal
Septic Disposal Seepage
Distance in Clear Required
TankFieldPit
From:
5 feet 5 feet 12 feet
Seepage pits
(1.52m)(1.52m)(3.66m)
4
5 feet 4 feet5 feet
Disposal field
(1.52m)(1.22m)(1.52m)
On site domestic water 5 feet 5 feet 5 feet
service line(1.52m)(1.52m)(1.52m)
5 feet 5 feet
Distribution box—
(1.52m)(1.52m)
10 feet 10 feet 10 feet
Pressure public water main
(3.05m)(3.05m)(3.05m)
100 feet 100 feet 150 feet
8
Private Water Wells
(30.5m)(30.5m)(45.72 m)
100 feet 100 feet 100 feet
12
Monitoring wells
(30.5m)(30.5m)(30.5m)
Unstable Land Mass or
100 feet 100 feet 100 feet
Areas Subject to Earth
(30.5m)(30.5m)(30.5m)
13
Slides
High Water Mark of
400
Reservoir, Lake, or Flowing 400 (122m)400 (122m)
(122m)
14
Water Body, Type I
High Water Mark of
Reservoir, Lake, or Flowing 200 (61m)200(61m)200 (61m)
15
Water Body, Type II
10 feet 10 feet 10 feet
16
Trunk of any tree
(3.05m)(3.05m)(3.05m)
Notes: See Table 3-4 for the detailed notes 1-16 regarding horizontal setbacks in
this table.
The Los Angeles Regional Water Quality Control Board (LARWQCB), the Lahontan
Regional Water Quality Control Board (LRWQCB) and the SWRCB acknowledge that the
County of Los Angeles, its elected officials, officers, employees, and agents (County)
shall not be liable for any harm, loss, injury, death, or other damages arising out of
County's administration of the program.
5
1.0 INTRODUCTION AND BACKGROUND
1.1 Introduction
ThisdocumentpresentstheproposedLocalAgencyManagementProgram
(LAMP)foroversightofonsitewastewatertreatmentsystems(OWTS)withinthe
CountyofLos Angeles,California. ThisLAMPhasbeenpreparedinaccordance
withtherequirementsofthe StateWaterResourcesControlBoard’s(SWRCB)
WaterQualityControlPolicyforSiting,Design,OperationandMaintenanceof
OnsiteWastewaterTreatmentSystems,datedJune19,2012, alsoreferredtoas
the“OWTSPolicy” (SWRCB, 2012).
The SWRCB’sOWTSPolicyprovidesamulti-tieredstrategyofmanagementof
OWTSin California. ThisLAMPhasbeenpreparedbyLos AngelesCountyto
obtainapprovalforOWTS managementfor new and replacement OWTS under
Tier2oftheOWTSPolicy and for existing, new and replacement OWTS near
impaired water bodies under Tier 3 of the OWTS Policy.As described in the LAMP,
Los Angeles Countyintends tocontinueto providelocaloversightofOWTSby
implementingpracticesthat:(a) aresuitedtolocal conditions;(b)meet orexceed
environmental protectionsofthe “default”sitinganddesign requirementsfor
OWTSunderTier1oftheSWRCB’s OWTS Policy; and(c)ensurethebest
opportunityforcoordinatedandcomprehensive managementofOWTS, public
healthandwaterqualityin Los AngelesCounty.
ThisLAMPisintendedtoapplytoallOWTSin Los Angeles County that have
domestic wastewaterdesign flowsofupto10,000gallons per day (gpd) and that
are located within: (a) unincorporated areas of Los AngelesCounty; (b) cities that
contract with the County for Building and Safety approval;and (c) any city that
enters into an agreement with the County for OWTS management pertaining to the
LAMP. Domestic wastewater includes all OWTS with domestic strength waste
including single family dwellings, apartments, office buildings and some
restaurants. This LAMP does not apply to OWTS located onStateandFederally-
owned lands.
AnyOWTSwith a design flowexceeding10,000gpdwould be regulatedbythe
respectiveCaliforniaRegional WaterQualityControlBoard (RWQCB).The County
will refer the applicant to the respective RWQCB for the issuance of a Waste
Discharge Requirements (WDR).Design and sitting of those OWTS will still fall
under the purview of the County.Californialaw providesthat a countyhealth
officerorcomprehensiveenvironmentalagencyisresponsibleforpermittingthe
installationofandregulatingOWTSwithinitsjurisdictionalboundaries (California
6
Health and Safety Code, §§ 116275; 116500).InLos AngelesCounty,theHealth
OfficerhasdesignatedtheDirectorofEnvironmentalHealth (“the Director”) and
all Environmental Health Specialists working for Los Angeles County asDeputy
HealthOfficersforthepurposeofenforcingStateandlocalenvironmentalhealth
law.With the exception of Long Beach, Pasadena and Vernon,all citieswithin
theCountyhavedesignatedtheCounty’sHealthOfficerastheirjurisdictions’
healthofficer.
1.1.1 Authority to Operate Program
It is the responsibility of the County of Los Angeles, Department of Public
Health (DPH), Environmental Health (EH)to protect health, prevent
disease, and promote the health and wellbeing for all persons in the County.
Within the DPH, the Environmental Health Division strives to promote health
and quality of life by identifying, preventing, and controlling harmful
environmental factors in Los Angeles County.
The OWTS Policy (formerly known as Assembly Bill 885) became effective
on May 13, 2013. The OWTS Policy mandates the adoption of additional
wastewater treatment and groundwater monitoring requirements. The
purpose of the OWTS Policy is to allow the continued use of OWTS, while
protecting water quality and public health. The OWTS Policy recognizes
that responsible local agencies can provide the most effective means to
manage OWTS on a routine basis. The OWTS Policy requirements are
incorporated into this LAMP, which is projected to be approved within 2
years of submittal.
The OWTS Policy conditionally waives the requirement for owners of OWTS
to apply for and receive Waste Discharge Requirements (WDR) in order to
operate their systems when they meet the conditions set forth in the Policy.
To receive coverage under the OWTS Policy and the included waiver of
waste discharges, OWTS will only accept and treat flows of domestic
wastewater with a design flow that does not exceed 10,000 gpd. In addition,
OWTS that accept high-strength wastewater from commercial food service
buildings are covered under the OWTS Policy and the waiver of waste
discharge requirements if the wastewater does not exceed 900 mg/L BOD
and there is a properly sized and functioning oil/grease interceptor (a.k.a
grease trap). Nothing in this LAMP or the OWTS Policy supersedes or
requires modification of TMDLs or Basin Plan prohibitions of discharges
from OWTS.
7
The DPH provides guidelines for preparation and submittal of siteor project
specific plans and feasibility reports in accordance with the Los Angeles
County Code, Title 11 (Health and Safety) and Title 28 (Plumbing) and other
regulations applicable to OWTS, in order to obtain approval for construction
and installation of an OWTS or non-conventional OWTS (NOWTS) in the
County.
All requirements in this LAMP are subject to amendments when deemed
necessary by the DPH and in accordance with the OWTS Policy. The DPH
will make every effortto notify the related industry and all interested parties
of any revisions to these guidelines 30 days prior to the effective date of the
implementation. This LAMP does not represent all applicable regulations
in their entirety; other requirements may apply.
Applicants who have been denied an approval by the DPH under the LAMP
regulations may apply to the Regional Water Board for the issuance of a
Wastewater Discharge Requirement (WDR). A WDR is still subject to the
jurisdictional Building and Safety requirements for the installation of
OWTS/NOWTS.
1.1.2 Definitions
The following definitions apply to this LAMP:
“303 (d) list”means the same as “Impaired Water Bodies.”
“At-grade system”means an OWTS dispersal system with a discharge
point located at thepreconstruction grade (ground surface elevation). The
discharge from an at-grade system is always subsurface.
“Average annual rainfall”means the average of the annual amount of
precipitation for a location over a year as measured by the nearest National
Weather Service station for the preceding three decades. For example the
data set used to make a determination in 2012 would be the data from 1981
to 2010.
“Basin Plan”means the same as “water quality control plan” as defined in
Division 7 (commencingwith Section 13000) of the Water Code. Basin
Plans are adopted by each Regional Water Board, approved by the State
Water Board and the Office of Administrative Law, and identify surface
water and groundwater bodies within each Region’s boundaries and
8
establish, for each, its respective beneficial uses and water quality
objectives. Copies are available from the Regional Water Boards,
electronically at each Regional Water Boards website, or at the State Water
Board’s Plans and Policies web page
(http://www.waterboards.ca.gov/plans_policies/).
“Bedrock”means the rock, usually solid, that underlies soil or other
unconsolidated, surficial material. Bedrock includes igneous, metamorphic,
and sedimentary rock formations.
“CEDEN”means California Environmental Data Exchange Network and
information about itis available at the State Water Boards website or
.
http://www.ceden.org/index.shtml
“Cesspool”means an excavation in the ground receiving domestic
wastewater, designed to retain the organic matter and solids, while allowing
the liquids to seep into the soil. Cesspools differ from seepage pits because
cesspool systems do not have septic tanks and are not authorized under
the OWTS Policy. The term cesspool does not include pit-privies and out-
houses which are not regulated under the OWTS Policy.
“Clay”means a soil particle; the term also refers to a type of soil texture.
As a soil particle, clay consists of individual rock or mineral particles in soils
having diameters <0.002 mm. As a soil texture, clay is the soil material that
is comprised of 40 percent or more clay particles, not more than 45 percent
sand and not more than 40 percent silt particles using the USDA soil
classification system.
“Cobbles”means rock fragments 76 mm or larger using the USDA soil
classification systems.
“Dispersal system”means a leachfield, seepage pit, mound, at-grade,
subsurface drip field, evapotranspiration and infiltration bed, or other type
of system for final wastewater treatment and subsurface discharge.
“Domestic wastewater” means wastewater with a measured strength less
then high-strength wastewater and is the type of wastewater normally
discharged from, or similar to, that discharged from plumbing fixtures,
appliances and other household devices including, but not limited to toilets,
bathtubs, showers, laundry facilities, dishwashing facilities, and garbage
9
disposals. Domestic wastewater may include wastewater from commercial
buildings such as office buildings, retail stores, and some restaurants, or
from industrial facilities where the domestic wastewater is segregated from
the industrial wastewater. Domestic wastewater may include incidental RV
holding tank dumping but does not include wastewater consisting ofa
significant portion of RV holding tank wastewater such as at RV dump
stations. Domestic wastewater does not include wastewater from industrial
processes.
“Dump Station” means a facility intended to receive the discharge of
wastewater from a holding tank installed on a recreational vehicle. A dump
station does not include a full hook-up sewer connection similar to those
used at a recreational vehicle park.
“Domestic well” means a groundwater well that provides water for human
consumption and is not regulated by the State Water Resources Control
Board, Division of Drinking Water.
“Earthen material” means a substance composed of the earth’s crust (i.e.
soil and rock).
“EDF” see “electronic deliverable format.”
“Effluent” means sewage, water, or other liquid, partially or completely
treated or in its natural state, flowing out of a septic tank, aerobic treatment
unit, dispersal system, or other OWTS component.
“Electronic deliverable format” or “EDF” means the data standard
adopted by the State Water Board for submittal of groundwater quality
monitoring data to the State Water Board’s internet-accessible database
).
system Geotracker (http://geotracker.waterboards.ca.gov/
“Escherichia coli” means a group of bacteria predominantly inhabiting the
intestines of humans or other warm-blooded animals, but also occasionally
found elsewhere. Used as an indicator of human fecal contamination.
“Existing OWTSas defined by the State OWTS Policy”means an
OWTS that was constructed and operating prior to the effective date of the
OWTS Policy, and OWTS for which a construction permit has been issued
prior to the effective date of the Policy.The effective date of the OWTS
10
Policy is May 13, 2013. In all other situations, existing OWTS is any
constructed and operating OWTS.
“Feasibility Study”means the documents, test results, geological reports,
etc. that are required to be prepared and submitted in order to demonstrate
the feasibility of installing an OWTS or NOWTS, including the 100% future
expansion area.
“Flowing water body” means a body of running water flowing over the
earth in a natural water course, where the movement of the water is readily
discernible or if water is not present it is apparent from review of the geology
that when present it does flow, such as in an ephemeral drainage, creek,
stream, or river.
“Groundwater” means water below the land surface that is at or above
atmospheric pressure.
“High-strength wastewater” means wastewater having a 30-day average
concentration of biochemical oxygen demand (BOD) greater than 300
milligrams-per-liter (mg/L) or of total suspended solids (TSS) greater than
330 mg/L orfats, oil, and grease (FOG) concentration greater than 100
mg/L prior to the septic tank or other OWTS treatment component.
“IAPMO” means the International Association of Plumbing and Mechanical
Officials.
“Impaired Water Bodies” means those surface water bodies or segments
thereof that are identified on a list approved first by the State Water Board
and then approved by US EPA pursuant to Section 303(d) of the federal
Clean Water Act.
“Local agency” means any subdivision of state government that has
responsibility for permitting the installation of and regulating OWTS within
its jurisdictional boundaries; typically a county, city, or special district.
“Major repair” means either: (1) for a dispersal system, repairs required
for an OWTS dispersal system due to surfacing wastewater effluent from
the dispersal field and/or wastewater backed up into plumbing fixtures
because the dispersal system is not able to percolate the design flow of
wastewater associated with the structure served, or (2) for a septic tank,
11
repairs required to the tank for a compartment baffle failure or tank structural
integrity failure such that either wastewater is exfiltrating or groundwater is
infiltrating.
“Mottling” means a soil condition that results from oxidizing or reducing
minerals due to soil moisture changes from saturated to unsaturated over
time. Mottlingis characterized by spots or blotches of different colors or
shades of color (grays and reds) interspersed within the dominant color as
described by the USDA soil classification system. This soil condition can
be indicative of historic seasonal high groundwater level, but the lack of this
condition may not demonstrate the absence of groundwater.
“Mound system” means an aboveground dispersal system (covered sand
bed with effluent leachfield elevated above original ground surface inside)
used to enhance soil treatment, dispersal, and absorption of effluent
discharged from an OWTS treatment unit such as a septic tank. Mound
systems have a subsurface discharge.
“New OWTS” means an OWTS permitted after the effective date of the
OWTS Policy.
“NOWTS” means a non-conventional OWTS. It provides additional
treatment of the effluent to reduce Nitrogen (N), Total Suspended Solids
(TSS), and the Biological Oxygen Demand (BOD). It may also provide
disinfection against pathogens, and alternate methods of effluent dispersal.
NOWTS corresponds to the Tier 3 OWTS described in the OWTS Policy
and any OWTS with a requirement for supplemental treatment.
“NSF” means NSF International (a.k.a. National Sanitation Foundation), a
not for profit, non-governmental organization that develops health and
safety standards and performs product certification.
“Oil/grease interceptor” means a passive interceptor that has a rate of
flow exceeding 50 gallons-per-minute and that is located outside a building.
Oil/grease interceptors are used for separating and collecting oil and grease
from wastewater.
“Onsite wastewater treatment system(s)” (OWTS) means individual
disposal systems, community collection and disposal systems, and
collection and disposal systems that use subsurface disposal. The short
12
form of the term may be singular or plural. OWTS do not include “graywater”
systems pursuant to Health and Safety Code Section 17922.12.
“Percolation test” means a method of testing water absorption of the soil.
The test is conducted with clean water and test results can be used to
establish the dispersal system design.
“Permit” means a document issued by a local agency that allows the
installation and use of an OWTS, or waste discharge requirements or a
waiver of waste discharge requirements that authorizes discharges from an
OWTS.
“Person” means any individual, firm, association, organization,
partnership, business trust, corporation, company, State agency or
department, or unit of local government who is, or that is, subject to the
OWTSPolicy.
“Pit-privy” (a.k.a. outhouse, pit-toilet) means self-contained waterless
toilet used for disposal of non-water carried human waste; consists of a
shelter built above a pit in the ground into which human waste falls.
“Policy” means the OWTS Policy for Siting, Design, Operation and
Management of OWTS.
“Pollutant” means any substance that alters water quality of the waters of
the State to a degree that it may potentially affect the beneficial uses of
water, as listed in a Basin Plan.
“Projected flows” means wastewater flows into the OWTS determined in
accordance with any of the applicable methods for determining average
daily flow in the USEPA Onsite Wastewater Treatment System Manual,
2002, or for Tier 2 in accordance with an approved Local Agency
Management Program.
“Public Water System” is a water system regulated by the State Water
Resources Control Board, Division of Drinking Water or a Local Primacy
Agency pursuant to Chapter 12, Part 4, California Safe Drinking Water Act,
Section 116275 (h) of the California Health and Safety Code.
13
“Public Water Well” is a ground water well serving a public water system.
A spring which is not subject to the California Surface Water Treatment Rule
(SWTR), CCR, Title 22, sections 64650 through 64666 is a public well.
“Qualified professional” means an individual licensed or certified by a
State of California agency to design OWTS and practice as professionals
for other associated reports, as allowed under their license or registration.
Depending on the work to be performed and various licensing and
registration requirements, this may include an individual who possesses a
registered environmental health specialist certificate or is currently licensed
as a professional engineer or professional geologist. For the purposes of
performing site evaluations, Soil Scientists certified by the Soil Science
Society of America are considered qualified professionals. A local agency
may modify this definition as part of its Local Agency Management Program.
“Regional WaterBoard” is any of the Regional Water Quality Control
Boards designated by Water Code Section 13200. Any reference to an
action of the Regional Water Board in the OWTS Policy also refers to an
action of its Executive Officer, including the conducting of public hearings,
pursuant to any general or specific delegation under Water Code Section
13223.
“Replacement OWTS” means an OWTS that has its treatment capacity
expanded, or its dispersal system replaced or added onto, after the effective
date of the OWTS Policy.
“Sand” means a soil particle; this term also refers to a type of soil texture.
As a soil particle, sand consists of individual rock or mineral particles in soils
having diameters ranging from 0.05 to 2.0 millimeters. As a soil texture,
sand is soilthat is comprised of 85 percent or more sand particles, with the
percentage of silt plus 1.5 times the percentage of clay particles comprising
less than 15 percent.
“Seepage pit” means a drilled or dug excavation, three to six feet in
diameter, either lined or gravel filled, that receives the effluent discharge
from a septic tank or other OWTS treatment unit for dispersal.
“Septic tank” means a watertight, covered receptacle designed for primary
treatment of wastewater and constructed to:
1. Receive wastewater discharged from a building;
14
2. Separate settleable and floating solids from the liquid;
3. Digest organic matter by anaerobic bacterial action;
4. Store digested solids; and
5. Clarify wastewater for further treatment with final subsurface discharge.
“Service provider” means a person capable of operating, monitoring, and
maintaining an OWTS in accordance to the OWTS Policy.
“Silt” means a soil particle; this term also refers to a type of soil texture. As
a soil particle, silt consists of individual rock or mineral particles in soils
having diameters ranging from between 0.05 and 0.002 mm. As a soil
texture, silt is soil that is comprised as approximately 80 percent or more silt
particles and not more than 12 percent clay particles using theUSDA soil
classification system.
“Single-family dwelling unit” means a structure that is usually occupied
by just one household or family and for the purposes of the OWTS Policy is
expected to generate an average of 250 gallons per day of wastewater.
“Site” means the location of the OWTS and, where applicable, a reserve
dispersal area capable of disposing 100 percent of the design flow from all
sources the OWTS is intended to serve.
“Site Evaluation” means an assessment of the characteristics of the site
sufficient to determine its suitability for an OWTS to meet the requirements
of the OWTS Policy.
“Soil” means the naturally occurring body of porous mineral and organic
materials on the land surface, which is composed of unconsolidated
materials, including sand-sized, silt-sized, and clay-sized particles mixed
with varying amounts of larger fragments and organic material. The various
combinations of particles differentiate specific soil textures identified in the
soil textural triangle developed by the United States Department of
Agriculture (USDA) as found in Soil Survey Staff, USDA; Soil Survey
Manual, Handbook 18, U.S. Government Printing Office, Washington, DC,
1993, p. 138. For the purposes of the OWTS Policy, soil will contain earthen
material ofparticles smaller than 0.08 inches (2 mm) in size.
15
“Soil Structure” means the arrangement of primary soil particles into
compound particles, peds, or clusters that are separated by natural planes
of weakness from adjoining aggregates.
“Soil texture” means the soil class that describes the relative amount of
sand, clay, silt and combinations thereof as defined by the classes of the
soil textural triangle developed by the USDA (referenced above).
“State Water Board” is the State Water Resources ControlBoard.
“Supplemental treatment” means any OWTS or component of an OWTS,
except a septic tank or dosing tank, that performs additional wastewater
treatment so that the effluent meets a predetermined performance
requirement prior to discharge of effluent into the dispersal field.
“SWAMP” means Surface Water Ambient Monitoring Program and more
information is available at:
http://www.waterboards.ca.gov/water_issues/programs/swamp/
“Telemetric” means the ability to automatically measure and transmit
OWTS data by wire, radio, or other means.
“TMDL” is the acronym for “total maximum daily load.” Section 303(d)(1) of
the Clean Water Act requires each State to establish a TMDL for each
impaired water body to address the pollutant(s) causing the impairment. In
California, TMDLs are usually adopted as Basin Plan amendments and
contain implementation plans detailing how water quality standards will be
attained.
“Total coliform” means a group of bacteria consisting of several genera
belonging to the family Enterobacteriaceae, which includes Escherichia coli
bacteria.
“USDA” means the U.S. Department of Agriculture.
“Waste discharge requirement” or “WDR” means an operation and
dischargepermit issued for the discharge of waste pursuant to Section
13260 of the California Water Code.
16
1.2 Geographical Area
th
While listed as the 74largest county by area in the United States (U.S.), as of the
2014 U.S. Census Bureau’s Population Estimates Program (PEP), the County has
a reported population of 10,116,705, making it by far the most populous county in
the U.S. The County seat is the City of Los Angeles. Los Angeles County is bound
to the northwest by Ventura County, to the north by Kern County, to the east by
San Bernardino County and to the southeast by Orange County.
According to the U.S. Census Bureau, the County has a total area of 4,751 square
22
miles (12,310 km), of which 4,083 square miles (10,570 km) is land and 693
2
square miles (1,790 km) (15%) is surface water. Los Angeles County includes 70
miles (110 km) of coastline along the Pacific Ocean and encompasses towering
mountain ranges, deep valleys, forests, islands, lakes, rivers and desert areas.
The Los Angeles River, Rio Hondo, the San Gabriel River and the Santa Clara
River flow within Los Angeles County, while the Santa Monica Mountains and the
San Gabriel Mountains arethe primary mountain ranges. The western extent of
the Mojave Desert begins in the Antelope Valley, in the northeastern part of the
County. San Clemente Island and Santa Catalina Island, part of the Channel
Islands archipelago, are located off the coast.
Los Angeles County has 88 incorporated cities and many unincorporated areas.
2
At 4,083 square miles (10,570 square kilometers (km), it is larger than the
combined areas of the states of Rhode Island and Delaware. The County contains
more than one quarter of all California residents and is one of the most ethnically
diverse counties in the state and the country. Most of the population of Los
Angeles County is located in the south and southwest, with major population
centers in the Los Angeles Basin, SanFernando Valley and San Gabriel Valley.
Other population centers are found in the Santa Clarita Valley, Pomona Valley,
Crescenta Valley and Antelope Valley.
Los Angeles County is divided west-to-east by the rugged San Gabriel Mountains,
filled with coniferous forests and subject to plentiful snowfall in the winter. The San
Gabriel Mountains are part of the Transverse Ranges of southern California and
are contained mostly within the Angeles National Forest. Most of the highest
peaks in the County are located in the San Gabriel Mountains, including Mount
San Antonio 10,068 feet (3,069 meters (m) at the Los Angeles-San Bernardino
county lines, Mount Baden-Powell 9,399 feet (2,865 m), Mount Burnham 8,997
feet (2,742 m) and the well-known Mount Wilson 5,710 feet (1,740 m) where the
Mount Wilson Observatory is located. Several smaller, lower mountains are
located in the northern, western and southwestern parts of the County, including
17
the San Emigdio Mountains, the southernmost part of Tehachapi Mountains and
the Santa Monica Mountains.
1.3 RegulationofOnsiteWastewaterTreatmentSystems (OWTS)
The County of Los Angeles, Department of Public Health (DPH), Environmental
Health (EH) is responsible for regulating OWTS throughout: (a) unincorporated
areas of LosAngeles County; (b) cities that contract with the County for Building
and Safety approval; and (c) any city that enters into an agreement with the County
for OWTS management pertaining to the LAMP. Currently, eleven (11) cities have
entered into agreements with DPH for management of OWTS, including, Agoura
Hills, Bradbury, La Canada-Flintridge, La Habra Heights, Lynwood, Palos Verdes
Estates, Rolling Hills, Rolling Hills Estates, Lancaster, Palmdale and Walnut.
OWTS are used almost exclusively for properties located outside of municipal
sewer service boundaries, which includes large areas in the northern and
northeastern portions of the County, as well as in the mountain regions. For select
OWTS systems, DPH requires supplemental treatment so that effluent meets a
predetermined performance requirement, and refers to these systems with
supplemental treatment as nonconventional OWTS (NOWTS). DPH administers
OWTS (including NOWTS) regulations within its jurisdiction. Countywide there are
currently estimated to be 53,148 OWTS and 813 NOWTS.
The County has historically operated its OWTS program under the authority
granted to it by two California Regional Water Quality Control Boards (RWQCBs):
(1) Lahontan Region 6 for areas that drain the northeastern regionsof the County;
and (2) the Los Angeles Region 4 for the remaining areas of the County including
Santa Catalina and San Clemente Islands. Figure 1-1is a map of Los Angeles
County, showing the areas of the heaviest concentration of OWTS, major
watersheds and the RWQCB boundaries. Figure 1-2shows a similar map for the
areas of the heaviest concentration of NOWTS
1.4 Los Angeles CountyCodes Applicable to OWTS
Los Angeles County Codes Title 11 (Health and Safety) and Title 28 (Plumbing)
detail the regulation, design, installation,useandmaintenanceofOWTS inLos
Angeles County(summarizedbelow). Along with the Los Angeles County
Professional Guide described in Section 1.5, these codes accompany and help
formthebasisforthis LAMP.Table1-1presentsabriefsynopsisofvarious
sectionsofthese codes.
18
Table1-1.Los AngelesCountyOWTS Codes Summary
County of Los Angeles Health and Safety Code (Title 11)
Chapter 11.02 –This chapter describes general provisions and definitions under the
General Provisions Health Code, including, but not limited to, the authority of the director of
and Definitionspublic health, powers of deputies, and maximum punishment for
violations under Title 11. This chapter includes provisions intended to
supplement the laws and regulations of the state of California by
prescribing higher standards of sanitation, health and safety.
Chapter 11.20 –These sections provide definitions related to housing.
Housing, Sections
11.20.010 through
11.20.140
Chapter 11.38 –Plan review and permit requirements for waste disposal systems.
Water and Sewers, Provides location specifications for private sewage disposal systems.
Section 11.38.450 This chapter will be updated with an ordinance to implement the LAMP.
and 11.38.470
Chapter 11.54 –This section describes general hazards associated with wells, test
Wells, Test Holes, holes, cesspools, cisterns and septic tanks.
Cesspools,
Cisterns and
Septic Tanks
Chapter 11.56 –Describes provisions for hearings and enforcement, including for
Hearings and nuisance abatement.
Enforcement
County of Los Angeles Plumbing Code (Title 28)
Chapter 1 –Describes administration of the plumbing code, which is intended to
Administrationprovide minimum standards to preserve the public health, safety and
welfare by regulating the design, construction, quality of material, and
installation of plumbing.
Chapter 3 –The design of the OWTS system will comply with minimum standards,
General including accepted plumbing material standards, as specified in Chapter
Regulations3.
Appendix HPertinent minimum horizontal set-back distances in Table H-1. All
components of OWTS will be installed in accordance with the setback
requirements for “stream” as prescribed in Table H-1. Notwithstanding,
the total capacity for thetank, whether combined with the supplemental
treatment unit as one tank or separate from the supplemental treatment
unit as a trash tank will meet or exceed the capacity requirements as
prescribed in Table H-2.
21
1.5 Los Angeles CountyRequirements and Procedures for OWTS and NOWTS
(Professional Guide)
The DPH published Requirements and Procedures for Conventional and Non-
Conventional Onsite Wastewater Treatment Systems (also referred to as the
“Professional Guide”), draft version datedMay 2016, to detail requirements and
procedures for obtaining approval from the DPH when installing or renovating an
Onsite Wastewater Treatment System (OWTS) and when a Nonconventional
Onsite Wastewater Treatment System (NOWTS) is required in Los Angeles
County (summarized below). The May 2018 Professional Guide incorporates
requirements from this LAMP. Along with the Los Angeles County Health and
Safety Code and Plumbing Code described in Section 1.4, this Professional Guide
accompanies and helps form the basis for this LAMP.
TheProfessional Guidedescribes thepolicy,proceduralandtechnicaldetailsfor
implementationofthe Codes.It includesan approval process flowchart, plan
submittal checklist, service request application (including fees), and technical
requirements for OWTS and NOWTS. TheProfessional Guidewill be reviewedand
updatedfromtime-to-time, typicallyevery three years,to ensure that OWTS and
NOWTS continue to sufficiently treat domestic wastewater to reduce its polluting
impact on the environment and most importantly protect public health. The
Professional Guidewillbemaintained bythe DPH. TheProfessional Guide
document submittedwith this LAMP, aswell asanysubstantive changesinthe
futurewillrequire approvalbythe Directorof EH and by theRWQCB.
The Professional Guideisdividedinto fourteen main chaptersasfollows:
1.Projects That Require Plan Review and Feasibility Reports.Thischapter
details the types of projects requiring plan review and feasibility reports
where a public sewer is not available, includingsubdivision,new
construction,expansion, remodel andsystemrepair projects.
2.Professional Qualifications for Preparing Feasibility Reports and
Installation of OWTS.This chapter describes the professional requirements
of a Qualified Professional (QP) for preparation of feasibility reports and OWTS
design. Additionally, this chapter describes the professional requirementsof a
Qualified Contractor (QC) for OWTS construction and repairs.
3.Documents and Information Required for OWTS Plan Review.This
chapter discusses important information required in the service request
application, feasibility report, floor plan, grading plan, plot plan, cross-sectional
view, and site identification.
22
4.Setbacks and Other Considerations. This chapter describes the setback
requirements for OWTS and NOWTS installations and the procedures to obtain
a waiver for certain setbacks.
5.Septic Tank Capacity and Requirements. This chapter describes the design,
installation, maintenance and monitoring requirements for septic tanks with
references to the Plumbing Code.
6.Approved Dispersal Methods for Conventional OWTS. This chapter
presents requirements fordesignandconstructionofdispersalsystems, leach
beds, leach lines, infiltration chambers, seepage pits, and gravel-packed pits.
7.Future Expansion Area. This chapter details requirements for sufficient land
area to allow for an entirely new dispersal system (e.g., 100% future expansion
area) and when this requirement may be waived. Inspection, testing, failure,
and a 10% expansion of the current footprint rule related to the future
expansion area are also described in this chapter. Where adequate land is not
available for a 100% future expansion area, supplemental treatment (e.g.,
NOWTS) will be required.
8.Determining Depth of Groundwater. This chapter describes procedures for
site evaluation, permitting and subsurface exploration for determining the depth
of groundwater, including high groundwater situations.
9.Requirements Applicable to All Percolation Testing Types. This chapter
explains the percolation test requirements and procedures for properties with
proposed OWTS, noting that plan approval of the construction proposal will
expire one year from the date of the approval.
10.Percolation Testing for Leach Lines and Leach Bed Dispersal Systems.
This chapter explains the requirements and procedures for percolation tests for
leach lines and leach bed dispersal systems, along with related percolation rate
calculations.
11.Percolation Testing for Seepage Pit Dispersal Systems. This chapter
explains the requirements and procedures for percolation tests for seepage pit
dispersal systems, along with related percolation rate calculations.
Considerations for gravel packed pits are also included in this chapter. When
percolation testing holes cannot be filled to presoak or to conduct a
conventional percolation test due to drainage of water from the hole, the
maximum absorption capacity allowed by the Plumbing Code is considered to
be exceeded, and supplemental treatment is required.
23
12.Non-Conventional Onsite Wastewater Treatment Systems Requirements.
Conditions warranting supplemental treatment are described in this chapter,
i.e., when a NOWTS is required. A NOWTS is used to protect the groundwater
in areas where soil percolates too fast for sufficient natural filtration to occur.
Supplemental treatment is also required when a conventional system fails and
a replacement system cannot meet the current requirements or setbacks for
surface and ground water. This chapter includes requirements for design,
demonstration, approval, operation, monitoring, laboratory testing,
maintenance, inspection and reporting for NOWTS. Soil replacement
conditions, required soil depths, component/tank certification requirements and
effluent concentration limits are provided. This chapter describes situations
when neither an OWTS nor NOWTS are permitted as well.
13.NOWTS Start up and Leak Test. This chapter provides the requirement for a
NOWTS to pass a DPH leak test and final/start-up inspection before obtaining
approval from a Building and Safety Department Inspector. Procedures and
guidelines for leak testing and inspection are described in this chapter.
14.Sub-division Limitations. This chapter describes limitations on allowable
average densities for land development projects including Conditional Use
Permits and parcel sub-division projects where public sewer is not available
and that are proposed after the effective date of the LAMP.
1.6 OrganizationofthisLAMP
ThisLAMPisorganizedtoexplainthe design and management of OWTSinLos
Angeles County. Itisalsointended to document compliance with the SWRCB
OWTS Policy forLocalAgencyRequirements andResponsibilities(Section3.0of
theOWTSPolicy)andLocalAgencyManagementProgramforMinimumOWTS
9.0oftheOWTSPolicy).Referenceismadethroughout
Standards(Section
thisLAMPtotheLos Angeles County Health and Safety Code (Title 11), Plumbing
Code (Title 28) and Professional Guide (dated May 2016). The Professional Guide
is
attachedaspartofthisLAMP.Thefollowingbrieflysummarizesthecontents
ofthis document.
Section1–IntroductionandBackground. Thissectiondescribesthe
purpose,scope,geographicalarea, regulations, laws, guidance and
organization forthe LAMP.
Section 2–Environmental Conditions, OWTSUsageandWaterQuality
ManagementinLos AngelesCounty.Thissectionprovidesbackground
24
informationonenvironmental conditionsrelated toOWTS usage and
suitability. This section describes the extentofOWTSusageintheCountyand
summarizes water quality management measures.
Section3–OWTSSiting,DesignandConstructionRequirements.This
sectionpresents excerptsfromtheHealth and Safety Code, Plumbing Code
and Professional Guide summarizing requirementsfor siting, design and
constructionofOWTS, as per the requirements of the OWTS Policy.
Section 4 –SpecialManagementIssues. This section describes special
OWTS management issues in Los Angeles County, as per theOWTSPolicy.
Section5–Prohibitions.Thissectionpresents prohibitions in Los Angeles
County, as per prohibitionsin theOWTSPolicy.
Section6–ProgramAdministration.This section describes the plan for
maintaining records, water quality assessment and reporting to the RWQCB,
as per the OWTS Policy.
AppendixA–Supporting Rationale for Los Angeles County OWTS Siting
and Design Criteria.
Appendix B –Cumulative Nitrate and Salt Loading from OWTS in Los
Angeles County.
25
2.0 ENVIRONMENTALCONDITIONS,OWTSUSAGEANDWATERQUALITY
MANAGEMENTINLOS ANGELESCOUNTY
Thissectionprovidesbackgroundinformationonenvironmentalconditions,OWTS
usageand managementapproachesadoptedforprotectionofwaterqualityin Los
AngelesCounty.
2.1 SurfaceWaterHydrology
The surface water hydrology of Los Angeles County is influenced mainly by
topographical and land form conditions, climate, and water resources
management activities.
2.1.1Topography
The County of Los Angeles covers 4,751 square miles. The topography
within the County is 25 percent mountains, 10 percent coastal plain, and 65
percent foothills, valley, or desert. Elevations range from sea level to a
maximum of 10,068 feet at the summit of Mount San Antonio. The County
is divided into five principal drainage systems: Los Angeles River Basin,
San Gabriel River Basin, Santa Clara River Basin, Coastal Basin, and
Antelope Valley. The coastal plain slopes mildly and contains relatively few
depressions or natural ponding areas. The slopes of the main river systems
crossing the coastal plain, such as San Gabriel River, Los Angeles River,
and Ballona Creek, range from 4 to 14 feet per mile. The mountain ranges
within the County of Los Angeles are generally aligned in an east-west
direction and are part of the Transverse Ranges. The major range in the
County is the San Gabriel Mountains. Most of the mountainous areas lie
below 5,000 feet with only 210 square miles above this elevation. The
mountainous area is rugged. The deep “V”-shaped canyons with steep
walls are separated by sharp dividing ridges. The average slope of the
canyon floors ranges from 150 to 850 feet/mile in the San Gabriel
Mountains.
2.1.2Geology and Soils
Regional Setting:The present day geomorphic and geologic setting of Los
Angeles County is the result of the complex interaction between the Pacific
and North American Tectonic Plates that are obliquely colliding along a
right-lateral, strike-slip transform fault boundary system represented by the
San Andreas Fault and other related major fault systems. Both tensional
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forces and rotational compressive forces along this transform fault
boundary created deep structural depressions, or pull-apart basins, that
received thick deposits of Neogene-age sediments. These structural
depressions are separated by uplifted blocks or mountain ranges consisting
of Cretaceous and older sedimentary, metamorphic, and crystalline
basement rocks that are bounded by normal, reverse andthrust-fault
offsets.
Portions of three major geomorphic provinces occur within Los Angeles
County; the Transverse Ranges, Peninsula Ranges, and the Mojave
Desert. The primary geomorphic features within the east-west trending
Transverse Ranges in Los Angeles County include the San Gabriel,
Verdugo, and Santa Susana Mountains which are separated from the Santa
Monica Mountains by the San Fernando Valley. The north-south trending
Peninsular Geomorphic Province terminates against thrust faults that bound
the southern limits of the Transverse Province. The primary geomorphic
features of the Peninsular Ranges within Los Angeles County include the
Puente and San Jose Hills, as an extension of the Santa Ana Mountains,
the Coastal Plain, various uplifts related to the Newport-Inglewood
Structural Zone, and the Palos Verdes Hills. The San Gabriel and Upper
Santa Ana Valleys separate the Transverse Ranges from the peninsular
range in the east-central portion of the County. The primary geomorphic
feature of the Mojave Desert within Los Angeles County includes the high
desert and Antelope Valley.
Geologic Setting:Igneous, sedimentary, and metamorphic rock groups that
range in age from Precambrian to Holocene are present within the County.
Sedimentary and volcanoclastic rocks were deposited in marine and
continental depositional environments. The San Gabriel Mountains and
Verdugo Hills are composed primarily of highly fractured igneous rock, with
large outcrops of granitic rock exposed above coarse and porous alluvial
soils. Faulting and deep weathering have produced pervious zones in the
rock exposures. These rock masses have a comparatively shallow soil
mantle formed in part by accelerated erosion on the steep slopes. Other
mountainous and hilly areas within the County are composed primarily of
folded and faulted sedimentary rocks, including shale, sandstone, and
conglomerate, and volcanoclastic rocks. Residual soils in these areas are
shallow and are generally less permeable than those of the San Gabriel
Mountains. Valley and desert surface soils are alluvial and grade from
coarse sand and gravel near canyon mouths to silty clay and clay in the
lower valleys and coastal plain. The alluvium accumulates through
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repeated deposition of sedimentary material and reaches depths as great
as 18,000 feet in portions of the Coastal Plain. Where there is little clay,
this material is often quite porous. Impervious lenses and irregularities
divide the alluvium into several distinct groundwater basins. Valley soils are
generally well drained with relatively few perched water or artesian areas.
2.1.3Climate
The climate within the County varies greatly. The windward side of the San
Gabriel Mountain range is Mediterranean while the leeward side in the
Mojave Desert is arid. Precipitation, on average, is quite low. Most rain
occurs during winter and early spring, typical of a Mediterranean climate.
However, the amount received is usually lower than in other Mediterranean
climates. Precipitation during summer months is infrequent, and rainless
periods of several months are common. Average annual precipitation totals
for representative areas within the County vary from as little as 7.8 inches
in the Antelope Valley region, 15.5 inches in the Coastal Plain areas to 32.9
inches in the San Gabriel Mountains. However, the Los Angeles area is
also subject to the phenomena typical of a microclimate. As such, the
daytime temperatures can vary as much as 36°F (20°C) between inland
areas such as the San Fernando Valley and San Gabriel Valley versus the
coastal Los Angeles Basin.
2.1.4Coastal Plain and Mountain Areas
As discussed above, most precipitation in the Los Angeles area occurs in
the winter and early spring due to extratropical cyclones from the North
Pacific. Major storms consist of one or more frontal systems, extending 500
to 1,000 miles in length. The frontal systems can produce rainfall
simultaneously throughout the entire County, occasionally lasting four days
or longer. These storms approach Southern California from the west or
southwest with southerly winds that continue until the front passes. The
mountain ranges lie directly across the path of the inflowing warm, moist air.
The coastal and inland ranges cause the warm air to rise. As it rises,
precipitation forms and falls. This orographic effect intensifies rainfall along
the mountains and coastal areas. As a result, rainfall intensities and totals
in these areas increase. The effect of snow melt on flood runoff is significant
only in the few cases where warm spring rains from southerly storms fall on
a snow pack. Temperatures throughout the County usually remain above
freezing during major storms. Snow rarely falls on the coastal plain.
Snowfall at elevations above 5,000 feet frequently occurs during winter
28
storms. This snow melts rapidly except on the higher peaks and north
facing slopes. January and July are the coldest and warmest months of the
year, respectively. Seasonal temperature variations can be extreme across
the County. Record high temperatures of 112F (44.4C) have been
recorded in the Coastal Plain Area and a high of 99F (37.2C) has been
recorded at Mt. Wilson (5,700’msl) in the San Gabriel Mountains. Record
low temperatures have been recorded in these same areas of 28F (-2.2C)
and 9F (-12.7C) respectively.
2.1.5Desert Areas
Orographic precipitation over the mountains produces a rain shadow on the
leeward side of the mountains. As a result, the northern San Gabriel
Mountains and the Mojave Desert regions experience very low annual
precipitation amounts with rainfall occurring primarily during summer
convective rainfall associated with monsoonal flow from the south and
southwest. Flash flooding is possible in many of the desert areas as a result
of intense and localized rainfall from convective summer storms. Average
annual temperatures in the Mojave Desert range from a high of 91.4F
(33C) to a low of 62.9F (17.2C). Temperatures and precipitation can vary
wildly in all seasons across this region and a record high temperature of
134F (57C) a record low of 15F (-9C) have been recorded.
2.1.6Watersheds
For the purposes of their water resources management activities, the
County of Los Angeles, Department of Public Works (DPW) has defined
eight major watersheds and the LACounty subwatershed GIS data layer 1
divides the County’s watersheds into 2,655 subwatersheds. The sizes of
the subwatersheds range between 35 and 125,000 acres, with an average
of approximately 8,000 acres. Maps of the subwatersheds are available
from the Los Angeles County Geographic Information Systems (GIS) Data
Portal at http://dpw.lacounty.gov/general/spatiallibrary/site_options.cfm(LA
County subwatershed GIS data layer 1).
The locations and approximate boundaries of the major watersheds within
the County are shown on Figure 2-1. This information was downloaded
directly from the Los Angeles County GIS Data Portal. A description of the
major watersheds is provided below to help understand the hydrologic
conditions within each watershed.
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2.1.6.1 Santa Clara River
The Santa Clara River originates in the northern slopes of the San
Gabriel Mountains at PacificoMountain and travels west into Ventura
County, discharging into the Pacific Ocean near the City of Ventura.
The river runs approximately 100 miles from the headwaters near
Acton, California, to the ocean. The river drains an area of
approximately 1,600 square miles. The upper portion of the river,
within the County of Los Angeles, has a watershed area of
approximately 644 square miles. Ninety percent of this area is
mountainous with steep canyons; while the remaining ten percent is
alluvial valleys. The area is mostly undeveloped with a large portion
in the Angeles National Forest. There are some mixed-use
developed areas concentrated in or near the City of Santa Clarita.
The watershed is currently experiencing an accelerated rate of
development in areas adjacent to the river.
The Santa Clara River and its tributaries are ephemeral streams
characterized by alluvial soils. Discharge occurs quickly during
rainfall events and diminishes quickly after rainfall has ceased. As
in other county watersheds, the mountain and foothill areas are
susceptible to debris-laden flows during intense rainfall, especially
when a watershed is recovering from fire. The river remains in a
generally natural state with some modifications related to the
development of the floodplain. The expected population increase will
continue to produce floodplain encroachment, requiring additional
bank protection, channelization, and channel crossings. The
expected population increase, as well as increased imperviousness,
will impact the hydrologic characteristics of the river and the
sediment balance. Some of the major tributaries in the County’s
portion of the Santa Clara River watershed include: Castaic Creek,
San Francisquito Canyon, Bouquet Canyon, Sand Canyon, Mint
Canyon, and the South Fork of the Santa Clara River.
2.1.6.2 Los Angeles River
The Los Angeles River Watershed covers over 830 square miles.
The watershed includes the western portion of the San Gabriel
Mountains, the Santa Susana Mountains, the Verdugo Hills, and the
northern slope of the Santa Monica Mountains. The river flows from
the headwaters in the western San Fernando Valley and outlets in
31
San Pedro Bay near Long Beach. The river crosses the San
Fernando Valley and the central portion of the Los Angeles Basin.
The watershed terrain consists of mountains, foothills, valleys, and
the coastal plain.
The Los Angeles River and many of its tributaries have been the
subject of extensive engineering work to reduce the impacts of flood
events. Prior to development, the Los Angeles River system was
typical of other streams in the southwest. The river’s channel was
broad and often shifted location within the flood plain due to the high
sediment loads. The stream location within the coastal plain has
varied greatly overthe years. Between 1815 and 1825, the river
changed course completely. Breaking its banks in what is now
Downtown Los Angeles, the river followed the course of Ballona
Creek, reaching the ocean at a location 20 miles from its current
outlet.
th
Numerous flood control facilities were constructed in the early 20
century, as development began to take place on this wide flood plain.
The concrete sections of the Los Angeles River were constructed
between the late 1930’s and the 1950’s. Channel improvements and
extensive watershed development decrease times of concentration
and increase runoff flow rates and volumes. The Los Angeles
County Flood Control district constructed three major dams during
this period: Pacoima, Big Tujunga and Devil’s Gate. The dams were
built to reduce downstream flow rates and conserve water for ground
water recharge purposes. In the Rio Hondo drainage area, several
dams were constructed including Eaton Wash, Sierra Madre, Santa
Anita and Sawpit. Additionally, the U.S. Army Corps of Engineers
operates four major dams in the watershed to assist in flood control.
The four dams are Hansen, Lopez, Sepulveda and Whittier Narrows.
2.1.6.3 San Gabriel River
The San Gabriel River Watershed is located in the eastern portion of
the County. The river drains the San Gabriel Mountains to the north
and is bounded by the Los Angeles River Watershed and Santa Ana
River Watersheds. The watershed drains 640 square miles. The
Santa Gabriel River watershed outlets into the Pacific Ocean
between LongBeach and Seal Beach after passing through the
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Alamitos Bay estuary. Tributaries to the San Gabriel River include:
Walnut Creek, San Jose Creek, and Coyote Creek.
The upper portions of the watershed are contained almost entirely
within the Angeles National Forest and are nearly untouched by
development. The mountains in this area are extremely rugged with
steep V-shaped canyons. The vegetation is dominated by chaparral
and coastal sage scrub with patches of oak woodlands. Conifers are
dominant at higher elevations. The streambeds in the area contain
sycamore and alder woodlands.
In contrast, the lower part of the watershed is mostly developed
below the mouth of the San Gabriel Canyon. The developments
include commercial, residential, and industrial use. The developed
area in the San Gabriel Valley and Los Angeles Basin comprises
26% of the total watershed area.
Similar to the Los Angeles River, the San Gabriel River once
occupied a wide floodplain and shifted course to accommodate large
flows and sediment loads. Development of the floodplain required
changing the character of the river dramatically since periodic
inundation of the floodplain was not compatible with the new land
uses.
Several major dams and debris basins impound floodwaters and
prevent debris flows originating in the San Gabriel Mountains. These
include Cogswell Dam, San Gabriel Dam, Morris Dam, Big Dalton
Dam, San Dimas Dam, Live Oak Dam, and Thompson Creek Dam.
Many of these facilities were constructed in the 1930’s and have
proven their worth by preventing significant damage from large flood
events. Major flood events occurred in 1938, 1969, 1978, 1983,
1998, and 2005. Additionally, the U.S. Army Corps of Engineers
operates the Santa Fe Dam and Whittier Narrows Dam in the
watershedto assist in flood control.
The San Gabriel River has been channelized below Santa Fe Dam
to aid in flood prevention. However, the channel invert was left
unlined for much of its length between Santa Fe Dam and Florence
Avenue in Downey. The unlined bottom promotes infiltration of flood
waters released from upstream dams. Public Works installed rubber
dams to further utilize the river bottom for ground water recharge.
The most significant spreading ground facilities in the County are
33
located in the SanGabriel River watershed. Runoff resulting from
storm events is diverted into the spreading facilities and allowed to
recharge groundwater. Major spreading grounds are located at the
mouth of San Gabriel Canyon and in the Montebello area
downstream of theWhittier Narrows Dam.
2.1.6.4 Antelope-Fremont Valleys
Although the Antelope Valley and Fremont Valley Watersheds are
separated by a topographic and hydrologic divide in the Antelope
Valley, they are often referred to collectively as the Antelope-
Fremont Valleys watershed.
The Antelope Valley Watershed is a large, closed basin in the
western Mojave Desert. This watershed straddles the Los Angeles-
Kern County line and drains a total of 3,387 square miles.
Approximately 80 percent of the watershed is characterized by a low
to moderate slope (0-7 percent). The remaining 20 percent consists
of foothills and rugged mountains, some of which reach up to 3,600
feet in elevation. The floor of the Antelope Valley Watershed
generally lacks defined natural channelsoutside of the foothills and
is subsequently subject to unpredictable sheet flow patterns. The
Antelope Valley Watershed is a closed basin with no outlets to the
ocean. All water that enters the watershed either infiltrates into the
underlying groundwater basin, or flows toward three playa lakes
located near the center of the watershed.
A playa lake is formed when rain fills a playa, or small, round
depression in the surface of the ground. Playa lakes are usually
endorheic, which means they have no outflow of water. The playa
lakes in the Antelope Valley Watershed are all located on Edwards
Air Force Base. They include the following: Rosamond Lake, which
covers approximately 21 square miles; Rogers Dry Lake, which is
located east of Rosamond Lake and encompasses approximately 32
square miles; and Buckhorn Dry Lake, which is located between
Rosamond and Rogers Dry Lake, encompassing three square miles.
These playa lakes are usually dry, and they only receive water
following large winter storms. Surface runoff that collects in the dry
lakes quickly evaporates from the surface, and only a small quantity
of water infiltrates to the groundwater due to the nearly impermeable
nature of the playa soils.
34
The Fremont Valley Watershed receives surface water runofffrom
Lone Tree Canyon, Cache Creek, and other ridges adjacent to the
area. Throughout most of this watershed surface water drains
toward Koehn Lake, which is a generally dry lake about 20 miles
northeast of the community of Mojave. In the southwestern portion
of the Fremont Valley Watershed, surface water runoff flows south
towards Rosamond. The Antelope Valley Watershed receives
surface water runoff from the San Gabriel Mountains and the
Tehachapi Mountains, including Big Rock Creek, Littlerock Creek,
Oak Creek, and Cottonwood Creek. There are multiple intermittent
or ephemeral waterways in the area which convey surface water
runoff to Rosamond Lake during extreme rain events. Rosamond
Lake, which is located on Edwards Air Force Base northeast of
Lancaster, remains dry most of the year.
Within the Los Angeles County portion of the Antelope Valley, the
County Sanitation Districts of Los Angeles County operate sewage
treatment plants for portions of the Cities of Lancaster and Palmdale.
Sewage disposal needs for the remainder of Los Angeles County in
this watershed are by OWTS.
2.1.6.5 Santa Monica Bay
The Santa Monica Bay or Coastal watershed is comprised of a
number of individual watersheds that outlet into Santa Monica and
San Pedro Bays. These include the major watersheds of Malibu
Creek, Topanga Creek, Ballona Creek, and the Dominguez Channel.
These watersheds have unique topographic and hydrologic
characteristics ranging from undeveloped to highly urbanized. For
simplicity, these coastal watersheds are grouped together due to
their relatively small sizes.
The Malibu Creek Watershed is comprised of 109 square miles at
the western end of the County of Los Angeles and extends into
Ventura County. Most of the watershed is undeveloped public land.
There is sporadic but increasing development throughout the area.
The most extensive development is centered along US Highway 101.
The northern portion is hilly while the southern portion, near the
ocean, is rugged mountain terrain. Malibu Creek drains into the
Pacific Ocean near the Malibu Civic Center.
35
Topanga Creek drains 18 square miles in the centralSanta Monica
Mountains. The watershed is primarily rural with widely scattered
residential and commercial development. The creek flows
unobstructed along its course and empties into the Santa Monica
Bay in an unincorporated portion of the County east ofMalibu.
Ballona Creek is a flood control channel that drains the western Los
Angeles basin. The watershed area is bounded by the Santa Monica
Mountains on the north and the Baldwin Hills on the south. It extends
east nearly to downtown Los Angeles. Thetotal watershed area is
roughly 130 square miles. The area is primarily developed but
includes undeveloped areas on the south slope of the Santa Monica
Mountains. The land use is 64% residential, 8% commercial, 4%
industrial, and 17% open space. The major tributaries to Ballona
Creek include: Centinela Creek, Sepulveda Canyon Channel,
Benedict Canyon Channel, and numerous storm drains. The
watershed drains into Santa Monica Bay at Marina del Rey.
2.1.6.6 Santa Ana
Los Angeles County encompasses a relatively thin sliver of the Santa
Ana Watershed located in the northeastern portion of the County.
The Santa Ana watershed covers an area of about 2,700 square
miles in parts of Orange, San Bernardino, Riverside, and Los
Angeles Counties. The Santa Ana Basin is substantially urbanized:
about 32 percent of the land use is residential, commercial, or
industrial, and the area is home to more than 4 million people.
Agricultural land use accounts for about 10 percent of the watershed.
The Santa Ana River is the largest stream system in southern
California, beginning in the San Bernardino Mountains, which reach
altitudes exceeding 10,000 feet, and flowing more than 100 miles to
the Pacific Ocean near Huntington Beach. The San Jacinto River is
a tributary of the Santa Ana River, but it normally terminates in
Riverside County at Lake Elsinore.
Most of the precipitation in the watershed occurs between November
and March. Consequently, under natural conditions, the Santa Ana
River would be intermittent with littleor no flow in the summer
months.
36
Ground water is the main source of water supply in the watershed,
providing about 66 percent of the consumptive water demand. Inland
aquifers, upstream from Prado Dam, underlie about 1,200 square
miles of the watershed. Coastal aquifers, downstream from Prado
Dam, underlie about 400 square miles. Thickness of these aquifers
ranges from several hundred to more than 1,000 feet. Depth to
ground water ranges from several hundred feet near the flanks of
mountains to near land surface along rivers and wetlands, and in the
coastal plain.
Enhanced recharge of ground water is an important component of
the hydrologic cycle in the Santa Ana watershed. The volume of
water recharged is 37 percent of the volume pumped, with most of
the enhanced recharge consisting of surface water derived from
precipitation within the basin. Discharge from wastewater treatment
facilities is also an important component of the hydrologic cycle,
providing base flow in many parts of the drainage network.These
activities are among the many factors affecting water quality in the
watershed.
2.1.6.7 Mojave
The Mojave Watershed encroaches into Los Angeles County at
several relatively small sections along the northeastern county line
between San Bernardino and Los Angeles Counties. The Mojave
Watershed encompasses approximately 4,500 square miles in total
and is located almost entirely within San Bernardino County. Total
population in the watershed is increasing every year and was nearly
one-half million by the end of year 2015. Much of the existing and
projected future population is concentrated in the Victor Valley, which
includes the incorporated cities of Victorville, Hesperia, Apple Valley,
and Adelanto.
The primary geographic and hydrologic feature of the watershed is
the Mojave River. The headwaters of the Mojave River are in the
San Bernardino Mountains, which annually receives greater than 40
inches of precipitation at its highest elevations. Much of the winter
precipitation in the San BernardinoMountains falls in the form of
snow that provides spring recharge to the Mojave River system.
Historically, the annual recharge from the headwaters is
approximately 75,000 acre-feet. The Mojave River channel, through
37
both surface and subsurface flow, transects the watershed a linear
distance of approximately 120 miles to its terminus at Silver Dry Lake
near the Community of Baker. Aside from intense storm events, the
Mojave River channel is typically dry downstream of the Mojave
Forks Dam except in select locations where ground water is forced
to the surface by geologic structures.
The Mojave River has been selected as a priority or “focus”
watershed because of numerous water quality and quantity issues.
Historically known for its agricultural, industrial and military land
uses, the Victor Valley has significantly changed during the last
several decades into a satellite of Southern California’s urbanization.
Urban growth has significantly modified the arena of waste
discharges that could potentially affect water quality, including
stormwater and wastewater treatment. There are also numerous
water quality issues associated with past and current agricultural,
industrial, and military land uses throughout the watershed. Because
of water quality degradation associated with past industrial activities,
some waters in the Mojave River watershed are listed as a water
quality limited segments for priority organics on the federal Section
303(d) list of impaired water bodies.
Typical of southwestern arid environments, the Mojave Watershed
has limited water resources. Surface water from the headwaters in
the San Bernardino Mountains quickly percolates into the porous
sands of the young Mojave River alluvium. Thus, ground water is
the primary source of water supplyin most of the watershed. In a
constant state of overdraft since the 1950’s, the ground water
resources of the Mojave Watershed were formally adjudicated in
1996 through a stipulated judgment. The stipulated judgment was
appealed shortly thereafter. The California Supreme Court issued a
decision in the case on August 22, 2000 that affirmed water rights
priority in cases of competing water apportionment.
2.1.6.8 Calleguas
A very small portion of the Calleguas Creek watershed is located at
the very western edge of Los Angeles County. The entire Calleguas
watershed encompasses approximately 343 square miles the
majority of which lies within Ventura County California. This greater
watershed is made of up 7 sub-watersheds at the 12 digit HUC
38
(hydrologic unit code) scale. Undeveloped areas account for 50% of
the land in the greater watershed while 25% is urban, and 25% is
agricultural. Most of the urban areas, including the communities of
Moorpark, Simi Valley and Thousand Oaks are located in the upper
sub-watershed and most of the agriculture is located in the middle
and lower sub-watersheds. The portion that lies within Los Angeles
County is located in the mountainous area just west of the Santa
Clarita Valley.
2.1.6.9 Middle Kern-Upper Tehachapi-Grapevine
The Middle Kern-Upper Tehachapi-Grapevine Watershed
encroaches slightly into the boundaries of Los Angeles County at the
very northwestern corner of the County near the town of Gorman.
Specifically, the portion of the watershed that includes the Castaic
Lake Valley Groundwater Basin (5-29) member of the Tulare Lake
Hydrologic Region.
Erosion along the Garlock Fault is responsible for forming the basin’s
northeast and southwest arms. Castaic Lake represents a structural
depression or sag pond developed onthe Garlock Fault (DWR
1965). A geologic map of the area of Castaic Lake area depicts the
geology as Quaternary playa deposits of recent age, consisting of
silt, clay and sandy clay. The remainder of the basin is mapped as
younger alluvium with small areas of older alluvium at the basin
margins. Very little data is available for the basin. Of the two
available well completion reports for wells near Castaic Lake in the
northeast arm of the basin, both intercept bedrock of the Garlock
Fault Zone at depths of 50 feet or less –both produced less than 3
gpm and were destroyed after drilling. The near surface material in
these wells was silty sand, clayey sands, and sandy clays.
Irrigation and municipal supply wells in the basin’s west side and
north arm, near the center of the basin fill, are capable of producing
over 200 gpm. One log for an irrigation well in the northern arm of
the basin suggested artesian conditions were encountered after
completion.
2.2 Groundwater
Groundwater resources in Los Angeles County are managed and utilized by
39
literally hundreds of different agencies and integrated management groups across
the geographic area. Within the Los Angeles basin itself, the Central Basin and
the West Coast Basin (Figure 2-2) provide 40 percent of the water used by almost
4 million people living in the 43 cities that overlie these two basins alone. For the
purpose of this LAMP Figure 2-2identifies eighteen separate groundwater basins
within Los Angeles County. Many of these basins have numerous sub-basins
identified within them that are defined by various geologic or hydrogeologic
boundary conditions. The following is a description of the hydrology, groundwater
quality, and impairments for the nine major groundwater basins shown on Figure
2-2.
2.2.1Antelope Valley (6-44)
Description–Antelope Valley Groundwater Basin underlies an extensive
alluvial valley in the western Mojave Desert. The elevation of the valley
floor ranges from 2,300 to 3,500 feet above sea level. The basin is bounded
on the northwest by the Garlock fault zone at the base of the Tehachapi
Mountains and on the southwest by the San Andreas fault zone at the base
of the San Gabriel Mountains. The basin is bounded on the east by ridges,
buttes, and low hills that form a surface and groundwater drainage divide
and on the north by Fremont Valley Groundwater Basin at a groundwater
divide approximated by a southeastward-trending line from the mouth of
Oak Creek through Middle Butte to exposed bedrocknear Gem Hill, and by
the Rand Mountains farther east.
Runoff in Big Rock and Little Rock Creeks from the San Gabriel Mountains
and in Cottonwood Creek from the Tehachapi Mountains flows toward a
closed basin at Rosamond Lake (Jennings and Strand 1969). Rogers Lake
is a closed basin in the northern part of Antelope Valley that collects
ephemeral runoff from surrounding hills (Rogers 1967). Average annual
rainfall ranges from 5 to 10 inches.
Groundwater Quality -Groundwater quality is excellent within the upper or
“principal” aquifer but degrades toward thenorthern portion of the dry lake
areas. Considered to be generally suitable for domestic,agricultural, and
industrial uses, the water in the principal aquifer has a total dissolved solids
(TDS) concentration ranging from 200 to 800 milligrams per liter (mg/L). The
deeper aquifers typically have higher TDS levels. Hardness levels range
from 50 to 200 mg/L and high fluoride, boron, and nitrate concentrations
have been measured in some areas of the basin. Arsenic is a concern in
parts of the region and has been observed in some water supply wells.
40
Research conducted by Waterworks and USGS has shown the problem to
reside primarily in the deep aquifer. It is not anticipated that the existing
arsenic concentrations will lead to future loss of groundwater as a water
supply resource for the region. Portions of the basin have experienced
nitrate levels above the maximum contaminant level (MCL) of 10 mg/L as
N. Most, if not all, water supply wells in the Antelope Valley draw
groundwater from the principal aquifer. The SNMP and future monitoring
plan will focus on the groundwater quality in the principal aquifer(Antelope
Valley SNMP 2014).
The overall basin concentration of eachconstituent meets the SNMP water
quality management goals. Compared to the other sub-basins,North Muroc
and Peerless generally have higher concentrations of TDS, chloride,
chromium,fluoride, and boron. This is not a concern, however, as the
concentrations for these constituentsmeet all drinking water regulations. As
discussed in the previous section, these constituents arenaturally occurring
(Antelope Valley SNMP 2014).
Impairments–Arsenic is a concern in the Antelope Valley. The elevated
arsenic concentrations in the Gloster,Neenach, North Muroc, Peerless, and
Willow Springs sub-basins exceed the regulatory drinkingwater and SNMP
water quality management goals. High arsenic in groundwater is naturally
occurring, resulting from dissolution of rocks and minerals. Arsenic
concentrations above the MCLpotable
applications. Wells with concentrations above the MCL aretypically treated
to remove arsenic, blended to dilute arsenic concentration, or shut down
(Antelope Valley SNMP 2014).
2.2.2Acton Valley (4-05)
Description–The Acton Valley Groundwater Basin is bounded by the Sierra
Pelona on the north and the San Gabriel Mountains on the south, east, and
west. The valley is drained by the Santa Clara River. Average annual
precipitation ranges from 10 to16 inches.
Water Quality–Groundwater in the basin is generally calcium bicarbonate
in character. However, in the broad valley north of Acton, 2 wells have
calcium-magnesium sulfate character and 9 wells have calcium magnesium
bicarbonate character (Slade 1990). Water sampled from 5 public supply
wells in the basin show an average TDS content of approximately 579 mg/L
41
and a range of 424 to 712 mg/L. TDS content ranged from 279 to 480 mg/L
during June 1988 through July 1989 (Slade 1990).
Impairments–Water sampled from 75 wells measured during 1989 show
high concentrations of TDS, sulfate, and chloride in the northern part of the
basin with some of these concentrations exceeding drinking water
standards (Slade 1990; DWR 1993). The water from two wells in the basin
have nitrate concentrations that exceed drinking water standards (DWR
1968).
2.2.3Santa Clara River Valley East (4-04.07)
Description–The Santa Clara River Valley East Subbasin is bordered on
the north by the PiruMountains, on the west by impervious rocks of the
Modelo and Saugus Formations and a constriction in the alluvium (DPW
1933), on the south by the Santa Susana Mountains, and on the south and
east by the Gabriel Mountains. The surface is drained by the Santa Clara
River, Bouquet Creek, and Castaic Creek. Average annual precipitation
ranges from 14 to 16 inches.
Water Quality–Groundwater in the alluvial aquifer varies from calcium
bicarbonate character in the east to calcium sulfate character in the western
part of the subbasin (Slade 2002). Nitrate content decreases to the west
and TDS content increases from about 550 to 600 mg/L in the east to about
1,000 mg/L in the west (Slade 2002). Groundwater in the Saugus
Formation aquifer is of calcium bicarbonate character in the southeast,
calcium sulfate in the central, and sodium bicarbonate in the western parts
of the subbasin (Slade 2002). TDS content in the Saugus Formation aquifer
ranges from about 500 to 900 mg/L (Slade 2002). Water sampled from 59
public supply wells show an average TDS content of 695 mg/L in the
subbasin and a range from 300 to 1,662 mg/L.
Impairments–Nitrate content has exceeded 45 mg/L in some parts of the
subbasin with a well in the central part of the subbasin reaching 68 mg/L
(DWR 1968; 1977). TDS content may also be elevated, particularly in the
western part of the subbasin to become unsuitable for domestic use (DWR
1968; 1979). Trichloroethylene and ammonium perchlorate have been
detected in four wells in the eastern part ofthe subbasin (Slade 2002).
42
2.2.4San Fernando Valley (14-12)
Description–The San Fernando Valley Groundwater Basin was
adjudicated in 1979 and includes the water-bearing sediments beneath the
San Fernando Valley, Tujunga Valley, Browns Canyon, and the alluvial
areas surrounding the Verdugo Mountains near La Crescenta and Eagle
Rock. The basin is bounded on the north and northwest by the Santa
Susana Mountains, on the north and northeast by the San Gabriel
Mountains, on the east by the San Rafael Hills, on the south by the Santa
Monica Mountains and Chalk Hills, and on the west by the Simi Hills. The
valley is drained by the Los Angeles River and its tributaries. Precipitation
in the San Fernando Valley ranges from 15 to 23 inches per year and
averages about 17 inches.
Water Quality–In the western part of basin, calcium sulfate-bicarbonate
character is dominant, and in the eastern part of basin, calcium bicarbonate
character dominates (ULARAW 1999). Total dissolve solids range from 326
to 615 mg/L, and electrical conductivity rang
(ULARAW 1999). Data from 125 public supply wells shows an average
TDS content of 499 and a range from 176 to 1,160.
Impairments–A number of investigations have determined contamination
of volatile organic compounds such as trichloroethylene (TCE),
perchloroethylene (PCE), petroleum compounds, chloroform, nitrate,
sulfate, and heavy metals (Setmire 1985; ULARAW 1999). TCE, PCE and
nitrate contamination occurs in the eastern part of the basin and elevated
sulfate concentration occurs in the western part of the basin (ULARAW
1999).
2.2.5Raymond (4-23)
Description–The Raymond Basin is located in the northwest part of the
San Gabriel Valley, in eastern Los Angeles County, and was considered a
part of the San Gabriel Valley Groundwater Basin (4-13) in Bulletin 118-75
and Bulletin 118-80. The Raymond Basin includes the water-bearing
sediments bounded by the contact with consolidated basement rocks of the
San Gabriel Mountains on the north and the San Rafael Hills on the
southwest. The west boundary is delineated by a drainage divide at
Pickens Canyon Wash and the southeast boundary is the Raymond fault.
Precipitation averages in the basin range from about 19 inches in valley to
43
25 inches in upland areas. The average precipitation over the basin is about
21 inches.
Water Quality–Groundwater in this basin is typically calcium bicarbonate
in character. The average total dissolved solids content in the Hydrologic
Region South Coast California’s Groundwater Raymond Groundwater
Basin Bulletin 118 last update 2/27/04. Pasadena portion of the basin is
about 400 mg/L, with a high of 600 mg/L (PWP 2000). The Electrical
2000). Data for 70 public supply wells indicate an average TDS content of
346 mg/L with a range from 138 to 780 mg/L.
Impairments–Fluoride content occasionally exceeds recommended levels
of 1.6 mg/L, near the San Gabriel Mountain front (maximum of 3.1 mg/L;
average of 1.0 mg/L; \[DWR 1978\]). High nitrate concentrations are found
in water from some wells near Pasadena (RBMB 1999). Volatile organic
compounds are detected in wells near Arroyo Seco (RBMB 1999).
Radiation is occasionally detected near the San Gabriel Mountains (DWR
1978). A Superfund site exists near the Jet Propulsion Laboratories
because of Perchlorate contamination (RBMB 1999).
2.2.6San Gabriel Valley (4-13)
Description–The San Gabriel Valley Groundwater Basin is located in
eastern Los Angeles County and includes the water-bearing sediments
underlying most of the San Gabriel Valley andincludes a portion of the
upper Santa Ana Valley that lies in Los Angeles County. This basin is
bounded on the north by the Raymond fault and the contact between
Quaternary sediments and consolidated basement rocks of the San Gabriel
Mountains. Exposed consolidated rocks of the Repetto, Merced, and
Puente Hills bound the basin on the south and west, and the Chino fault
and the San Jose fault form the eastern boundary (DWR 1966). The Rio
Hondo and San Gabriel drainages have their headwaters in the San Gabriel
Mountains, then surface water flows southwest across the San Gabriel
Valley and exit through the Whittier Narrows, a gap between the Merced
and Puente Hills. Precipitation in the basin ranges from 15 to 31 inches,
and averages around 19 inches.
Water Quality–Water within the basin is primarily calcium bicarbonate in
character. In the north, west and central regions of the basin, TDS ranges
from 90 to 4,288 mg/l and averages around 367 mg/l (DWR unpublished
44
data). In the southern portion of the basin the TDS averages around 1,222
mg/l (PBWM 1999). TDS content ranges from 500 to 1,500 mg/l in the
eastern part of the basin (Smith 2000), and from 200 to 500 mg/L in the
northeast part (JMM 1985). Data from 259 public supply wells shows an
average TDS content of 318 mg/L and a range of 172 to 914 mg/L.
Impairments–Four areas of the San Gabriel Valley Groundwater Basin are
Superfund Sites. Trichloroethylene, Perchloroethylene, and Carbon
Tetrachloride contaminate the Whittier Narrows, Puente basin, Baldwin
Park and El Monte areas (DWR 1998).
Within the Six Basins Area there exists high levels of nitrates in the
northeastern part of the Pomona Basin, and a plume of volatile organic
compounds occupies the southern portion of Pomona Basin (SBWM 2000).
ThePuente Basin has numerous sites where clean-up operations are in
affect. There is an EPA assigned Superfund Site, the Puente Valley
Operable Unit, which is cleaning up plumes of TCE and PCE (EPA 1998).
2.2.7Coastal Plain ofLos Angeles Santa Monica (4-11.01)
Description–The Santa Monica Subbasin underlies the northwestern part
of the Coastal Plain of Los Angeles Groundwater Basin. It is bounded by
impermeable rocks of the Santa Monica Mountains on the north and by the
Ballona escarpment on the south. The subbasin extends from the Pacific
Ocean on the west to the Inglewood fault on the east. Ballona Creek is the
dominant hydrologic feature and drains surface waters to the Pacific Ocean.
Water Quality–Analyses of water from 7 public supply wells indicate an
average TDS content of 916 mg/L and a range of 729 to 1,156 mg/L.
Impairments–None known.
2.2.8Coastal Plain of Los Angeles West-Coast (4-11.03)
Description–The West Coast Subbasin of the Coastal Plain of Los Angeles
Basin is adjudicated and commonly referred to as the “West Coast Basin.”
It is bounded on the north by the Ballona Escarpment, an abandoned
erosional channel from the Los Angeles River. On the east it is bounded by
the Newport-Inglewood fault zone, and on the south and west by the Pacific
Ocean and consolidated rocks of the Palos Verdes Hills (DWR 1999). The
surface of the subbasin is crossed in the south by the Los Angeles River
through the Dominguez Gap, and the San Gabriel River through the
45
Alamitos Gap, both of which then flow into San Pedro Bay. Average
precipitation throughout the subbasin is 12 to 14 inches.
Water Quality–The character of water in the Gaspur zone of the subbasin
is variable. Seawater intrusion has produced deterioration of water quality
over time. Early tests indicated that the water was sodium bicarbonate in
character. It is questionable whether this is representative of the entire
zone, because the higher quality water residing outside the subbasin is
calcium bicarbonate in nature (DPW 1952).
The Gardena water-bearing zone exhibits a calcium-sodium bicarbonate
character and is of good quality. In the Silverado zone, the character of
water varies considerably. In the coastal region of this zone, the water is
calcium chloride in character, and then transitions into sodium bicarbonate
moving inland. The Pico formation is sodium bicarbonate in nature and is
of good quality (DPW 1952). Data from 45 public supply wells shows an
average TDS content of 720 mg/L and a range of 170 to 5,510 mg/L.
Impairments–Seawater intrusion occurs in the Silverado zone along the
Santa Monica Bay and in the Gaspur zone in the San Pedro Bay. Two
seawater barrier projects are currently in operation. The West Coast Basin
Barrier Project, which runs from the Los Angeles Airport to the Palos Verde
Hills, and the Dominguez Gap Barrier Project which covers the area of the
West Coast Basin bordering the San Pedro Bay. Injection wells along these
barriers create a groundwater ridge, which inhibits the inland flow of salt
water into the subbasin to protect and maintain groundwater elevations
(DWR 1999).
2.2.9Coastal Plain of Los Angeles Central (4-11.04)
Description–The Central Subbasin occupies a large portion of the
southeastern part of the Coastal Plain of Los Angeles Groundwater Basin.
This subbasin is commonly referred to as the “Central Basin” and is
bounded on the north by a surface divide called the La Brea high, and on
the northeast and east by emergent less permeable Tertiary rocks of the
Elysian, Repetto, Merced and Puente Hills. The southeast boundary
between Central Basin and Orange County Groundwater Basin roughly
follows Coyote Creek, which is a regional drainage province boundary. The
southwest boundary is formed by the Newport Inglewood fault system and
the associated folded rocks of the Newport Inglewood uplift. The Los
Angeles and San Gabriel Rivers drain inland basins and pass across the
46
surface of the Central Basin on their way to the Pacific Ocean. Average
precipitation throughout the subbasin ranges from 11 to 13 inches with an
average of around 12 inches.
Water Quality–TDS content in the subbasin ranges from 200 to 2,500 mg/l
according to data from 293 public supply wells. The average for these 293
wells is 453 mg/l.
Impairments–None known
47
2.3 Geologic Factors, OWTS Suitability and Soils
Geologic Factors and OWTS Suitability
Geology is crucial to the suitability and performance of OWTS due to its influence
on topography and landforms, the type and characteristics of soils that develop at
the surface, the occurrence and movement of sub-surface water, and slope
stability. Geologic conditions are typically of greater significance in the
mountainous regions, where the rock formations may influence the suitability for
and effects of OWTS in areas with relatively thin or poorly developed soils, and or
relatively shallow groundwater.
Geologic factors are addressed for new OWTS based on:
Information from the basic site evaluations for all installations;
For dispersal systems located on natural slopes over 30%, information from the
slope evaluation;
For unstable land masses or areassubject to earth slides, information from the
geotechnical study, including assessment of hydrogeologic conditions, water
movement and slope evaluation.
Soil Conditions
Soil suitability is the single most critical aspect of onsite wastewater treatment and
dispersal. The soil provides the medium for the absorption and treatment of
wastewater discharged through sub-surface dispersal systems. This is
accomplished mainly through a combination of physical filtering, biological and
chemical processes, and dilution. Protection of underlying groundwater relies on
provision of an adequate depth of permeable soil below the dispersal field (zone
of aeration) for absorption and treatment to occur. The Requirements and
Procedures for Conventional and Non-Conventional Onsite Wastewater Treatment
Systems (DPH, 2016) requires detailed site evaluation to document suitable soil
characteristics and depth for each new OWTS installation consistent with industry
practices and appropriate for the conditions and requirements inLos Angeles
County (See Section 3). The observed depth and engineering characteristics of
the soil are used to select the appropriate location, sizing and design of the OWTS
to achieve proper effluent dispersal and groundwater protection.
Soil Mapping and Soil Hydrologic Groups
49
Los Angeles County has a complex geology and mapping of individual soil types
and associated soil engineering properties is not practical at the scale of the
individual project site. However, for informational purposes, soils that share certain
characteristics can be grouped and shown at a county-wide scale as map units
(Figure 2.3). A map unit is a collection of areas defined and named the same in
terms of their soil components or miscellaneous areas or both (NSSH 627.03).
Soilscientists assign map unit components to hydrologic soil groups. Map unit
components assigned to a specific hydrologic soil group have similar physical and
runoff characteristics. Soils in the United States, its territories, and Puerto Rico
have been assigned to hydrologic soil groups. The assigned groups can be found
by consulting soils information published by the Natural Resources Conservation
Services (NRCS, 2016).
Soils were originally assigned to hydrologic soil groups based on measured
rainfall, runoff, and infiltrometer data (Musgrave, 1955). Since the initial work was
done to establish these groupings, assignment of soils to hydrologic soil groups
has been based on the judgment of soil scientists. Assignments are made based
on comparison of the characteristics of unclassified soil profiles with profiles of
soils already placed into hydrologic soil groups. Most of the groupings are based
on the premise that soils found within a climatic region that are similar in depth to
a restrictive layer or water table, transmission rate of water, texture, structure, and
degree of swelling when saturated, will have similar runoff responses. The classes
are based on the following factors:
Intake and transmission of water under the conditions of maximum yearly
wetness (thoroughly wet);
Soil not frozen;
Bare surface soil; and
Maximum swelling of expansive clays.
The slope of the soil surface is not considered when assigning hydrologic soil
groups. In its simplest form, hydrologic soil group is determined bythe water
transmitting soil layer with the lowest saturated hydraulic conductivity and depth to
any layer that is more or less water impermeable (such as a fragipan or duripan)
or depth to a water table (if present). The least transmissive layer can be any soil
horizon that transmits water at a slower rate relative to those horizons above or
below it. For example, a layer having a saturated hydraulic conductivity of 9.0
micrometers per second (1.3 inches per hour) is the least transmissive layer in a
soil if the layers above and below it have a saturated hydraulic conductivity of 23
micrometers per second (3.3 inches per hour). Water impermeable soil layers are
50
among those types of layers recorded in the component restriction table of the
National Soil Information System (NASIS) database. The saturated hydraulic
conductivity of an impermeable or nearly impermeable layer may range from
essentially 0 micrometers per second (0 inches per hour) to 0.9 micrometers per
second (0.1 inches per hour). For simplicity, either case is considered
impermeable for hydrologic soil group purposes. In some cases, saturated
hydraulic conductivity (a quantitatively measured characteristic) data are not
always readily available or obtainable. In these situations, other soil properties
such as texture, compaction (bulk density), strength of soil structure, clay
mineralogy, and organic matter are used to estimate water movement.
The four hydrologic soil groups (HSGs) are described as (Figure 2.3):
Group A —Soils in this group have low runoff potential when thoroughly wet.
Water is transmitted freely through the soil. Group A soils typically have less than
10 percent clay and more than 90 percent sand or gravel and have gravel or sand
textures. Some soils having loamy sand, sandy loam, loam or silt loam textures
may be placed in this group if they are well aggregated, of low bulk density, or
contain greater than 35 percent rock fragments.
The limits on the diagnostic physical characteristics of group A are as follows. The
saturated hydraulic conductivity of all soil layers exceeds 40.0 micrometers per
second (5.67 inches per hour). The depth to any water impermeable layer is
greater than 50 centimeters \[20 inches\]. The depth to the water table is greater
than 60 centimeters \[24 inches\]. Soils that are deeper than 100 centimeters \[40
inches\] to a water impermeable layer and a water table are in group A if the
saturated hydraulic conductivity of all soil layers within 100 centimeters \[40 inches\]
of the surface exceeds 10 micrometers per second (1.42 inches per hour).
Group B —Soils in this group have moderately low runoff potential when
thoroughly wet. Water transmission through the soil is unimpeded. Group B soils
typically have between 10 percent and 20 percent clay and 50 percent to 90
percent sand and have loamy sand or sandy loam textures. Some soils having
loam, silt loam, silt, or sandy clay loam textures may be placed in this group if they
are well aggregated, of low bulk density, or contain greater than 35 percent rock
fragments.
The limits on the diagnostic physical characteristics of group B soils are as follows.
The saturated hydraulic conductivity in the least transmissive layer between the
surface and 50 centimeters \[20 inches\] ranges from 10.0 micrometersper second
(1.42 inches per hour) to 40.0 micrometers per second (5.67 inches per hour). The
51
depth to any water impermeable layer is greater than 50 centimeters \[20 inches\].
The depth to the water table is greater than 60 centimeters \[24 inches\]. Soils that
are deeper than 100 centimeters \[40 inches\] to a water impermeable layer and a
water table are in group B if the saturated hydraulic conductivity of all soil layers
within 100 centimeters \[40 inches\] of the surface exceeds 4.0 micrometers per
second (0.57 inches per hour) but is less than 10.0 micrometers per second (1.42
inches per hour).
Group C—Soils in this group have moderately high runoff potential when
thoroughly wet. Water transmission through the soil is somewhat restricted.
Group C soils typically have between 20 percent and 40 percent clay and less than
50 percent sand and have loam, silt loam, sandy clay loam, clay loam, and silty
clay loam textures. Some soils having clay, silty clay, or sandy clay textures may
be placed in this group if they are well aggregated, of low bulk density, or contain
greater than 35 percent rock fragments.
The limits on the diagnostic physical characteristics of group C are as follows. The
saturated hydraulic conductivity in the least transmissive layer between the surface
and 50 centimeters \[20 inches\] is between 1.0 micrometers per second (0.14
inches per hour) and 10.0 micrometers per second (1.42 inches per hour). The
depth to any water impermeable layer is greater than 50 centimeters \[20 inches\].
The depth to the water table is greater than 60 centimeters \[24 inches\]. Soils that
are deeper than 100 centimeters \[40 inches\] to a restriction and a water table are
in group C if the saturated hydraulic conductivity of all soil layers within 100
centimeters \[40 inches\] of the surface exceeds 0.40 micrometers per second (0.06
inches per hour) but is less than 4.0 micrometers per second (0.57 inches per
hour).
Group D—Soils in this group have high runoff potential when thoroughly wet.
Water movement through the soil is restricted or very restricted. Group D soils
typically have greater than 40 percent clay, less than 50 percent sand, and have
clayey textures. In some areas, they also have high shrink-swell potential. All soils
with a depth to a water impermeable layer less than 50 centimeters \[20 inches\]
and all soils with a water table within 60 centimeters \[24 inches\] of the surface are
in this group, although some may have a dual classification, as described in the
next section, if they can be adequately drained.
The limits on the physical diagnostic characteristics of group D are as follows. For
soils with a water impermeable layer at a depth between 50 centimeters and 100
centimeters \[20 and 40 inches\], the saturated hydraulic conductivity in the least
transmissive soil layer is less than or equal to 1.0 micrometers per second (0.14
52
inches per hour). For soils that are deeper than 100 centimeters \[40 inches\] to a
restriction or water table, the saturated hydraulic conductivity of all soil layers within
100 centimeters \[40 inches\] of the surface is less than or equal to 0.40 micrometers
per second (0.06 inches per hour).
As a result of construction and other disturbances, the soil profile can be altered
from its natural state and the listed group assignments generally no longer apply,
nor can any supposition based on the natural soil be made that will accurately
describe the hydrologic properties of the disturbed soil. In these circumstances,
an onsite investigation should be made to determine the hydrologic soil group. The
information provided in Figure 2-3 is provided as a general assessment tool and is
not a substitute for site-specific investigation of and planning for OWTS. It provides
a general indication of the management and design issues likely to be encountered
in each area. It does not take into account local variations in soil types and is not
intended to be used for engineering or design purposes.
53
2.4 OWTS Usage Estimates
The DPH maintains a comprehensive inventory of existing OWTS usage in Los
Angeles County. As of January 28 2016, 53,148 OWTS and 813 NOWTS were
listed in the inventory. The estimate includes all OWTS within the County’s
jurisdiction.
OWTS are used almost exclusively on properties located outside of municipal
sewer service boundaries, which primarily includes large areas in the northern and
northeastern portions of the County, as well as in the mountain regions. The
portions of the County served by OWTS include: (a) unincorporated areas of Los
Angeles County; (b) cities that contract with the County for Building and Safety
approval; and (c) any city that enters into an agreement with the County for OWTS
management pertaining to the LAMP. Currently, eleven (11) cities have entered
into agreements with DPH for management of OWTS, including, Agoura Hills,
Bradbury, La Canada-Flintridge, La Habra Heights, Lynwood, Palos Verdes
Estates, Rolling Hills, Rolling Hills Estates, Lancaster, Palmdale and Walnut.
Figure 2-4provides a map of average annual precipitation in these geographic
areas.
To assist with present and future management of OWTS and water quality
assessments, Figure 2-5shows the Los Angeles County Estimated Existing
Development of OWTS in the RWQCB regions and watersheds within LA County.
Table 2-1and Table 2-2summarize the number of OWTS by watershed area,
based on the mapped locations on Figure 2-5. Some properties from the
comprehensive inventory list are notincluded in Figure 2-5, Table 2-1 and Table
2-2due to un-mappable addresses and duplicate addresses due to multiple
permits at the file address.
Table 2-1. South County Area (Los Angeles RWQCB Region 4),
Estimated Existing OWTS by Watershed
NOWTS
OWTS
Watershed
Number
Number
Calleguas00
Los Angeles10,951134
San Pedro Channel Islands 30
Watershed
San Gabriel2,54581
Santa Ana1432
Santa Clara (RWQCB Region 4)11,287102
Santa Monica Bay7,238379
55
Table 2-2. North County Area (LahontanRWQCB Region 6),
Estimated Existing OWTS by Watershed
NOWTS
OWTS
Watershed
Number
Number
41
Antelope-Fremont Valleys16,955
1
Mojave127
56
2.5 Water Quality Management Measures
The following discussion describes how the LAMP addresses elements listed
under Section 9.1 of the OWTS Policy for protection of water quality. Areas defined
in Basin Plans where discharges from OWTS are prohibited, such as the Malibu
Civic Center area, and compliance with TMDL implementation plans provide
additional water quality protection in LA County from OWTS.
Groundwater Quality Protection
Soil conditions and lot size. DPH requires detailed soil and site evaluations
during the permit application process in accordance with requirements in the
Plumbing Code and the Professional Guide. The Professional Guide requires
the submittal of a feasibility report with a general soil description and any
features that may affect subsurface wastewater dispersal. Depth of permeable
soil and percolation characteristics below the dispersal field are used to identify
the appropriate siting, design and construction requirements for the OWTS
(Section 3.0). AnOWTSisaprivatesewagedisposalsystemconsistingofa
septictankwheresolidssettleandtheeffluentisdispersedintoaleachfield
orseepagepit.Thismethodreliesupongravityandthenaturalfiltration
capacityofthesoil,whichcausescontaminantstoberemovedfromthe
effluentasitpercolatesdownthroughthesoil.Soil conditions must allow
sufficient absorption and treatment of wastewater discharged through
subsurface dispersal systems to ensure protection of groundwater. A minimum
of 3 feet depth of undisturbed soil shall be available. When there is insufficient
lot area or improper soil conditions for adequate sewage disposal for the
building or land use proposed no building permit will be issued and no OWTS
will be permitted. Where space or soil conditions are critical, no building permit
will be issued until engineering data and test reports satisfactory to the DPH
have been submitted and approved.
Geologic conditions. The site evaluation includes description of slopes and
topographical features, including location of all down banks and man-made
cuts, and unstable land forms, on or off the property. Natural ground slopes in
dispersal areas greater than 30 percent require a slope evaluation report
approvedby a California Certified Engineering Geologist or a California
Registered Professional Soil/Geotechnical Engineer to address any possible
potential for slope destabilization for any proposed hillside installation. The
report shall address whether any unstable land mass or areas subject to earth
slides require a setback of 100 feet or indicate other setbacks that should be
allowed, in accordance with the Professional Guide requirements
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Hydrogeologic conditions. A site-specific hydrogeologic assessment maybe
prepared for site-specific evaluation and must be prepared and certified by a
registered Geologist, Hydrogeologist or Engineering Geologist in accordance
with the Professional Guide requirements. Where the assessment confirms
that neither the proposeddispersal system nor the subject drainage course will
ever generate sufficient lateral infiltration that could negatively impact each
other, declaring the location for the proposed dispersal area suitable, possible
waiver of the setback requirements may be granted by the DPH. The
assessment will be based on a study of the interrelationship between the
geologic conditions and surface and subsurface waters, conducted in at least
one excavation located directly between the dispersal system and the subject
drainage course to a depth not less than 10 feet below the anticipated bottom
of the dispersal system. The hydrogeological assessment will describe the
determining factors and examine the hydrogeological properties that provided
a basis for the conclusion and ensure the protection of groundwater quality.
The assessment will identify the existence of any hydrogeological elements that
could support the possibility of lateral infiltration, such as, high hydraulic
gradients, high hydraulic conductivity of soil,slow-permeable or impermeable
layers, saturated zones, presence of perched water, elevation differential
between the dispersal system and the drainage course, potential inflow of
surface and subsurface water and wastewater, possibility of groundwater
recharge, presence of vegetative growth, seasonal variations and climatic
factors, etc. In situations where hydraulic gradient suggests the possibility of
effluent migration toward the drainage course, even though the hydrogeological
assessment has concluded that OWTS will not have any impact on the
drainage course, the DPH may require a NOWTS with supplemental treatment
and disinfection components.
Groundwater Conditions. Much of the population of the County depends on
water pumped from groundwater sources for water supply and this resource
must be protected from future impacts due to OWTS. The site evaluation must
include evidence of groundwater depth to the satisfaction of DPH. Site plot
plans will show all vegetation and trees, especially oak trees and groundwater
indicators such as willows, reeds, cattails, and other hydrophilic plants to
ensure adequate OWTS siting (See Section 3.4, horizontal setbacks). The
locations of borings to establish current groundwater/subsurface water levels
and percolation tests (including failures and their corresponding percolation
rates) will be clearly documented in the site evaluation. This information helps
determine suitable OWTS design and the minimum vertical separation distance
between the bottom of the dispersal system to groundwater. Requirements for
vertical separation to groundwater are described further in Appendix A and
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include:
-Vertical separation distance of 5 feet for conventional OWTS with
percolation rates between 5 and 60 minutes per inch, a vertical separation
distance of 20 feet for conventional OWTS with percolation rates greater
than 1 minute per inch and less than 5 minutes per inch, and a vertical
separation distance of 10 feet for all seepage pits;
-Los Angeles County does not allow for reduced groundwater separation
distances based on percolation rates, but does allow for reduced vertical
separation distance based on inclusion of supplemental treatment for a
NOWTS dispersal system;
-No provision for vertical separation distance of less than 2 feet.
Areas with High Use of Domestic Wells. Domestic wells are used widely in
rural unincorporated areas that also use OWTS. California State Water
Resources Control Board, Division of Drinking Water regulates the use of
domestic water wells under the Safe Drinking Water Act requirements separate
from this LAMP. In the County the horizontal setbacks from domestic wells are
required to ensure the protection of the groundwater supply from OWTS near
domestic wells. Horizontal setback requirements are summarized in Section
3.4, Table 3-4. The RWQCB may identify specific areas of high domestic well
usage in cumulative impact studies, as discussed in Appendix B, with the
availability of supplemental treatment technologies to mitigate impacts to
groundwater in theseareas if necessary.
Density Limitations. The requirement to install supplemental treatment on new
lot subdivisions that exceed the Tier 1 density limitation based on average
annual rainfall helps protect groundwater from high density development using
OWTS which could overload the assimilative capacity of the groundwater.
Existing lots in the Antelope Valley area under the authority of the Lahontan
RWQCBwill remainsubject to the limitation of 1 single family residence per
half acreor 500 gal/acre/day of wastewaterthat was in effect prior to the
adoption of the LAMP.
Surface Water Quality Protection
Minimum water body setback requirements. Horizontal setbacks from flowing
and non-flowing surface water bodies are required to protect surface water.
Horizontal setback requirements are summarized in Section 3.4, Table 3-4.
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Ifthe site-specificnaturalfiltrationoccurstoofast,thereisanincreased
potential for contaminatedeffluenttoreachthegroundwater and/or nearby
surface water bodies.ItisundertheseconditionsthataNOWTSbecomes
anoptiontocontinuepursuitofabuildingpermit.Whenutilizinga
NOWTS,theeffluentispre-treated,removingcontaminantspriorto
dispersaloftheeffluentintothesoil.Insummary,aNOWTSisusedin areas
wheresoil percolates too fast fornatural filtration tooccur. An OWTS that
utilizes, in addition to the septic tank, one or more supplemental treatment
components to treat the effluent prior to discharge on the dispersal field is
considered a NOWTS. For new construction, apropertyownerwillbe
requiredtoinstallaNOWTSutilizingapre-treatmentcomponentwhena
systemutilizesaseepagepit as well. A NOWTS is requiredwherethe
percolationrateforaspecificsoilisgreaterthan5.12gallonspersquare
orforasystemthatutilizesleach
footofleachingareaper24hours;
lines/fieldswherethepercolationrateforaspecificsoil is fasterthan5
minutes perinch. Section 3.5, below, details the conditions when a NOWTS
is required.
NOWTS may also provide alternatives to a property owner when:
Anexistingprivatesewagedisposalsystemhasfailed; or
Apropertyownerwishestoinstallpressurized drip system.
Flood protection measures. The site evaluation will identify any flood zone/area
within 200 feet of the property line, as required by DPH in the Professional
Guide. The Professional Guide includes additional requirements and
considerations for flood zones, including avoiding installing OWTS within flood
plain/hazard areas. Where suitable sites outside of flood hazard areas are not
available, wastewater dispersal systems may be permitted in flood hazard
areas on sites where the effects of inundation, under conditions of the design,
are minimized. Applicants are advised to contact the local Building and Safety
office to inquire whether additional requirements apply. Due to site constraints
of a property, located within a flood hazard area, the applicant shall be required
to demonstrate that the proposed OWTS is designed with additional protective
measures to prevent contamination of surface water or runoffs and minimize
other risks associated with flooding, such as, infiltration into the dispersal
system when the area is inundated by flood water or the potential of scour over
and into the dispersal system that could adversely impact the absorption
capability of the dispersal system and the overall function of the OWTS.
Public Water Supply. The horizontal setback standards for OWTS components
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are included in this LAMP to protect public water supply features. Further
discussion related to public water supply is included in Appendix A, Section
3.4, Section 4 and Section 5. Table 3-4summarizes horizontal setback
requirements in LA County.
Impaired Water Bodies, Section 303(d) List (Nitrogen or Pathogens).
Impaired water bodies pursuant to Section 303(d) of the Clean Water Act exist
within Los Angeles County. Some of the County impaired water bodies listed due
to nitrogen or pathogen indicators or showing OWTS as a potential contributing
source pursuant to section 303(d) of the Clean Water Act have TMDL levels
established by the RWQCB as shown in Table 2-3. Existing, new, and
replacement OWTS as defined by the State OWTS Policy that are near impaired
water bodies may be addressed by a TMDL and its implementation program, or by
special provisions in a LAMP.
It is the responsibility of the owner of existing, new or replacement OWTS (as
defined by the State OWTS Policy) to confirm whether the location of his/her
system relative to impaired water bodies will classify the system as Tier 3. The
SWRCB provides a map tool on their website
http://www.waterboards.ca.gov/water_issues/programs/owts/index.shtmlthat
assists residents in determining if they are within 2,000 feet of an impaired water
body. This distance is the distance from an impaired water body that the SWRCB
considers to be “near” to a system. If you enter a property address into the map
tool, nearby impaired waters for nitrogen compounds and/or pathogens should be
listed. If no nitrogen -or pathogen-impaired water bodies listed in Attachment 2 of
the OWTS Policy and this LAMP are identified within 2,000 feet of an address,
there is a lower potential for the OWTS to be classified under the Tier 3
requirements or covered under a TMDL implementation plan based on distance to
an impaired water body. If there are nitrogen-or pathogen-impaired water bodies
that are identified within 2,000 feet of an address using the map tool, there is a
higher potential for the OWTS to be classified under the Tier 3 requirements or
covered under a TMDL implementation plan. Due to data limitations, property
owners are strongly advised to conduct further investigation beyond the SWRCB
mapping tool with the help of their local agencies, RWQCB and/or SWRCB to
determine whether their system falls into the Tier 3 category before making any
changes to their system.See the SWRCB website
http://www.waterboards.ca.gov/water_issues/programs/owts/index.shtml.
OWTS near impaired water bodies that are not listed as impaired due to nitrogen
or pathogen indicators, and do not have a TMDL and are not covered by a Local
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Agency Management Program with special provisions, are not addressed by
Tier3. Tier 3 for Impaired Areas is defined as follows:
Tier 3 -Impaired Areas: Existing, new, and replacement OWTS as defined by
the State OWTS Policy that are near impaired water bodies may be addressed
by a TMDL and its implementation program, or special provisions contained in
a Local Agency Management Program. The TMDL and its implementation plan
shall be established by the US Environmental Protection Agency, or adopted
by the County as Basin Plan Amendment(s). If there is no TMDL or special
provisions, new or replacement OWTS within 600 feet of water bodies impaired
for nitrogen or pathogens must meet the specific requirements of Tier 3. In this
LAMP, OWTS near impaired waterbodies and new or replacement OWTS
within 600 feet of water bodies impaired for nitrogen or pathogens must meet
the specific requirements of Tier 3, which includes requirements for
supplemental treatment as a NOWTS as well as inclusion in the Advanced
Protection Management Program (APMP) described in this LAMP.
The impaired water bodies shown in Table 2-3require a 600 feet boundary for
OWTS until a TMDL with OWTS allotment is established by the RWQCB in a TMDL
implementation plan. Tier 3 applies to OWTS within the 600 feet boundary until
the TMDL with OWTS allotment is established. Section 4.2, below provides
additional information for management of OWTS near impaired water bodies.
Until a TMDL with OWTS allotment is established, new or replacement OWTS
within 600 feet of an impaired water body must meet the specific requirements of
Tier 3, which involves inclusion in an APMP. Appendix Bdescribes development
of the APMP. For Tier 3 systems, the APMP requires that supplemental treatment
for nitrogen and/or pathogens must be used, based on the source of impairment
of the nearby water body. Supplemental treatment classifies a system as a
NOWTS, and requirements for NOWTS are described in greater detail in Section
3.5 and Section 3.6, below.
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Table 2-3. Water Bodies Impaired for Pathogens or Nitrogen that are Subject to
Tier 3 in Los Angeles County
RWQCB Impaired Water BodyTMDLImplementation
RegionEffective DatePlan for OWTS
allotment
4Coyote CreekJune 2016–NA
Pathogens
2
4Malibu Creek (Includes Las 2003 and 2013Yes (See
Virgenes Creek and Malibu –NitrogenSection 4.2)
Lagoon)
January 2006–Yes
Pathogens
4
4San Gabriel River Reach 1 June 2016–Yes(See
(Estuary to Firestone)PathogensSection 4.2)
4
4San Gabriel River Reach 2 June 2016–Yes(See
(Firestone to Whittier Narrows PathogensSection 4.2)
Dam)
4
4San Gabriel River Reach 3 June 2016–Yes(See
(Whittier Narrows to Ramona)PathogensSection 4.2)
4San Jose Creek Reach 1 (San June 2016–NA
Gabriel Confluence to Temple Pathogens
Street)
4San Jose Creek Reach 2 (Temple June 2016–NA
Street to Interstate -10 at White Pathogens
Ave.)
4Sawpit CreekMarch 2012–NA
Pathogens
4Walnut Creek Wash (Drains from June 2016–NA
Puddingstone Reservoir)Pathogens
2
4Malibou Lake2003and 2013Yes
–Nitrogen
4Westlake Lake2003 and 2013–Yes
Nitrogen
3
4Santa Clara River Lakes (Lakes 2017–NitrogenYes
Hughes, Muntz, and Elizabeth)
5
4Santa Clara River Reaches 3,5,July 2010 -Yes
6&7Pathogens
Notes:
1.USEPA TMDL approval date.
2.EPA-established TMDL. For Malibu Creek, OWTS allotments for Nitrogen and Phosphorus were
established in the TMDL Implementation Plan (Regional Board, 2017).The implementation plan
includes a study to determine if any areas can be excluded from requirements. No action required
by homeowners until study is completed until 2022.
3.The Santa Clara River Lakes TMDL includes a study to determine if any areas can be excluded. No
action required by homeowners until the study is completed in 2022.
4.San Gabriel River is a concrete lined channel: OWTS do not have an impact on the water body.
5.New or replacement OWTS within 600 feet of the listed reachesmust meet the requirements of Tier
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3.” (See Section 4-2)
NA = No TMDL implementation plan with OWTS allotment has been established yet: “New or
replacement OWTS within 600 feet of an impaired water body must meet the requirements of Tier 3.”
(See Section 4-2)
Las Virgenes Creek, Malibu Lagoon, Westlake Lake, Mint Canyon Creek and
Santa Clara River Lakes (Lakes Hughes, Muntz, and Elizabeth) water bodies are
included in the above list because they have been identified as being impaired for
nitrogen or pathogens with OWTS as a potential contributing source. The
remaining water bodies shown above were identified in the State OWTS Policy as
impaired for pathogens or nitrogen with OWTS as a potential contributing source.
Appendix B includes additional discussion of the water bodies impaired due to
nitrogen and/or pathogens in Los Angeles County.
Subdivision Densities, High Density of OWTS, Parcel Size, and Cumulative
Impacts
The average density for any subdivision of property made by Tentative Approval
pursuant May 13, 2018, to the Subdivision Map Act implemented under this Tier 2
LAMP shall not exceed the allowable OWTS density values in Table 2-4for a
single-family dwelling unit, or its equivalent, for those parcels that rely on OWTS.
The County is adopting these subdivision density specifications from Tier 1 of the
OWTS Policy. The County will accept the use of NOWTS as a variance when the
allowable density cannot be met.The County will require the recordation of a
covenant for the use of a NOWTS.Lots created prior to the implementation of this
LAMP are not subject to the aforementioned minimum lot size requirements,
however they will be subject to the design requirements of this LAMP.
Existing lots in the Antelope Valley area under the authority of the Lahontan Water
Board are subject to the limitation of 1 single family residence per half acre, or a
maximum parcel loading rate of 500 gal/(acre/day) that was in effect prior to the
adoption of the LAMP.
Figure 2-4includes a map of average annual rainfall for the geographic regions in
the County.
As part of the sub-division process, plans and a feasibility study must be submitted
for evaluation and will document adequate area for the DPH requirement for a
100% future expansion area for the OWTS dispersal system. TheRWQCB may
identify specific areas in cumulative impact studies as described in Appendix B,
with the availability of supplemental treatment technologies to mitigate impacts to
groundwater in these areas, if necessary.
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Table2-4.Allowable Average Densities per Subdivision
Average Annual Rainfall Allowable Density
(in/yr)(acres/single family dwelling
unit)
0-152.5
>15 -202
>20 -251.5
>25 -351
>35 -400.75
>400.5
Geographic Areas with Older Non-Conforming OWTS Installations and
Setbacks
Older, non-conforming OWTS may exist in remote rural, recreational or agricultural
areas in the North County, in areas near Malibu, or elsewhere in the County.
Typical non-conforming OWTS are small systems constructed prior to modern
codes. Somesystems consist of cesspools, which are prohibited by the State
OWTS policy. Complaints, applications for updates and/or repairs, and pumper
truck reports help identify non-conforming systems. Non-conforming systems and
cesspools can be upgraded to conforming OWTS or NOWTS depending on space
available. The availability of supplemental treatment technologies may help to
mitigate impacts to groundwater, if necessary. Cesspool phase out is addressed
in Section 4.13. Otherwise, if older systems are not brought into compliance with
the requirements of this LAMP and do not qualify under Tier 0, then the system will
not qualify for conditional waiver from the requirement for owners of OWTS to
apply for and receive Waste Discharge Requirements and the RWQCB should be
contacted.
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3.0 OWTS SITING, DESIGN AND CONSTRUCTION REQUIREMENTS
This section presents excerpts from the Los Angeles County Code Title 11 (Health and
Safety), Title 28 (Plumbing) and the Professional Guide describing the main
requirements for siting, design, operation and maintenance for new and replacement
OWTS in Los Angeles County. As per Section 9.0 of the OWTS Policy, these main
requirements are part of the proposed Tier 2 Local Agency Management Program for
this LAMP. Discussion is included where requirements differ from applicable Tier 1
standards found in Sections 7.0 and 8.0 of the OWTS Policy for low risk new and
replacement OWTS, as appropriate.
3.1 Site Evaluations for OWTS
General Site Evaluation and Siting Standards
Any evaluation for OWTS should first verify that the new, replacement or existing
OWTS as defined by the OWTS State Policy does not lie within an area subject to
a Basin Plan prohibition of discharges from OWTS, such as the Malibu Civic
Center area. Additionally, the evaluation should verify whether the new,
replacement or existing OWTS lies within an area subject to considerations for an
impaired water body, including compliance with a TMDL implementation plan with
OWTS allotment, or within the 600 feet boundary of animpaired water body subject
to Tier 3 and compliance with the APMP (Section 4.2).
When installing, replacing, repairing or modifying an OWTS, plans and a feasibility
report must first be approved by the DPH. The applicant will submit a package to
DPH forapproval, including a service request form, application checklist, fee
payment, feasibility report, and relevant site plans. In all instances, the DPH will
review the submittal package to verify information provided, check proper system
design and determine compliance with site suitability criteria identified in the
Plumbing Code, Professional Guide and LAMP. DPH will identify concerns or
obstacles that may prevent the proposed installation of an OWTS during the site
evaluation.
Feasibility reports will be prepared by qualified professional(s) who possess a valid
California license/permit to conduct the testing, and/or to prepare or contribute to
the preparation of a feasibility report. The QP who prepares the feasibility report
must sign the report. The feasibility report shall clearly identify the following:
The property address, ownership information, the Qualified Professional’s
information, the date of the testing, and the description of the procedures.
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The name and the profession of the person(s) who performed the actual
percolation testing procedure and their working relationship with the QP who
signed the report.
A site-specific determination of seasonal and historical subsurface water levels,
including information regarding the methods utilizedto reach the determination.
This should include all available historical data that supports the findings
concluded by the QP.
Percolation testing data including the failures of test holes.
A general soil description and any features that may affect subsurface
wastewater dispersal.
A soil profile excavation down-logged by a California Professional Geologist or
California Certified Engineering Geologist. This report is to be included with
the percolation test data.
Evidence that the proposed dispersal system meets the setback to
groundwater.
Depth of groundwater in the general area based on prior geological studies of
the area, well completion reports or other relevant sources.
Lot size.
Project estimated flow.
Conformance to density criteria, where applicable.
The feasibility report will describe the site specific natural ground slope and
topographical features, area available for the system and dispersal field, proximity
to cuts, steep slopes, unstable land masses within 100 feet, water bodies, wells,
and other features that limit the available dispersal area, 100% future expansion
area, and horizontal setback requirements. Surface water treatment plants for
drinking water located within 1,200 feet of the system will be identified in the
feasibilityreport as well.
Soil Depth
For existing, new or replacement OWTSas defined by the State OWTS Policy, the
feasibility report will include all necessary soil and site evaluations performed by a
QP, who is retained by the owner. Section 4.4 and Table 4-3summarize the
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education and qualification requirements for a QP. Evaluations will be made in
accordance with requirements in the Plumbing Code, Professional Guide and
LAMP.
A site evaluation shall determine that a minimum of 3 feet of adequate soil depth
is present in the dispersal area. Soil depth is measured vertically to the point where
bedrock, hardpan (a distinct layer of soil that is largely impervious to water), or
impermeable soils are encountered or an adequate depth that has been
determined bythe DPH. Soil depth shall be determined through the use of soil
profile(s) in the dispersal area and the designated dispersal system replacement
area, as viewed in excavations exposing the soil profiles in representative areas,
unless the DPH has determined through historical or regional information that a
specific site soil profile evaluation is unwarranted.
Depth to Groundwater and Percolation Testing
A site evaluation shall determine whether the anticipated highest level of
groundwater within the dispersal field and its required minimum dispersal zone is
not less than prescribed in Table 3-1. Percolation testing shall be completed in
accordance with procedures detailed in the Professional Guide. Prior to
conducting any percolation tests, a site evaluation, including subsurface
exploration, shall be conducted by a California Professional Geologist or a
California Certified Engineering Geologist to determine the depth of groundwater.
Depth to groundwater estimation may use one or a combination of the following
methods:
Direct observation of the highest extent of soil mottling observed in the
examination of soil profiles, as viewed in excavations exposing the soil profiles
in representative areas, recognizing that soil mottling is not always an indicator
of the uppermost extent of high groundwater; or
Direct observation of groundwater levels during the anticipated period of high
groundwater via groundwater exploration test holes; or
In areas with alluvial geology where previous excavations and prior reportsby
Professional Geologists within the property have proven that there are no high
subsurface water concerns, and the soil profile is similar within 10 feet of the
anticipated bottom of dispersal field or seepage pit, a statement signed by a
QP attesting to the data that substantiates the findings may be accepted.
Where a conflict in the above methods of examination exists, the direct
observation method indicating the highest level shall govern.
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In areas that are known to have high groundwater and/or where observation of
mottling, oxidation, staining, crystal buildup, seeps, weeps or other features that
may indicate presence of groundwater in the past or present or where groundwater
or moisture seepage (seeps, perched-water, etc.) is present within 10 feet below
the expected bottom of the dispersal field or seepage pit, the QP shall, on a
continuous basis, monitor and measure the presence of moisture and depth to high
groundwater through a groundwater level observation well. Chapter 8 in the
Professional Guide provides a detailed description of the manner in which to
conduct testing in areas of known or observed high subsurface water.
Depth to groundwater determinations are required on every property unless the
Director determines, on a case-by-case basis, that such testing is not necessary
due to the availability of sufficient information to demonstrate compliance with
applicable siting criteria for all proposed OWTS locations.
Table 3-1. Minimum Vertical Separation to Groundwater for Leach Field and Leach
Bed Dispersal Systems
(feet,belowtrenchbottom)
Los Angeles County LAMP and Plumbing Code
Percolation Rate
Minimum Vertical Separation, Proposed Tier 2
(minperinch)
<1Not allowed
1-<520 feet minimum vertical separation
5-605 feet minimum vertical separation
>60Not Allowed
The depth to groundwater requirements for OWTS in the County are discussed in
greater detail in Appendix A.
Afeasibility reportshall include percolation testing and evaluation of the suitability
of the soils for absorption of wastewater in the dispersal zone. Percolation testing
is required on every property unless the Director determines, on a case-by-case
basis, that such testing is not necessary due to the availability of sufficient
information to demonstrate compliance with applicable siting criteria for all
proposed OWTS locations. Prior to performing percolation testing, the QP will
notify the DPH of the date and time of all percolation tests to be performed, at least
one business day in advance. The DPH representative may visit the site to observe
the testing procedure. The feasibility report will clearly disclose the name and the
profession of the person who performed theactual percolation testing procedure
and the working relationship to the QP consultant who directly supervised the work.
A sufficient number of percolation tests shall be conducted within the anticipated
dispersal system on all properties proposing to use an OWTS. The entire
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percolation test procedures, including presoak shall be performed by a QP or
trained individual(s) that are supervised by the QP. All percolation test rates shall
be performed by presoaking of percolation test holes and continuing thetest until
a stabilized rate is achieved. In the County, percolation test results in the dispersal
field for OWTS will not be faster than five minute per inch (5 MPI) or slower than
sixty minutes per inch (60 MPI). The County requiresincreased groundwater
separation distances based on percolation ratesof at least 1 minute per inch but
slower than 5minutes per inch.The County does allowreduced separationfor
NOWTS dispersal systems as shown in Table 3-2.
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Table3-2. Minimum Vertical Separation to Groundwater with Percolation Rates for
OWTS, NOWTS and Seepage Pits
Min.Depthto
1
PercolationRateGroundwater(feet)
TypeofOWTS
ConventionalSepticTank withleach
1-<520
line, leach field orinfiltrative chambers
ConventionalSepticTank,leach line, 5-605
leach field orinfiltrative chambers
NOWTS with leach lines, leach field, 1-603
or infiltrative chambers
Between 0.83 and 5.12
Seepage Pits, and Gravel-Packed Pitsgallons per square foot in 24
hours
10
Greater than 5.12 gallons
Seepage Pits and Gravel-Packed
Pits –With NOWTS and per square foot in 24 hours
disinfection system.10
Greater than 5.12 gallons 2ft as a variance for
Soil Replacement: the
manufactured/engineered soil shall per square foot in 24 hours existing systems
only.
provide homogenized absorption
capability, requires the use of a Otherwise, 5 ft.
NOWTS that uses disinfection and
an alternate method of wastewater
disposal.
1
Measured fromthebottomof thedispersalsystem
Special Notification to Owner of Surface Water Treatment Plant for Drinking
Water
During the feasibility study, the QP will determine if the OWTS is within 1,200 feet
of an intake point for a surface water treatment plant for drinking water, is in the
drainage catchment in which the intake point is located, and located such that it
may impact water quality at the intake point such as being upstream of the intake
point for a flowing water body. If the OWTS is within 1,200 feet of an intake point
for a surface water treatment plant for drinking water, is in the drainage catchment
in which the intake point is located, and is located such that it may impact water
quality at the intake point:
The DPH will provide a copy of the permit application to the owner of the water
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system of their proposal to install an OWTS within 1,200 feet of an intake point
for a surface water treatment plant. If the owner of the water system cannot be
identified, then the DPH will notify the State Water Resources Control Board,
Division of Drinking Water.
The permit application package will include a topographical plot plan for the
parcel showing the OWTS components, the property boundaries, proposed
structures, physical address, and name of property owner.
Geotechnical Report/Slope Evaluation Report
A Slope Evaluation Report approved by a qualified professional is required
whenever natural ground slopes in dispersal areas are greater than 30%. A
California Certified Engineering Geologist or a California Registered Professional
Soil/Geotechnical Engineer shall address whether any unstable land mass or
areas subject to earth slides require a setback of 100 feet or indicate other
setbacks that should be allowed.
A geotechnical report from a qualified professional will be required for any unstable
land mass or area subject to earth slides when proposed set back distance will be
less than 100 feet.
Cumulative Impact Assessment
During the site assessment and prior to issuing a permit to install an OWTS, the
DPH will consider results from cumulative impact studies, if available.
In specific areas that have been identified as areas of high domestic well usage,
the RWQCB may complete cumulative impact studies for new OWTS installations
based on the number of OWTS systems in the geographic area, as appropriate.
Typically, non-residential and large flow OWTS managed under the RWQCB WDR
permit process would be the greatest contributing factor for such studies. If the
results of cumulative impact studies indicate that OWTS (domestic sources) may
be impacting groundwater, testing including analytes may be recommended by the
RWQCB to constrain the impact of OWTS. The RWQCB may recommend
additional testing for analytes, including nitrogen, bacteria, TDS, chloride, sulfate
and/or boron, as appropriate. Appendix B provides additional discussion of
cumulative impact assessment considerations.
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Subdivision Densities
The average OWTSdensity for any subdivision of property made by Tentative
Approval pursuant to the Subdivision Map Act implemented under this Tier 2 LAMP
shall not exceed allowable density values for a single-family dwelling unit, or its
equivalent, for those units that rely on OWTS (Section 3.0). The County will accept
the use of NOWTS as a variance when the allowable density cannot be met.
3.2 Wastewater Flows for OWTS Design
The design of new and replacement OWTS shall be based on influent wastewater
quality, quantity, the site characteristics and the required level of treatment for
protection of water quality as well as public health. Because of the many variables
encountered, it is not possible to set absolute values for waste/sewage flow rates
for all situations. The designer should evaluate each situation and, if figures in
Table 3-3need modification, they should be made with the concurrence of the
DPH. Estimated flow rates are provided in the County Plumbing Code, as
summarized in Table 3-3.
Table 3-3. Estimated Waste/Sewage Flow Rates
Type of OccupancyUnit Gallons (liters) Per Day
1. Airport15 (56.8) per employee
5 (18.9) per passenger
2. Auto WashersCheck with equipment
Manufacturer
3. Bowling Alleys (snack bar only)75 (283.9) per lane
4. Camps:
Campground with central comfort 35 (132.5) per person
station
Campground with flush toilets, no 25 (94.6) per person
showers
Day camps (no meals served)15(56.8) per person
Summer and seasonal50 (189.3) per person
5. Churches (Sanctuary) 5 (18.9) per seat
with kitchen waste7 (26.5) per seat
6. Dance Halls5 (18.9) per person
7. Factories:
No showers25 (94.6) per employee
With showers35(132.5) per employee
Cafeteria, add5 (18.9) per employee
8. Hospitals 250 (946.3) per bed
Kitchen waste only25 (94.6) per bed
Laundry waste only40 (151.4) per bed
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Type of OccupancyUnit Gallons (liters) Per Day
9. Hotels (no kitchen waste)60 (227.1) per bed (2 person)
10. Institutions (Resident) 75 (283.9) per person
Nursing Home125 (473.1) per person
Rest Home125 (473.1) per person
11. Laundries, self service 300 per machine
(minimum 10 hours per day)
CommercialPer manufacturer's specifications
12. Motel 50 (189.3) per bed space
with kitchen60 (227.1) per bed space
13. Office 20 (75.7) per employee
14. Parks
Picnic parks (toilets only)20 (75.7) per parking space
Recreational vehicles:
without water hookup75 (283.9) per space
with water and sewer hookup100 (378.5) per space
15. Restaurants—Cafeterias50 (189.3) per seat
16. Schools—Staff and office20 (75.7) per person
Elementary students15 (56.8) per person
Intermediate and High20 (75.7) per student
with gym and showers, add5 (18.9) per student
with cafeteria, add3 (11.4) per student
Boarding, total waste100 (378.5) per person
17. Service stations, toilets 1000 (378.5) for 1st bay 500
(1892.5) for each additional bay
Recreational vehicle dump station750
18. Stores 20 (75.7) per employee
public restrooms, add1 per 10 sq. ft.(4.1/m2) of floor
space
19. Swimming pools, public10 (37.9) per person
20. Theaters, auditoriums 5 (18.9) per seat
drive in10 (37.9) per space
3.3 Materials and Equipment
The design of the OWTS system will comply with minimum standards, including
accepted plumbing material standards, as specified in the Plumbing Code.
Materials and equipment for OWTS construction, replacement or repair will be
reviewed and evaluated by theDPH.
Septic tanks must be watertight, properly vented and constructed of reinforced
concrete, heavyweight reinforced concrete blocks, fiberglass or other durable non-
corrodible materials as approved by the director. Septic tanks shall be designed
to withstand any anticipated weight placed above it. All septic tanks shall be listed
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and approved by IAPMO or an ANSI accredited testing organization.
All OWTS approved under the LAMP shall have a septic tank equipped with an
effluent filter located in the outlet compartment in such a manner to be easily
serviced.
Design and materials for special conditions or materials not provided for in the
Plumbing Code shall be permitted to be used only by special permission of the
Director after the Director has been satisfied as to their adequacy. Nothing in the
Plumbing Code is intended to prevent the use of systems, methods, or devices of
equivalent or superior quality, strength, fire resistance, effectiveness, durability,
and safety over those prescribed by the Plumbing Code. If alternative materials
are included in the OWTS design, technical documentation will be submitted to the
DPH to demonstrate equivalency. The Director will have the authority to approve
or disapprove the system, method, or device for the intended purpose.
3.4 Conventional OWTS Requirements
Design requirements for conventional OWTS are detailed in the Professional
Guide and Plumbing Code for the County. There are no key issues related to Los
Angeles County’s LAMP Tier 2 OWTS variations relative to SWRCB Tier 1
requirements. County Tier 2 requirements are as stringent in the protection of
public health and of the environment as SWRCB Tier 1 requirements. However,
the County’s LAMP adopts some horizontal setback minimums not currently
specified in the County’s plumbing code, which will be amended to the Plumbing
Code.
Siting Requirements
The following minimum siting criteria must be met for approval of any conventional
OWTS:
1.A site evaluation shall determine that a minimum of 3 feet of adequate soil
depth is present in the dispersal area. Soil depth is discussed further in Section
3.1, above.
2.The total depth of fill over leach lines to ground level, to include the gravel over
the pipe, shall not exceed 24 inches. A depth of 12 to 18 inches of earthen
cover is required over leach lines.
3.The minimum vertical separation distances to groundwater and the required
soil percolation rates for conventional OWTS are summarized in Section 3.1,
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above. The OWTS must comply with the vertical separation distances shown
in Table 3-1.
4.Where suitable sites outside of flood hazard areas are not available,
wastewater dispersal systems may be permitted in flood hazard areas on sites
where the effects of inundation, under conditions of the design, are minimized.
Applicants are advised to contact the local Building and Safety office to inquire
whether additional requirements apply.
5.Where natural ground slopes in dispersal areas are greater than 30%, approval
for a conventional OWTS is dependent on the findings of the slope evaluation
report prepared by a qualified professional.
6.The OWTS must comply with the horizontal setbacks shown in Table 3-4.
Additional discussion of horizontal setbacks is included in Appendix A.
Table3-4. Minimum Horizontal Setback Distances
Minimum Horizontal Distance Septic Disposal Seepage
in Clear Required From:TankFieldPit
5 feet 8 feet 8 feet
1
Buildings or Structures
(1.52 m)(2.44 m)(2.44 m)
Property line adjoining private 5 feet 5 feet 8 feet
property(1.52 m)(1.52 m)(2.44m)
Public Water Well, Where
200 feet 200 feet
depth of effluent dispersal —
8
(61 m)(61 m)
7,8
system >10 feet
Public Water Well, Where
150 feet 150 feet
depth of effluent dispersal —
(45.7m)(45.7m)
7
96,96,9
Springs, and Flowing Surface 100 feet100 feet150 feet
7,9
Water(30.5m)(30.5m)(45.7 m)
Vernal Pools, Wetlands, Lakes,
106,106,10
200 feet200 feet200 feet
Ponds, or Other (Non-Flowing)
(61m)(61m)(61m)
7,10
Surface Water Bodies
5 feet 5feet12 feet
Seepage pits
(1.52m)(1.52 m)(3.66 m)
4
5 feet 4 feet5 feet
Disposal field
(1.52m)(1.22 m)(1.52 m)
On site domestic water service 5 feet 5 feet 5 feet
line(1.52m)(1.52 m)(1.52 m)
5 feet 5 feet
Distribution box—
(1.52 m)(1.52 m)
10 feet 10 feet 10 feet
Pressure public water main
(3.05 m)(3.05 m)(3.05 m)
78
100 feet 100 feet 150 feet
7
Private Water Wells
(30.5 m)(30.5 m)(45.72m)
100 feet 100feet 100 feet
11
Monitoring wells
(30.5 m)(30.5 m)(30.5 m)
Unstable Land Mass or Areas 100 feet 100 feet 100 feet
12
Subject to Earth Slides(30.5 m)(30.5 m)(30.5 m)
High Water Mark of Reservoir,
400 feet 400 feet 400 feet
Lake, or Flowing Water Body,
(122 m)(122 m)(122 m)
13
Type I
High Water Mark of Reservoir,
200 feet 200 feet 200 feet
Lake, or Flowing Water Body,
(61 m)(61 m)(61 m)
14
Type II
10 feet 10 feet 10 feet
15
Trunk of any tree
(3.05 m)(3.05 m)(3.05 m)
Notes:
When disposal fields and/or seepage pits are installed in sloping ground, the minimum horizontal distance
between any part of the leaching system and ground surface shall be fifteen (15) feet (4.57m).
1.Including decks, patios, porches and steps, whethercovered or uncovered, breezeways, roofed porte-
cocheres, roofed patios, carports, covered walks, covered driveways and similar structures or
appurtenances.
2.Reserved.
3.Reserved.
4.Plus two (2) feet (.61m) for each additional (1) foot (.305m) of depth in excess of one (1) foot (.305m)
below the bottom of the drain line. (See also Section K 6 in Appendix K of the Plumbing Code.)
5.Reserved.
6.These minimum clear horizontal distances shall also apply between disposal field, seepage pits, and the
ocean mean higher high tide line.
7.Where special hazards are involved, the distance required shall be increased as may be directed by the
Authority Having Jurisdiction.
8. If the depth of the effluent dispersal system exceeds 20 feet (6.1m) and is within600 feet (182.88m) of a
public water well, the setback must be such that there is at least two-year travel time for microbiological
contaminants
9. Includes springs and flowing surface water bodies where the edge of that water body is the natural or
levied bank for creeks and rivers, or may be less where site conditions prevent migration of wastewater to
the water body.
10. Distance from vernal pools, wetlands, lakes, ponds, or other surface water bodies where the edge of
that water body is the high water mark for lakes and reservoirs, and the mean high tide line for tidally
influenced water bodies.
11.Where regulatory or legitimate data requirements necessitate, the required distance to monitoring wells
may be decreased as may be directed by the AuthorityHaving Jurisdiction. If the monitoring well is installed
to monitor the groundwater at the waste effluent discharge, the setbacks do not apply.
12. Unstable land mass or areas subject to earth slides shall be identified by a registered engineer or
registered geologist; other setback distances are allowed, if recommended by a geotechnical report
prepared by a qualified professional.
13. 400 feet (121.92m) from the high water mark of a reservoir, lake, or flowing water body when the effluent
dispersal systemis within 1,200 feet (365.76m) from a public water systems’ surface water intake point,
within the catchment of the drainage, and located such that it may impact water quality at the intake point
such as upstream of the intake point for flowing water bodies.
14. 200 feet (60.96m) from the high water mark of a reservoir, lake, or flowing water body when the effluent
dispersal system is located more than 1,200 feet (365.76m) but less than 2,500 feet (762m) from a public
water systems’ surface water intake point, within the catchment of the drainage, and located such that it
may impact water quality at the intake point such as upstream of the intake point for flowing water bodies.
15. For Oak trees, this requirement extends to 5 feet (1.52m) outside of the drip line or 15 feet (4.57m) from
the trunk, whichever is greater.
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Septic Tank Requirements
Septic tanks must have the minimum capacity shown inTable 3-5for single family
and multiple dwelling units. The capacity for a septic tank to be utilized for single
or multiple family dwelling shall be determined based on the number of bedrooms
and bedroom equivalents. Septic tanks may be voluntarily oversized to improve
the retention time, which should be clearly noted on the plans.
Table 3-5. Capacity of Septic Tanks*
Single-Family Multiple Dwelling Other Uses:
Minimum Septic
Dwellings** Units or Maximum Fixture
Tanks Capacity in
Number of Apartments—One Units Served (per
Gallons (Liters)
BedroomsBedroom EachPlumbing Code)
1 or 215750(2,838)
3201,000 (3,785)
42 units251,200 (4,542)
5 or 63331,500 (5,677.5)
4452,000 (7,570)
5552,250 (8,516.3)
6602,500 (9,462.5)
7702,750 (10,408.8)
8803,000 (11,355)
9903,250 (12,301.3)
101003,500 (13,247.5)
Notes:
Extra bedroom, 150 gallons (568 liters) each.
Extra dwelling units over 10,250 gallons (946 liters) each.
Extra fixture units over 100, 25 gallons (95 liters) per fixture unit.
*Septic tank sizes in this table include sludge storage capacity and the
connection of domestic food waste disposal units without further volume
increase.
**Applies to mobile homes not installed in a mobile home park.
Structuralrequirements for septic tanks include the following items:
All new septic tanks shall comply with the most current version of the Los
Angeles County Plumbing Code, Title 28, Appendix K.
All new or replacement tanks shall be approved by IAPMO or stamped and
certified by a California registered civil engineer as meeting industry standards
and their installation shall be according to manufacturer’s recommendations.
New and replacement tanks on conventional OWTS shall be equipped with an
effluent filter to prevent the solids in excess of 3/16th of an inch from passing
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to the dispersal area. All filters shall meet NSF 46 certification standards.
All joints between the septic tank and its components shall be watertight and
constructed of solid, durable materialsto prevent excessive corrosion or decay.
The inverts of all outlets shall be level and the invert of the inlet shall be at least
one inch higher than the outlets.
All septic tank access points shall have watertight risers the tops of which are
set not more than six (6) inches below grade. Access openings at grade or
above shall be locked or secured to prevent unauthorized access.
Any tank proposed to be installed within a driveway must be traffic-rated and
equipped with traffic-rated risers with traffic-rated covers set at grade. Non-
traffic rated tanks shall not be installed within 5 feet of any road or driveway.
OWTS that utilize pumps to move effluent from the septic tank to the dispersal
system shall be equipped with one of the following: a visual, audible, or
telemetric alarm that alerts the owner or service provider in the event of pump
failure. All pump systems shall, at minimum, provide sufficient storage space
in the pump chamber during a 24-hour power outage or pump failure and shall
not allow anemergency overflow discharge. The capacity for the storage
space for pump chamber shall be equal or greater than the sum of 300 gallons
for first bedroom and 150 gallons for each additional bedrooms or bedroom
equivalent rooms thereafter.
When the existing system is required to be exposed to establish the size and
capacity of the septic tank and/or dispersal field or seepage pit, the Department
may visit the site and verify the dimensions with the QP/QC. The QP/QC shall
notify this Department of the date and the time of the uncovering of the OWTS,
at least one business day in advance for possible observation by the
Department representative.
Percolation Rate and Dispersal Methods for Conventional OWTS
Leach Fields and Leach Beds:
Theaveragesoilpercolationrateintheproposeddispersalfield areashall
notbefasterthanfiveMPI(5MPI)norslowerthansixty MPI (60MPI), using
the methods presented in the Professional Guide and Plumbing Code.The
minimum effective absorption area in disposal fields is predicated on the
required septic tank capacity and estimated waste/sewage flow rate.
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Dispersalsizing required by the OWTS Policy uses the maximum
application rate determined from stabilized percolation rates provided in the
OWTS Policy, or from soil textures and structures determined in the OWTS
Policy. This LAMP utilizes the Ryon Formula and actual system testing to
insure an appropriate disposal system sizing for the local soil conditions.
Additional discussion of the dispersal system sizing methodology is
provided in Appendix A.
The conventional leach bed system consists of multiple perforated lines installed
in an excavation with a minimum 36 inches in width, maximum of 100 linear feet in
length and containing 12 to 36 inches of gravel beneath a system of perforated
distribution pipes through which sewage effluent seeps into the surrounding soil.
Perforated pipes shall neither be installed greater than 6 feet apart nor closer than
3 feet tothe sidewall of the leach bed. The area designated as a leach bed shall
be at least 50% greater than the area required for leach lines. The dispersal
field/area may not be covered or paved over and in no case may a vehicle be
driven or placed over the dispersal field/area.
The conventional leach line system consists of one or more trenches. Each trench
shall be 36 inches in width, maximum of 100 feet in length, and contain 12 to 36
inches of gravel beneath a single perforated distribution pipe through which
sewage effluent seeps into the surrounding soil. When more than 1 leach line is
required to be installed, they shall be equal in length and size and be provided
effluent from a distribution box rather than an overflow pipe connecting the leach
lines in series. The distance between trenches shall be a minimum of 4 feet,
measured from closest sidewall to sidewall. The distance between trenches shall
be increased by 2 feet for every additional foot of gravel beneath the perforated
lines. Leach lines onhillside properties shall be installed level with the contour of
the land.
An infiltrative chamber system consists of semicircular chambers installed
contiguously with the open portion of the infiltrative chambers on the ground. The
infiltrative surface area credit shall be limited to the calculated floor area beneath
the open portion of the chamber, excluding the area beneath the base of walls
where infiltrative chamber is placed on the ground. The infiltrative surface area
may be reduced to seventy percent (70%) of the area that it would be required for
a conventional leach field dispersal system. Use of gravel under the infiltrative
chambers is optional; however, no additional sidewall credit will be given when
gravel is used.
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All gravel, stone, slag and similar materials used for filtration purposes shall be
thoroughly washed to be free of fines (small particles). More detailed information
regarding OWTS system design is provided in the Professional Guide and
Plumbing Code.
Seepage Pit
The seepage pit system consists of one or more covered circular excavations, four
to six feet in diameter with an interior lining of six inches of gravel and sewer brick
or concrete liners allowing effluent to seep into the surrounding soil. The pit shall
have a minimum effective sidewall of 10 feet below its sewer inlet pipe.
The seepage pit(s) must be sized to hold a volume of at least five (5) times the
volume of the proposed size of the septic tank divided by the amount of water
absorbed during the percolation test. When groundwater depth prevents a single
pit from meeting this requirement, additional seepage pits must be constructed.
Multiple seepage pits shall have effluent delivered to them from a distribution box
rather than connecting the pits in series.
The installation of a seepage pit is only allowed as part of an existing, conventional
OWTS when it is required to install the future expansion area, the soil meets
percolation rate requirements, and inadequate surface area exists for leach lines
or a leach field.
The installation of seepage pits for new construction requires the use of a NOWTS
with the exception of new construction meeting the following conditions, which will
be allowed the use of a conventional OWTS:
-One unit dwelling with maximum 4 bedrooms or 1,200-gallontank.
-All setback requirements are met.
-The soil characterization does not include bedrocks.
Gravel packed pits are seepage pits that are filled with gravel of ¾ to 2 ½ inches
in size up to the cap level, allowing effluent to seep into the surrounding soil. The
gravel must be washed and free of silt. All of the limitations on seepage pits apply
to gravel packed pits.
The gravel packed pit(s) must be sized to hold a volume of at least five (5) times
the volume of the proposed size ofthe septic tank divided by the amount of water
absorbed during the percolation test. The same requirements for percolation
testing of a seepage pit apply to a gravel packed pit if the test is performed without
gravel pack being added.
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Future Expansion Area
Every new conventional OWTS and new NOWTS, regardless of the type of the
dispersal system, shall be provided with a sufficient land area for an entirely new
dispersal system (100% future expansion area):
When soil profile and percolation tests confirmalluvium geology and uniformity
in geology has been established by the Professional Geologist, the required
percolation testing for the 100% future expansion area may be waived. The
uniformity in geology shall be established through both soil profile studies and
percolation testing of more than one hole.
Where proposed future expansion areas are in bedrock, hardpan or fractured
rock formation, the future pits shall be tested to establish percolation rates for
each individual pit.
If the dispersal system proposed for the 100% future expansion area is installed
concurrently with the construction of a new system, the future expansion system
may not be utilized until the present system has failed.
Any expansions beyond the current footprint of the existing structure or addition of
any new detached structures, shall require the demonstration of the feasibility of
installing the 100% future expansion area, regardless of whether the proposed
renovation will increase the design flow or demand greater capacity than the
existing OWTS:
As a part of an approval for 100% future expansion, a previously approved
existing OWTS that has been in service for more than 15 years is required to
be inspected by a Qualified Contractor.
If previous approval of the OWTS is not available or did not include approval of
the 100% future expansion area AND the renovation/expansion neither
increases the design flow, nor demands a greater capacity, the existing OWTS
shall be evaluated by a Qualified Contractor, in addition to proving outthe 100%
future expansion area by a Qualified Professional.
When the present dispersal system has failed and the 100% future expansion area
is to be utilized,the new dispersal system shall be interconnected with the existing
system with an approved flow diversion device to allow the alternate use of the two
dispersal systems.
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An expansion of up to 10% of the current footprint may be allowed without requiring
to prove out the feasibility for the 100% future expansion area so long as the
expansion:
Does not increase the design flow or require greater capacity,
Does not take up more than 10% of the remaining available undeveloped area
on the property, where no unfavorable geological conditions, such as, bedrock
formation, etc. exist,
All required setbacks can be met,
The location and direction of the proposed expansion is in a manner that will
not interfere with the installation of the 100% future expansion area when
needed in the future.
Applicants who elect to utilize the exemption under 10% expansion rule, shall
submit a signed statement from a California Professional Geologist or a
California Certified Engineering Geologist substantiating that there are areas
available on the property for the installation of the 100% future expansion area
and there are no unfavorable geological conditions, such as, bedrock
formation, etc. exist within the property that may prevent the installation of the
100% future expansion area when needed in the future.
Only one use of the 10% expansion rule will be granted to a property.
In situations where adequate land is not available for a second 100% future
expansion area, the dispersal system that is being installed shall be equipped with
supplemental treatment component. Additionally, the effectiveness of the 100%
future expansion area (dispersal system) shall be determined in accordance with
similar procedures required for the present dispersal system. Moreover, the 100%
future expansion area shall be capable of supporting the installation of a dispersal
system of the same capability and characteristics as the present dispersal system.
When approving a future expansion area for a system without prior approval, the
approval issued by the Department will only encompass the 100% future
expansion area, approving only the renovation/expansion and not the existing
OWTS. The Department may require other additional improvements to ensure that
the minimum required standards have been met.
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3.5 NOWTS Requirements
Non-conventional Onsite Wastewater Systems (NOWTS) perform additional
treatment of effluent to reduce its impact on the environment. This usually includes
the effluent being pumped in small amounts to a specialized filter media where the
effluent is processed mechanically, chemically, and biologically. These processes
include treatment by aerobic bacteria to reduce the Biological Oxygen Demand
(BOD) and convert ammonia to nitrate as well as mechanical filtration of
suspended solids. Areduction in total nitrogen is accomplishedby an aerobic
treatment unit, media filters, sand bed filters or fixed film processors.In the areas
of the Countyregulated by the Los Angeles Regional Water Quality Control Board,
NOWTS are required to include a disinfection systemunder the following
conditions:
o A NOWTS is required with thenewconstruction of a house of more than 4
bedrooms using aseepage pit or where the percolation rate exceeds the
accepted rate for a replacement seepage pit (exceeding 5.12 gallons per
square foot of dispersal area per 24 hours).
o A NOWTS with or without an alternate method of wastewater dispersal may
be used where the percolation rate exceeds accepted rates for a leach line
thth
to 6inchand less
or leach bed (faster than 5 minutes for the drop of the 5
than 20 feet vertical separation from groundwater).
o A NOWTS will be required when there is less than three (3)feet, but at least
two (2) feetof continuous, natural, undisturbed soilunderneaththe
proposed dispersal system, which is a variance allowed for replacement
systems only. The dispersal field may not overlie groundwater protected
for drinking water supplies.
o Soil replacement in conjunction with a NOWTS with an alternate method of
wastewater dispersal is required where the percolation rate is slower that
thth
accepted(slower than 60 minutes for the drop of the 5to 6inch for a
leach line or leach bed system) or when there is less than two (2) feet of
continuous, natural, undisturbed soil below the proposed dispersal system.
Thisis a variance allowed for replacement systems only.The dispersal field
may not overlie groundwater protected for drinking water supplies. Soil
replacement is further discussed in section 3.5 including definition and
process.
o A NOWTS with an alternate method of wastewater dispersal is required
86
where groundwater or surface water setbacks cannot be met, if space
permits. Systems other than NSF 245 certified can be utilized if the licensed
qualified contractors can demonstrate they have the knowledge to design
and install those systems. Thisis a variance allowed for replacement
systems only.Examples of such systems may be mound or horizontal
seepage pits.
o ANSF 245 certifiedNOWTS with or without an alternate method of
wastewater dispersal is required near an impaired water body. If the water
body is impaired for nitrogen, a disinfection component is not required.
o ANSF 245 certifiedNOWTS is required in a TMDL area. The addition of a
disinfection system is required for a TMDL for pathogens.
o A NOWTS with disinfection system is required in situations where an
alternative setback for a drinking water well is used because a normal
setback cannot be achieved.
In the areas of the Antelope Valley regulated by the Lahontan Regional Water
Quality Control Board,the need for a disinfection system shall be evaluated on a
case-by-case basis, and chlorine shall not beused unless all othermeans of
disinfectionhave been deemed not feasible.This is needed to prevent the
formation of chlorine disinfection byproducts, which are carcinogens.
Section 2.5 provides additional information regarding impaired water bodies.
Table 2-3 lists the current water bodies impaired for pathogens or nitrogen that are
subject to Tier 3 in Los Angeles County and require management under the APMP
within this LAMP (Appendix B). The APMP requires supplemental treatment with
a NOWTS within the 600 feet boundary near impaired water bodies.
Site evaluation, plans, operation and maintenance guidelines, other permitting
requirements, design and construction for NOWTS shall conform to all
requirements for conventional OWTS as well as any additional requirements
specified in the Professional Guide and Plumbing Code for the type of NOWTS
proposed.
Required Soil Depths
A site evaluation shall determine that a minimum of 3 feet natural soil depth is
present in the dispersal area. Soil depth is measured vertically to the point where
87
bedrock, hardpan, or impermeable soils are encountered or an adequate depth
that has been determined by the DPH. Soil depth shall be determined through the
use of soil profile(s) in the dispersal area and the designated dispersal system
replacement area, as viewed in excavations exposing the soil profiles in
representative areas, unless the DPH has determined through historical or regional
information that a specific site soil profile evaluation is unwarranted.
Vertical Separation to Groundwater
The County allows for alternative NOWTS dispersal systems as shown in Table 3-
2(Minimum Vertical Separationto Groundwater with Percolation Rates for OWTS,
NOWTS and Seepage Pits).
Horizontal Setbacks
Horizontal Setback requirements for new developments using NOWTS are the
same as the requirements for conventional systems (Table 3-4). Where the
horizontal setbacks cannot be met for a replacement system, approval from the
Director is required. If approval is not granted, applicants can refer to the Regional
Water Board for the issuance of a Wastewater Discharge Requirement (WDR).
Jurisdictional Building and Safety requirements may still apply for the authorization
to install the system regardless of the WDR.
Soil Replacement
For the purposes of this document, soil means the naturally occurring body of
porous mineral and organic materials on the land surface, which is composed of
unconsolidated materials, including sand, silt, and clay particles mixed with varying
amounts of fragments and organic material. Where undisturbed earth has
insufficient depth to satisfy the minimum depth requirements or has poor
absorption rate, engineered soil with similar composition characteristics of loamy
sand, certified by a California Registered Professional Soil/Geotechnical Engineer,
may be added to the existing native soil so that the site conditions meet or exceed
the specific depth and absorption rate requirements. The engineered soil shall be
re-composed and re-graded uniformly to providehomogenized absorption
capability, equivalent to soil category of loamy sand. The qualified professional
shall prove through sieve analysis and other quantifying tests that thedesirable
compositionandcompactionhasbeenachieved.Thecompaction characteristics
of the engineeredsoil shall correspond as close as possible to the native soil of
the surrounding area. Adequate number of percolation tests shall be conducted in
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the area where engineeredsoil has been provided to confirm that the percolation
rates are in correlation with loamy sand soil category. The results of the
percolation tests conducted in the area shall affirm uniformity in soil composition
and compaction.
Additional requirements:
A pressurized distribution system is required where engineered soil is used in
order to comply with the minimum soil depth and/or the absorption rate
requirements. Pressurized distribution means a type of dispersal system that
employs a pump and distribution piping with small diameter perforation (1/4 of
an inch or less) or drip emitters that are installed at a depth of 6 inches (Tier 1
requirement) below grade and a minimum of 6 inches apart or as
recommended by the manufacturer and approved by the DPH, to distribute
effluent into soil with uniform distribution.
Soil replacement shall not compromise the protection of the groundwater; a
minimum of 5 feet of separation to groundwater from the lowest point of the
dispersal system shall be allowedfor new constructionand a minimum of 2 feet
for replacement systems.
Percolation testing shall be done in those areas where engineered soil has
been provided to ensure that new soil meets or exceeds the absorption rate
requirements.
Engineered soil shall compensate for the lack of in-place soil at a ratio of 1.5 to
1;so that a 1-foot deficiency in the soil column depth would require 1.5 feet of
engineered soil material. In no case shall engineered soil compensate for more
than 2 feet of the minimum native soil depth requirements.
NOWTS Design and Constructions Requirements
Allsupplementaltreatmentsystemsandcomponentsshallbeinstalledand
operatedinaccordancewiththeirrespectivemanufacturer’srecommendations
andaresubjecttoreviewandacceptancebytheDPH. Acceptanceof
supplementaltreatmentsystemsbytheDPHiscontingentupona
demonstration through extensive field and test data confirming that the
supplemental treatment system will produce continuous and long-range results.
Systems with NSF 245 certification are considered to meet this requirement. This
acceptanceissubjecttorevocationwhenthesupplementaltreatmentsystem
isdeemedinadequate bythe DPH.
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Thesupplementaltreatmenttechnologybeingdemonstratedshallmeetor
exceedsecondarytreatmentstandardsandshallprovidereductionin
BiochemicalorCarbonaceousBiochemicalOxygenDemand(BOD/CBOD),Total
SuspendedSolids(TSS)concentrationsandTotalNitrogenasprescribed
further.
The following requirements shall apply to Supplemental Treatment Units:
Systems must be NSF 245 certified, or equivalency determined through
demonstration testing unless they are installed for bacteriological reduction as
a result of Tier 3 requirements. If the systems are only required to treat for
bacteria, the systems must be NSF 40 certified.
For disinfection, the State OWTS Policy requires that supplemental treatment
components be designed to provide sufficient pretreatment of the wastewater
so that effluent from the supplemental treatment components does not exceed
a 30-day average TSS of 30 mg/L and shall further achieve an effluent fecal
coliform bacteria concentration less than or equal to 200 Most Probable
Number (MPN) per 100 milliliters.
Tanks must be IAPMO or similarly certified.
Supplementaltreatmentcomponents,otherthanthatofdisinfection,shallbe
designedtoreducetheconcentrationofBOD/CBOD,TSS andTotal Nitrogen
(TN).
Supplementaltreatmentcomponents,otherthanthatofdisinfection,shall
produceaneffluentconcentrationlevelthatmeetsorsurpassesthefollowing
requirements:
-BOD –30 mg/L or CBOD5 –25 mg/L
-TSS –30 mg/L
-Total Nitrogen –At least a 50% average reduction of influent (Total
Nitrogen)
-pH –6.0 to 9.0 SU
NOWTS shall be equipped with a visual or audible alarm as well as a telemetric
alarm that notifies the owner and the service provider of the NOWTS in the
event of system malfunction. The telemetric monitoring system shall be
capable of continuously assessing the operation of the supplemental treatment
system. The owner must enter a covenant with the County prior to approval of
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the system.
NOWTS shall be monitored by a service provider who is certified by the
components’ manufacturer and maintains the NOWTS in accordance with the
operation and maintenance manual for the components and as prescribed by
the DPH. The NOWTS designed to meet the treatment performance
requirements outlined above shall be inspected by the service provider as
frequently as needed or more frequently as required by the DPH to ensure
proper operation at all times. The reportsof all maintenance records shall be
forwarded to the DPH on a quarterly basis or more frequently as deemed by
the DPH.
NOWTS installed to meet the supplemental treatment requirements for
pathogensin Tier 3 water body impaired or TMDL areas shall be subject to
annual effluent testing.Effluent samples shall be taken by service provider
under contract at the point of discharge; the sample shall then be taken to a
ELAPcertified laboratory for such analysis. The results of the laboratory
analysis shall be forwarded to DPH. The lab report shall clearly specify the
location/address where sample was taken from. The laboratory analysis must
include TSS. The bacteriological analysisshall consist of the totalcoliform
bacteria.The lab results must confirm that the supplemental treatment water
quality and bacteriological standards described above are met.
Annual effluent testing will be required for NOWTS installed in the portion of
the Antelope Valley regulated by the Lahontan Regional Water Quality Control
Board at a commercial, industrial or institutional setting only.
NOWTS owners must enter into an agreement with the County prior to approval
of their systems.
The data provided in monitoring laboratory analysis reports are subject to
verification by the DPH.
NOWTS owners are required to obtain an annual Public Health Permit upon
issuance of the Certificate of Occupancy by Building and Safety.
The DPH may exercise the option of requiring samples to be taken while a DPH
representative is present and/or by an independent party authorized by the DPH.
Standard requirements to ensure proper “Chain of Custody” shall apply.
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3.6 Types of NOWTS Permitted
NOWTS have three components; a supplemental treatmentsystem, a disinfection
systemwhen required bytheDPH, and may have an alternate method of
wastewater effluent dispersal.
The supplemental treatment system can be either an aerobic treatment unit, a
packaged treatment plant, other systems NSF 245 certified, or any systems
approved by the DPH based on performance assessment to provide effluent
quality equal to the standards for NSF 245 certification.
For disinfection, the State OWTS Policy requires that supplemental treatment
components be designed to provide sufficient pretreatment of the wastewater so
that effluent from the supplemental treatment components does not exceed a 30-
day average TSS of 30 mg/L and shall further achieve an effluent fecal coliform
bacteria concentration less than or equal to 200 Most Probable Number (MPN) per
100 milliliters.
Alternative methods of wastewater effluent can either be a pressurized dosing
system,a moundsystem,a pressurized subsurface drip dispersal system,or other
technologies meeting compliance.
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4.0 SPECIAL OWTS MANAGEMENT ISSUES
The below discussion describes provisions under Tier 2 in this LAMP for special OWTS
management issues as per sections 9.2.1 through 9.2.12 of the OWTS Policy.
4.1 OWTS and NOWTS Inspection, Monitoring, Maintenance and Repair
Requirements for inspection, monitoring, maintenance and repair are summarized
in Table 4-1below. All systems for which a permit is required will be inspected,
which is a requirement from the Plumbing Code, Chapter 1, Section 104. No
portion of any system shall be concealed until inspected and approved. The DPH
nor the county is liable for expense entailed in the removal or replacement of
material required to permit inspection. Approval as a result of an inspection shall
not be construed to be an approval of a violation of the provisions related to OWTS
or of other codes and laws. Inspections presuming to give authority to violate or
cancel the provisions related to OWTS or other codes and laws shall not be valid.
Table 4-1 Summary of Los Angeles County Provisions for OWTS/NOWTS
Inspection, Monitoring, Maintenance and Repairs
ActivityCode or InspectionsMonitoringMaintenance Permit
Professional & RepairsRequired
Guide
Site
Evaluation
Plumbing Code Building and
for setbacks
NOWTSandSafety and EH
Leak Test N/AN/A
ConstructionProfessional approvals
Start up and
Guiderequired
telemetry
test
Telemetry
monitoring
by service
provider.
Service
Tier 3 for
Annual
pathogens:acontract
Inspection
Title 11 and required.
nnual
NOWTS by aPublic Health
Professional effluent Maintenance
Operation
qualified Permit
Guidetesting/schedule as
septic
Annual specified by
technician
effluent manufacturer
testing in
Lahontan
RWQCB
area
93
ActivityCode or InspectionsMonitoringMaintenance Permit
Professional & RepairsRequired
Guide
Plumbing Code Building and
Site
OWTS andSafety and EH
evaluation N/AN/A
ConstructionProfessional approvals
for setbacks
Guiderequired
Maintenance,
including
pumping of
OWTS
N/ANoneNonesludge every None
Operation
3-5 years
recommende
d
Performance
inspection
required by
QC prior to
application Maintenance,
for building repair,
addition or system
remodel; May involve upgrade, and
OWTS/NOWTPlumbing Code evaluation water designation Building and
S Building andprocedures sampling, of future Safety and EH
Additions & Professional specified in dye testing expansion approvals
RemodelsGuideProfessional or other area may be required
Guide. EH monitoringrequired as
conducts per
inspection of Professional
setbacks Guide
after
submission
of
application.
94
ActivityCode or InspectionsMonitoringMaintenance Permit
Professional & RepairsRequired
Guide
Inspection of
OWTS
Maintenance
conducted
and/or
by
May involve repair/system
independent
water upgrade work
Point of Sale maintenance
sampling, may be
InspectionsN/Aprovider or N/A
dye testing recommende
professional
or other d or required
in
monitoringas a result of
conjunction
inspection
with sale of a
findings.
property or
re-financing.
Inspections
Maintenance
of
May involve and/or repair
OWTS/NOW
Complaint water work/system
TS by EH
Investigationsampling, upgrademay
Title 11staff in N/A
sdye testing be required
response to
(Abatement)or other as a result of
complaints
monitoringinspection
or observed
findings.
violation(s).
4.2 OWTS Near Impaired Water Bodies
As described in Section 2.5, the below impaired water bodies are listed pursuant
to section 303(d) of the Clean Water Act for impairment due to nitrogen or
pathogen indicators. Some of these impaired water bodies have TMDL levels
established by the RWQCB.
OWTS near impaired water bodies that are not listed as impaired due to nitrogen
or pathogen indicators, and do not have a TMDL and are not covered by a Local
Agency Management Program with special provisions, are not addressed by Tier
3.
No other special provisions related to impaired water bodies have been adopted
for OWTS in Los Angeles County.
Table 2-3in Section 2.5, above, summarizes the current statusof TMDLs for
relevant impaired water bodies. Figure 4-1shows the water bodies in Los Angeles
County that are impaired due to nitrogen or pathogen indicators.
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Water Bodies Impaired for Pathogens Subject to Tier 3:
Coyote Creek
Malibu Creek (Includes LasVirgenes Creek and Malibu Lagoon)
San Gabriel River Reach 1 (Estuary to Firestone)
San Gabriel River Reach 2 (Firestone to Whittier Narrows Dam)
San Gabriel River Reach 3 (Whittier Narrows to Ramona)
San Jose Creek Reach 1 (San Gabriel Confluence to Temple Street)
San Jose Creek Reach 2 (Temple Street to Interstate -10 at White Ave.)
Sawpit Creek
Walnut Creek Wash (Drains from Puddingstone Reservoir)
Santa Clara RiverReaches 3, 5, 6 & 7
Water Bodies Impaired for Nitrogen Subject to Tier 3:
Malibu Creek (Includes Las Virgenes Creek and Malibu Lagoon)
Westlake Lake
Santa Clara River Lakes (Lakes Hughes, Lake Muntz, and ElizabethLake).
The above impaired water bodies require a 600 feet boundary for OWTS until a
TMDL with OWTS allotment is established by the RWQCB in a TMDL
implementation plan. Until a TMDL with OWTS allotment is established, new or
replacement OWTS within 600 feet of animpaired water body must meet the
specific requirements of Tier 3, which involves inclusion in an APMP. Appendix
Bdescribes development of the APMP. For Tier 3 systems, the APMP requires
that supplemental treatment for nitrogen and/or pathogens must beused, based
on the source of impairment of the nearby water body. Supplemental treatment
classifies a system as a NOWTS, and requirements for NOWTS are described in
greater detail in Section 3.5 and Section 3.6, above.
Malibu Creek –TMDL with OWTS Allotment for Nitrogen:
Consideration of nitrogen impairment for Malibu Creek will be managed under the
TMDL implementation plan for Malibu Creek (USEPA, 2013) once a relevant
OWTS allotment for Domestic OWTS is defined by the RWQCB. TMDLs for
nitrogen have not yet been established for segments within the Malibu Creek
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Watershed. Appendix B provides information for determining whether a system
location is considered near to an impaired water body, including a map tool
provided by the SWRCB.
Table 4-2summarizesthe OWTS (septic systems) nitrogen allotment for Malibu
Creek, which includes domestic and commercial septic systems (USEPA, 2013).
The USEPA has defined an OWTS (septic systems) phosphorus allotment for
Malibu Creek as well (USEPA, 2013). The highest priority for implementation
actions for the septic systems category is to ensure that commercial septic
systems do not contribute to nutrient loading to the Malibu Lagoon subwatershed
area, specifically in the areas of the Malibu Colony Plaza, Cross Creek Plaza, and
Malibu Civic Center. These commercial systems may have been improperly sited
adjacent to the lagoon, in a groundwater table with historic levels that do not allow
as least 10 feet between the groundwater and septic system. Septic systems that
are poorly sited have options available for meeting the load allocations under the
TMDLs. One possible method of compliance is pretreatment via Nitrogen
Reduction Systems (NRS) of effluent to remove nutrients prior to leachfield
discharge (USEPA, 1999). The principal treatment mechanism for these systems
would be biological nitrification-denitrification. WDR permitting and permit limits
are the primary mechanism for the RWCB to enforce the load allocations for
commercial systems. See the individual TMDL implementation plan for detailed
requirements (USEPA, 2013).
Table 4-2 Summary of TMDL with OWTS Allotment for
Impaired Water Body -Malibu Creek
Source Existing % of Target Load
CategoryLoadsExisting Reduction Allocation
Load(%)
SUMMER:
Septic 91 pounds/day22%936 pounds/day
Systems
WINTER:
Septic 47,285 pounds 9%Not specified8 mg/L per
Systemsper 6 monthsday
4.3 Variances and Exceptions
Section 9.4 of the OWTS Policy identifies items that are not allowed to be managed
by a local agency. Prohibited items are summarized in Section 5.0 of this LAMP
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and no variance or exception will be granted by the DPH for new or
repair/replacement OWTS applications that include a prohibited item. Applicants
may be referred to the local RWQCB for further guidance and evaluation related
to items that the DPH are not allowed to manage, as applicable.
Applicants may make inquiries with the Chief of the Land Use Program. Decisions
by the Chief may be appealed to the Director of EH.
On a case-by-case basis, the Director may establish alternative siting and
operational requirements, where it is determined by the Director that the alternate
requirements will provide a similar level of protection against adverse impact to the
public water source and Public Health. Specific provisions for variances and
exceptions are summarized below.
New OWTS/NOWTS installations:
No part of a septic system shall be installed in an ingress/egress easement on a
private road intended to provide access to more than one property without a
variance from the DPH and written authorization from the local Fire Department.
When determined by the Department through adequate tests conducted by the QP
throughout the property that no favorable area for installation of the system is
available on the property, the Department may authorize the installation of the
system or part thereof in the easement.
A variance to specified horizontal setbacks may be permitted for lots created prior
to the effective date of the OWTS Policy (May 13, 2013) subject to meeting the
following requirements:
The septic tank and dispersal field shall be sited to comply with the horizontal
setback requirements to the maximum extent practicable;
The system shall incorporate supplemental treatment, including pathogen
removal;
Pathogen removal is defined as achieving an effluent fecal coliform bacteria
concentration less than or equal to 200 Most Probable Number (MPN) per 100
milliliters based on analysis of total coliform with a minimum detection limit of
2.2 MPN per 100 milliliters;
Minimum vertical separation to groundwater shall be two (2) feet below the
bottom of the dispersal field;
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The minimum dispersal field soil cover shall be 6 inches;
Other measures as specified by the Director, e.g., hydrological assessment,
are always required.
Repair/Replacement OWTS/NOWTS:
A variance to specified horizontal setbacks may be permittedfor
repair/replacement of an existing system subject to meeting the following
requirements:
-The dispersal field shall be sited to comply with the setback requirements
to the maximum extent practicable;
-The system shall a NOWTSor other mitigation measures specified by the
director, unless he/she finds no evidence of an existing or potential threat
of impact to the public water source by the system based on topography,
soil depth and groundwater conditions.
-Other measures as specified by the Director, e.g., hydrological assessment.
99
4.4Professional, Contractor and Maintenance Provider Qualifications
Table4-3. QualificationsforOWTSPractitioners
MinimumQC or QP
OWTSRequiredWorkProf.
Qualifications
ActivityGuide
Section(s)
Soil and Site Percolation testing, surface setbacks, and Chapter 2PG, CEG, PE,
Evaluations system design
PS/GE, REHS
and OWTS
Design,
except
as noted below
Subsurface ConductfieldstudiesandevaluateChapter 2PG, CEG
1
Explorationgeology,soils,percolation,groundwater,
slopesandother factors fordesign and
useofOWTS.
Geological Determination of uniform geology where Chapter 2PG
1
Assessmentextreme geologic conditions do not exist
1
Soil ProfilePrepare soil profile of any test pitsChapter 2PG, CEG
Slope Address potential slope destabilization for Chapter 2CEG, PS/GE
1
Evaluationproposed hillside installation
Hydrological Prepare/certify assessment to request Chapter 2PG, CEG, CHG
1
Assessmentwaiver of setback requirements from a
blue line stream/tributary and confirm the
dispersal system and drainage course will
not generate sufficient lateral infiltration to
negatively impact each other, declaring the
location for the proposed dispersal area
suitable
OWTS Install, All work related to install of new and Chapter 2General Building/
Repair or replaced OWTS, and repair of existing Engineering
ReplacementOWTSContractor License:
Class A, Class B,
Class C-42 or Class
C-36
Certification For purposes of certification inspection of Chapters 1 General Engineering
Inspection of existing OWTS, contractors who possess and 2Contractor License:
Existing only a General Building Contractor (Class Class A, Class C-42
OWTSB) license are not qualified to perform the or Class C-36
inspection
OWTS Aperson capable of operating, monitoring Chapters 5 Owner, manufacturer,
Operation, and maintaining an OWTS in accordance and 12or certified service
Monitoring, with LAMP and DPH requirements may provider, as
andperform these tasks (e.g., pumping).prescribed by the
MaintenanceDPH
101
1. The noted OWTS activity will be performed by a qualified professional on a specific site to
contribute to a feasibility report for installation of OWTS, as applicable.
CEG = California Certified Engineering Geologist; CHG = California Certified Hydrogeologist;
PE = California Professional Engineer; PG = California Professional Geologist; PS/GE =
California Professional Soil/Geotechnical Engineer; QC = Qualified Contractor (QC); QP =
Qualified Professional (QP), not employed by the County of Los Angeles; and REHS =
California Registered Environmental Health Specialist.
4.5 Education and Outreach
Los Angeles includes the following main sources for education and outreach
regarding OWTS:
Appendix Hof the County Plumbing Code. See Section 1.4 for a summary
of the relevant sections of the Plumbing Code.
Professional Guide. The Requirements and Procedures for Conventional and
Non-Conventional Onsite Wastewater Treatment Systems and Non-
Conventional Onsite Wastewater Treatment Systems Draftdated May 2016
(the “Professional Guide”) will be finalized upon approval of this LAMP and
incorporates provisions of the LAMP. See Section 1.5 for further description of
the content of the Professional Guide.
The final Professional Guide, as well as any substantive changes in the future will
require approval by the Director of EH and by the RWQCB. The DPH will make
every effort to notify the related industry and all interested parties of any revisions
to the Professional Guide 30 days prior to the effective date of the implementation.
A noticed hearing with opportunity for public comment must precede approval of
this LAMP by the RWQCB. The State Water Board shall then approve Local
Agency Management Programs at a regularly noticed board hearing and shall
provide for public participation, including notice and opportunity for public
comment.
The OWTS policy also requires notification to local water purveyors prior to local
OWTS permitting. The public water system owner shall have 15 days from receipt
of the permit application to provide recommendations and comments to DPH.
The DPH will make resources available on its website for individual homeowner’s
information
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4.6Septage Management
Septage is produced as a result of pumping the septic tank for an OWTS or
NOWTS during normal maintenance by the owner, in support of a real estate
transaction, or in support of repairs using a registered septic pumper and hauler.
Septic Pumpers and haulers are required to register with the local jurisdiction
(Health and Safety Code Section 117400-117450), which requires registration with
the Local Sanitation District in areas covered by this LAMP. Under normal
conditions, a properly sized tank can be expected to operate effectively for more
than five years without needing pumping (Bounds, 1997). The frequency of pump
out under normal conditions will vary depending on the size and hydraulic and
organic load handled by the tank.
Septage receiving facilities in Los Angeles County occur at the below waste water
treatment plants (WWTPs).
SouthCounty (Los Angeles RWQCB Region 4):
LA County –Pomona Liquid Waste Disposal Station, Pomona
LA County –Joint Water Pollution Control Plant, Carson
LA County –Saugus Water Reclamation Plant, Saugus
North County (Lahontan RWQCB Region 6):
LA County –Lancaster Water Reclamation Plant, Lancaster
The County Sanitation Districts of Los Angeles County tracks the volume of
septage processed at the above receiving facilities from both domestic and
commercial sources under their Liquid Waste Disposal Program and ensures that
capacities are adequate for the County’s septage generation. The current volumes
of waste received at the above facilities from septage sources are small relative to
the treatment and conveyance capacity at the facilities. No formal predictions for
future septage generation have been necessary, as the facilities could
accommodate a significant increase in the amounts of septage currently received
and capacity limitations have not been identified as a concern. Table 4-4presents
septagegeneration data from 2014 and 2015.
103
Table 4-4. Annual Septage Generation in Los Angeles County
Annual Septage Generation
Septage Receiving
(million gallons)
Facility
20142015
1
Pomona13.913.0
1
Carson18.621.1
1
Saugus4.35.0
1
Lancaster0.60.9
Total (Commercial and 37.440.0
1
Domestic)
Estimated Annual 16.216.2
Contribution from
Domestic
2
OWTS/NOWTS
Notes:
1. 2014 and 2015 Data Source: Annual Load, Volume and Receipt Reports,
Liquid Waste Disposal Program, January –December 2014 and January –
December 2015.2. Assuming an average pumping frequency of once every
five (5) years and a pump-out volume of 1,500 gallons per tank for the 53,148
OWTS and 813 NOWTS permitted in the County (as of January 28 2016),
the annual volume of septage generated by domestic OWTS and NOWTS in
the County was calculated. The estimated value of 16.2 million gallons per
year suggests the contribution from NOWTS and OWTS is approximately 40
to 43% of the total annual septage generated.
4.7Onsite Maintenance Districts
Currently Los Angeles County has not established onsite wastewater maintenance
districts or zones and no plans currently exist to establish them. It is unlikely that
a new district will be formed to oversee onsite maintenance for OWTS as the
Departments of Public Health and Building and Safety perform these duties.
4.8 Regional Salt and Nutrient Management Plans
Salt and Nutrient Management Plans (SNMPs) are required for each basin/sub-
basin in California in accordance with the SWRCB’s Recycled Water Policy, which
was adopted by the State Water Board through Resolution No. 2009-0011 on
February 3, 2009, and became effective on May 14, 2009. Per the Recycled Water
Policy, SNMPs will be developed by local water and wastewater entities, together
with localsalt/nutrient contributing stakeholders, through a locally driven and
controlled, collaborative process. It is the intent of the Recycled Water Policy that
salts and nutrients from all sources be managed on a basin-wide or watershed-
wide basis in a manner that ensures attainment of water quality objectives and
104
protection of groundwater's beneficial uses. The SNMP should be completed and
submitted to the Regional Water Board by May 2016.
Appendix B provides information for cumulative nitrate and salt loading from
OWTS in Los Angeles County, including methodology for estimating wastewater
discharge volumes, nitrate loading and salt loading contributions to groundwater
from OWTS. Estimates of nitrogen and salt loading will contribute to the program
level Regional SNMP efforts underway and headed up by the RWQCB in
conjunction with the stakeholders of the relevant groundwater basins. The DPH
will contribute to the planning efforts providing data and input regarding OWTS. In
Los Angeles County, Salt and Nutrient Management Plans developed or approved
by the RWQCB may support future Basin Plan amendments. The Salt and Nutrient
Management Planfor Antelope valley was completed May 2014.
4.9 Watershed Management Coordination
With thousands of permitted, as well as nonpoint source, discharges into the
receiving waters of the County, improving the water quality of the region’s
watersheds is a significant undertaking. The County Watershed Management
Division was established in August 2000 within the DPW to address the flood risk
management, water quality, water conservation, open space, and recreational
needs of the Los Angeles County Flood Control District. The DPW uses an
integrated, multipurpose approach that is consistent with watershed management
principles. These principles are carried out through a framework of collaboration
and partnerships, combined with sound science and local knowledge, as a
foundation for well-planned actions. Outcomes are monitored so that multi-
purpose projects may be adapted overtime to achieve improved results. The
Department of Water and Power and DPH are key county departments in
collaboration with DPW regarding watershed management issues. The county has
established programs that include an integrated regional watershed management
plan (IRWMP) for coastal watersheds, watershed management areas (WMAs),
and WPAs. Programs under the RWQCB (e.g., NPDES) augment the county’s
efforts for watershed management.
During preparation of this LAMP, the DPH collaborated with the DPW, industry
professionals, local authorities, stakeholders and the RWQCB for input into the
LAMP for regulations, policies and management issues. The DPH will continue to
work collaboratively to ensure adequate coordination regarding OWTS
considerations for watershed management. This LAMP and the OWTS policy
require adherence to OWTS prohibitions in Basin Plans and compliance with
TMDL implementation plans for the County, which help to responsibly manage
105
OWTS in local watersheds and near impaired water bodies. Under the provisions
of the newly formulated LAMP, the DPH anticipates increased collaboration with
the RWQCB for water quality assessment reporting under the LAMP.
4.10 Evaluating Proximity to Public Sewers
No plans will be accepted or approved for the installation, alteration, or repair of
any OWTS or part thereof, on any property for which a connection with a public
sewer is available within 200 feet. The public sewer may be considered as not
available when such public sewer or any building or exterior drainage facility
connected thereto is located more than 200 feet from any proposed building or
exterior drainage facility on any lot or premises that abuts and is served by such
public sewer. When a new dispersal system is required, the existing septic tank
should be replaced with a new tank unless it is certain that public sewer will be
available within two years.
This LAMP incorporates the following procedures for evaluating the proximity of
public sewer systems to new or replacement OWTS installations:
Chapter 1 of the Professional Guide informs permit applicants of the above
requirement to connect to public sewer if available within 200 feet.
Theproximity to public sewer must be included in the site evaluation.
DPH verify public sewerproximityduring the site evaluation process while
reviewing the permit application.
Buildingand Safety Department plan checks for building permits includes a
redundant verification of the proximityto public sewer priortoapproval.
4.11 OWTS Notification to Public Water System Owner(s)
Providing notice to public water system owners will be implemented as follows:
TheQPwillrelyupon informationprovidedbythe State Water Resources
Control Board (Division of Drinking Water) and by the DPH (Drinking Water
Program) todeterminethelocationand ownerof publicwaterwells or intake
locations during the site evaluation and permit application review. The location
of the public well or water system intake location may be verified during field
inspection.
106
If the OWTS is within 1,200 feet of an intake point for a surface water treatment
plant for drinking water, is in the drainage area catchment in which the intake
point is located, and is located such that it may impact water quality at the intake
point such as upstream of the intake point for a flowing water body, or if the
OWTS is within a horizontal sanitary setback from a public well, the OWTS
policy requires notification to local water purveyors prior to issuing an
installation or repair permit for an OWTS.Horizontal setbacks in the county
related to public wells are included in Table 3-4.
The public water system owner shall have 15 days from receipt of the permit
application to provide recommendations and comments to DPH.
DPH will review and consider any comments and recommendations received
from the public water system owner.
DPH will inform the public water system owner of the issuance or denial of the
permit application.
4.12 Policies and Procedures when a Proposed OWTS Dispersal Area is within
the Horizontal Sanitary Setback of a Public Well
A NOWTS including disinfection is required by DPH where a conventional OWTS
exists on a property and surfaceor subsurface water conditions are such that the
current setback requirements cannot be met. The following supplemental
treatment for nitrogen and pathogens are required by DPH to comply with the
OWTS Policy when a proposed OWTS dispersal area is within the horizontal
sanitary setback of a public well or a surface water intake point (10.9 and 10.10 of
the OWTS Policy):
Supplemental treatment requirements for nitrogen:
Effluent from the supplemental treatment components designed to reduce
nitrogen shall be certified by NSF, or other approved third party tester, to
meet a 50 percent reduction in total nitrogen when comparing the 30-day
average influent to the 30-day average effluent.
Where a drip-line dispersal system is used to enhance vegetative nitrogen
uptake, the dispersal system shall have at least six (6) inches of soil cover.
Supplemental treatment requirements for pathogens
Supplemental treatment components designed to perform disinfection shall
107
provide sufficient pretreatment of the wastewater so that effluent from the
supplemental treatment components does not exceed a 30-day average
TSS of 30 mg/L and shall further achieve an effluent fecal coliform bacteria
concentration less than or equal to 200 Most Probable Number (MPN) per
100 milliliters.
The minimum soil depth and the minimum depth to the anticipated highest
level of groundwater below the bottom of the dispersal system shall not be
less than three (3) feet. All dispersal systems shall have at least twelve (12)
inches of soil cover.
The above systems with supplemental treatment will be permitted as NOWTS.
4.13 Phase-Out of Cesspool Usage
Because the OWTS Policy does not allow cesspools to be managed by a local agency,
cesspoolusagewill be regulated by the Regional Water Quality Control Board.The
Regional Water Quality Control Board will allow the continued use of cesspools at
Single Family Dwellings(SFD) untilone of the following events happen:
The cesspool fails and must be replaced,
There is evidence that the cesspool is contaminating groundwateror surface
water, or
The homeowner obtains a permit to remodel their home in a manner that could
increase the wastewater flow, such as adding a bedroom.
The DPH will mandate septic tank pumping contractors to reportfailingcesspools to
DPH.
108
5.0 PROHIBITIONS
In Los Angeles County, when space is not available for a leach bed or leach line and
percolation test results for a seepage pit are slower than 0.83 gallons per square foot of
dispersal area per 24 hours, the property is not suitable for construction using either an
OWTS or NOWTS.
Section 9.4 of the OWTS Policy identifies items that are not allowed to be managed by a
local agency. The following items should be incorporated into the Los Angeles County
Code of Ordinances and the Professional Guide,as indicated below.
The County will phase out cesspool usage, which cannot be managed by a local
agency (OWTS Policy, Section 9.4.1). Phasing out of cesspool usage is described in
Section 4.13of this LAMP.
OWTS receiving a projected flow over 10,000 gallons per day are not managed by
DPH (OWTS Policy, 9.4.2).
OWTS that utilize any form of effluent disposal that discharges on or above the post
installation ground surface such as sprinklers, exposed drip lines, free-surface
wetlands, or a pond are not managed by DPH (OWTS Policy, 9.4.3).
A slope evaluation report is required where natural ground slopes in dispersal areas
are greater than 30 percent to address potential slope destabilization (OWTS Policy,
Section 9.4.4).
Leaching area for International Association of Plumbing and Mechanical Officials
(IAPMO) certified dispersal systems may not use a multiplier less than 0.70 (OWTS
Policy, Section 9.4.5).
OWTS utilizing supplemental treatment must have requirements for periodic
monitoring or inspections (OWTS Policy, Section 9.4.6), which is consistent with the
current Plumbing Code and Professional Guide.
OWTS must not receive significant amounts of waste dumped from RV holding tanks
such as at RV dump stations (OWTS Policy 9.4.7), which is consistent with the current
Plumbing Code and Professional Guide.
Separation from the bottom of the dispersal system to groundwater must not be less
than 2 feet for OWTS or less than 10 feet for seepage pits (OWTS Policy 9.4.8). The
County’s current Plumbing Code and Professional Guidemeet or exceed this
requirement for vertical separation. In Los Angeles County the separation from the
109
bottom of the dispersal system to groundwater must not be less than 5 feet for OWTS
without supplemental treatment, and must not be less than 10 feet for seepage pits.
Vertical separation in Los Angeles County is discussed in additional detail in Appendix
A.
The County’s current Plumbing Code and Professional Guideexceed the OWTS
Policy requirements prohibiting the installation of new or replacement OWTS where
public sewer is available (OWTS Policy 9.4.9). Specifically, in Los Angeles County no
plans will be accepted or approved for the installation, alteration, orrepair of any
OWTS or part thereof, on any property for which a connection with a public sewer is
available within 200 feet. In Los Angeles County, no exceptions are made for repair
or replacement OWTS based on cost considerations.
The OWTS Policy contains additional horizontal setback conditions that must be
amended to the Los Angeles County Code of Ordinances and that have been included
in the May 2016 Professional Guide (OWTS Policy 9.4.10). For new or replacement
OWTS where the depth of dispersal system does not exceed 10 feet, the OWTS must
be at least 150 feet from a public water well. If the depth of the effluent dispersal
system exceeds 10 feet in depth, the OWTS must be at least 200 feet from public
water well. If the depth of the effluent dispersal system exceeds 20 feet and is within
600 feet of a public water well, the setback must be such that there is at least two-
year travel time for microbiological contaminants. Horizontal setbacks in Los Angeles
County are discussed in additional detailin Appendix A.
Onacase-by-casebasis,thedirectormay establishalternativerequirementstothose
listedabovewhere it is determinedbythedirectorthatthealternaterequirementswill
provideasimilarlevelofprotection againstadverseimpacttothepublic watersource.
110
6.0 PROGRAM ADMINISTRATION
6.1 OWTS Permitting Records
The DPH will retain permanent records of OWTS permitting actions and will make
those records available within 10 working days upon written request for review by
either the Los Angeles or Lahontan RWQCB. This includes:
Installation approvalsissued for new, repair and replacement OWTS;
OWTS variances issued, including number, location and description; and
Operating permits issued for NOWTS.
6.2 Staffing of Land Use Program
Within the Environmental Health Division, the Land Use Program is responsible
for reviewing and approving plans for OWTS within designated cities and
unincorporated areas of the County of Los Angeles in an effort to protect
groundwater sources. Program personnel also inspect and permit sewage
pumping vehicles, chemical toilet pumping vehicles, and toilet rental agencies. In
addition, personnel are responsible for evaluating subdivision requests and
conducting environmental reviews within its scope.
The DPHwill ensure adequate staffing of the Land Use Program to oversee and
ensure proper implementation of this LAMP. Staff will be adequate to process
permit applications, engage the RWQCB when appropriate, maintain records,
update guidance/ordinance, and complete notification/reporting tasks.
6.3 Water Quality Assessment Program
The following sections present the general objectives and approach for the Water
Quality Assessment Program (WQAP). WQAP details are provided in Appendix B.
Objectives
The DPH will maintain an OWTS WQAP having three primary objectives: (1) to
determine the general operational status of OWTS within Los Angeles County’s
jurisdiction; (2) to assess and monitor possible impacts of OWTS on groundwater
and impaired surface waters and theirassociated beneficial uses; and (3) to
identify areas for changes to existing OWTS management practicesto improve
water quality from OWTS impacts.
111
Geographic Approach
It is anticipated that the GIS data will allow for the WQAP to be organized according
to various watersheds, groundwater sub-basins, U.S. Postal Service Zip Code
areas, or to delineated impaired water bodies for use in environmental studies and
the preparation of the Advanced Protection Management Program (APMP;
Appendix B). The WQAP will use GIS-based mapping, OWTS inventory, nitrate-
nitrogen data, and additional water quality assessment parameters to evaluate
potential OWTS impacts. In regions where the initial water quality assessment
determines that OWTS discharges may adversely affect groundwater and/or
surface water quality, additional parameters may be considered to determine
actual impacts of OWTS discharge. Other water quality assessment parameters
may include bacteria, total dissolved solids (TDS), chloride, sulfate, boron, and
various isotopes and anthropogenic chemicals as discussed in Appendix B. Other
localized focus areas can be delineated from the GIS and water quality
assessment parameters in the future if warranted.
OWTS Operational Status
The general operational status ofOWTS will be assessed through compilation and
review of the following types of information:
Septic tank pumper inspection reports;
Complaints and abatement activities for failing OWTS;
Variances issued for new and/or repair OWTS;
Performance inspections of existing OWTS in connection with building
additions/remodel projects, or property transactions;
Monitoring reports for alternative systems or other OWTS having an operating
permit.
The data review and assessment will focus on both positive and negative findings,
apparent trends, and areas for changes in practices. The assessment will maintain
and update the existing inventory of OWTS within Los Angeles County’s
jurisdiction.
Water Quality Assessment
The water quality assessment will include the following:
112
Water Quality Parameters of Concern. The initial focus of the water quality
assessment program will be on nitrate and fecal coliform bacteria. However,
in regions where the initial water quality assessment determines that OWTS
discharges may adverselyaffect groundwater and/or surface water quality,
additional parameters may be considered to determine actual impacts of
OWTS discharge.
Wastewater Discharge Volumes. Estimates of annual wastewater discharge
volumes from OWTS will be updated based upon the running inventory of
OWTS per above.
Nitrate Loading. Nitrate loading estimates (by watershed) will be maintained
and updated based on the running inventory of OWTS in the County.
Water Quality Data Sources. Relevant water quality monitoring data for
(pathogens, nitrate-nitrogen and TDS) will be compiled from available sources,
anticipated to include:
Water quality data from cumulative impact studies;
Los Angeles County Waterworks Districts (LACWD) Annual Water Quality
Reports;
Domestic water wells sampling from new wells or other;
Public water system raw water quality data monitoring reports;
Reservoir or stream water quality sampling data from available watershed
special studies;
Receiving water sampling performed as part of an NPDES permit;
Groundwater sampling performed as part of Waste Discharge
Requirements;
Groundwater data collected as part of Salt and Nutrient Management Plans
Data from the California Water Quality Assessment Database; and
Groundwater data collected as part of the Groundwater Ambient Monitoring
and Assessment Program available in the Geotracker Database.
Assessment. In addition to periodically updating loading estimates for OWTS
water quality assessment parameters within the County, it is anticipated that data
113
assessment will include a review that is designed to: (a) determine relevance of
the various data to OWTS; (b) identify any likely water quality degradation
attributable to OWTS; (c) identify changes to the LAMP undertaken to address
impacts from the OWTS.
The laboratory analytical protocol for bacteria assessment will use the Most
Probable Number (MPN) for the determination of totalcoliforms.
6.4 Reporting to RWQCBs
The following will be provided to theRWQCB in the annual report.
Annual Report
An annual report pertaining to OWTS activities in Los Angeles County for
submission to the Los Angeles RWQCB by February 1st of each year, with a copy
also sent to the Lahontan RWQCB. The annual report will, at a minimum, include
the following information, organized in a tabular spreadsheet format:
Number and location of complaints pertaining to OWTS operation and
maintenance, and identifying those which were investigated and how they were
resolved;
Number, location and description of permits issued for new and replacement
OWTS, including any variances issued;
Results of NOWTS inspections and effluent testing completed;
Any enforcement actions including permit suspension or revocations, referrals
to the District or City Attorney for prosecution, and referrals to the Regional
Water Quality Control Board to submit a Report of Waste Discharge due to non-
compliance.
Results of septictank pumper inspection reports and where excessive pumping
is occurring;
Numberand location of known cesspoolsin the Los Angeles County;
List of applications and registrations issued as part of the local septic tank
pumper registration program pursuant to Section 117400 et seq. of the
California Health and Safety Code;
Water quality data collected from sources identified above.
114
The report will include: (a) a summary of whether any further actions related to
OWTS are warranted to protect water quality or public health; and (b) any other
information deemed appropriate by the Director of Environmental Health.
5-Year Water Quality Assessment Report to RWQCB
Every five (5) years the annual report to the RWQCB will be accompanied by a
Water Quality Assessment Report that summarizes the information and findings
from the DPH Water Quality Assessment Program described under heading 2 for
the Annual Report. The 5-year report will present an overall assessment regarding
any evidence of water quality impact from OWTS along with any recommended
changes in the LAMP designed to address the identified impacts.The County will
utilize existing data to create a baseline assessment, and thereafter, will collect
data annually to assess changes.Appendix B provides additional discussion of
assessment related to OWTS. Additionally, any groundwater water quality data
generated by the DPH from monitoring activities will be submitted for inclusion in
Geotracker.
115
7.0 REFERENCES
Bounds, T.R., Design and Performance of Septic Tanks, Site Characterization and
Design of Onsite Septic Systems, ASTM STP 901, M.S. Beginger, A.I. Johnson,
and J.S. Fleming, Eds, American Society of Testing Materials, Philadelphia, 1997.
California Department of Water Resources, UST -Depth to Groundwater Database,
http://www.waterboards.ca.gov/losangeles/water_issues/programs/ust/groundwat
er_database.shtml, Accessed between January 2016 and April 2016.
California Department of Water Resources, Water Data Library (WDL),
http://www.water.ca.gov/waterdatalibrary/, Accessed between January 2016 and
April 2016.
California Health & Safety Code, §§ 116275; 116500.
Clean Water Act Section 303(d) Listed Impaired Waters and Total Maximum Daily Loads
(TMDLs), Accessed between January 2016 and April 2016.
Lahontan Region, North and South Basins -California Regional Water Quality Control
Board, Water Quality Control Plan for the Lahontan Region, March 31, 1995,
amendments effective August 1995 through September 10, 2015.
Los Angeles County, Department of Public Health (DPH), Environmental Health, Bureau of
Environmental Protection, Land Use Program, Requirements and Procedures for
Conventional and Non-Conventional Onsite Wastewater Treatment Systems, the
Professional Guide, DRAFT dated May 2016.
Los Angeles County, Department of Public Health (DPH), Environmental Health, Land Use
Program, Guidelines: Approval of Non-Conventional Onsite Wastewater Treatment
Systems (NOWTS), Revised –Effective December 1, 2014.
Los Angeles County, Department of Public Health (DPH), Environmental Health, Bureau of
Environmental Protection, Land Use Program, A Professional Guide to
Requirements and Procedures for Onsite Wastewater Treatment Systems (OWTS),
November 1, 2013.
Los Angeles County, Department of Public Works (DPW),Depth to Groundwater
Database, http://dpw.lacounty.gov/general/wells/, Accessed between January
2016 and April 2016.
Los Angeles County, Department of Public Works (DPW), Hydrology Manual, Water
Resources Division, January 2006.
Los Angeles County Code,Title 28 Plumbing Code,
https://www.municode.com/library/ca/los_angeles_county/codes/code_of_ordina
nces?nodeId=TIT28PLCO_CH1AD, Accessed between January 2016 and April
2016.
116
Los Angeles County, Department of Public Works Waterworks District No. 40, Los
Angeles County, Sanitation Districts Nos. 14 and 20 and AntelopeValley Salt and
Nutrient Management Planning Stakeholders Group, Salt and Nutrient
Management Plan (SNMP) for the Antelope Valley, May 2014.
Los Angeles Region –California Regional Water Quality Control Board, Resolution No.
R14-007, Amendments to the Water Quality Control Plan for the Los Angeles
Region to incorporate the State Water Quality Control Policy for Siting, Design,
Operation and Maintenance of Onsite Wastewater Treatment Systems,May 8,
2014.
Musgrave, G. W., How much of the rain enters the soil, Water Yearbook of Agriculture. U.S.
Department of Agriculture. Washington, DC. pp. 151-159, 1955.
Natural Resources Conservation Service (NRCS), Soils, NRCS Webpage Providing Links
to Field Office Technical Guide (FOTG), Web Soil Survey, and Soil Data
http://www.nrcs.usda.gov/wps/portal/nrcs/site/soils/home/, Accessed between
January 2016 and April 2016.
Sanitation Districts of Los Angeles County, Wastewater Ordinance,
www.lacsd.org/wastewater/industrial_waste/iwordinances/wastewater_ordinance.a
sp, April 1,1972, as amended July 1, 1998.
State Water Resources Control Board (SWRCB), 2012, OWTS Policy, Water Quality
Control Policy for Siting, Design, Operation, and Maintenance of Onsite Wastewater
Treatment Systems, formerly known as Assembly Bill 885, adopted by the SWRCB
on June 19, 2012, approved by the Office of Administrative Law on November 13,
2012, effective date of the policy is May 13, 2013.
United States Census Bureau, Los AngelesCounty, California, State & County Quick
Facts, http://www.census.gov/quickfacts/#table/PST045215/06037, Accessed
January 21, 2016.
United States Department of Agriculture, National Resource Conservation Service,
National Engineering Handbook (NEH), Part 630, Chapter 7, Hydrologic Soil
Groups; 210–VI–NEH, Issued January 2009.
United States Environmental Protection Agency, Onsite Wastewater Treatment Systems
Manual. (EPA/625/R-00/008), Office of Water, Office of Research and
Development. Washington, DC, February 2002.
United States Environmental Protection Agency, The Class V Underground injection Well
Control Study, Volume 5, large capacity Septic Systems, 1999.
United States Environmental Protection Agency, Region 9, Total Maximum Daily Loads
for NutrientsMalibu Creek Watershed, EPA-Established TMDL, 2013.
University of California Los Angeles Institute of the Environment and Sustainability,
117
Southern California Environmental Report Card,
http://www.environment.ucla.edu/reportcard/article4870.html, Fall 2009.
118
AppendixA
Los Angeles County
Supporting Rationalefor
OWTSSitingandDesign Criteria
SUPPORTINGRATIONALEFOR
LOS ANGELES COUNTYOWTSSITINGANDDESIGNCRITERIA
Appendix A is a discussion of siting and design requirements for OWTS within Los
Angeles County that differ from SWRCB Tier 1 requirements. The topics in this appendix
include: (1) Los Angeles County LAMP Tier 2 Variations from SWRCB OWTS Tier 1
Requirements; (2) OWTS Policy Items That Are Not Allowed to be Managed in a LAMP;
(3) Tier 4 OWTS Requiring Corrective Action; (4) Los Angeles County’s Tier 2 OWTS
vertical separation from groundwater and the use and requirements on Seepage Pits,
Infiltrative Chambers, and Gravel-Packed Pits; (5) Subdivision densities; (6) NOWTS (7)
dispersal system sizing methodology; and (8) horizontal setbacks.
Appendix B addresses the Water Quality Assessment Program (WQAP) for identifying
Tier 0 (existing OWTS) that are determined to be contributing to an impaired surface
water body listed in Attachment 2 of the SWRCB OWTS Policy, and for developing an
Advanced Protection Management Program (APMP) for these OWTS.
A-1.Los Angeles County LAMP Tier 2 Variations from SWRCB OWTS Tier 1
Requirements
There are no key issues related to Los Angeles County’s LAMP Tier 2 OWTS variations
relative to SWRCB Tier 1 requirements. County Tier 2 requirements are as stringent in
the protection of public health and of the environment as SWRCB Tier 1 requirements.
However, the County’s LAMP will need to adopt some horizontal setback minimums not
currently specified in the County’s plumbing code (see Section A-4).
Los Angeles County’s LAMP Tier 2 OWTS vertical separation from groundwater
requirements are listed in Table A-1. Table A-1 also provides the depth to groundwater
from historical guidelines of the South Lahontan and Los Angeles RWQCB, and the Tier
1 requirements in the SWRCB OWTS Policy. As indicated in Table A-1, the adopted
minimum depth to groundwater and the required soil percolation rate shows the County
requirements for conventional OWTS.
A-2.OWTS Policy Items That Are Not Allowed to be Managed in a LAMP
Section 9.4 of the OWTS Policy identifies items that are not allowed to be managed by a
local agency. The following items should be incorporated into the Los Angeles County
Code of Ordinances and the Professional Guide,as indicated below.
The County will phase out cesspool usage, which cannot be managed by a local
agency (OWTS Policy, Section 9.4.1). Phasing out of cesspool usage is described in
Section 4.13 of this LAMP.
OWTS receiving a projected flow over 10,000 gallons per day are not managed by
DPH (OWTS Policy, 9.4.2).
OWTS that utilize any form of effluent disposal that discharges on or above the post
installation ground surface such as sprinklers, exposed drip lines, free-surface
wetlands, or a pond are not managed by DPH (OWTS Policy, 9.4.3).
A slope evaluation report is required where natural ground slopes in dispersal areas
are greater than 30 percent to address potential slope destabilization (OWTS Policy,
Section 9.4.4).
Leaching area for International Association of Plumbing and Mechanical Officials
(IAPMO) certified dispersal systems may not use a multiplier less than 0.70 (OWTS
Policy, Section 9.4.5).
OWTS utilizing supplemental treatment must have requirements for periodic
monitoring or inspections (OWTS Policy, Section 9.4.6), which is consistent with the
current Plumbing Code and Professional Guide.
OWTS must not receive significant amounts of waste dumped from RV holding tanks
such as at RV dump stations (OWTS Policy 9.4.7), which is consistent with the current
Plumbing Code and Professional Guide.
Separation from the bottom of the dispersal system to groundwater must not be
less than 2 feet for OWTS or less than 10 feet for seepage pits (OWTS Policy
9.4.8). The County’s current Plumbing Code and Professional Guidemeet or
exceed this requirement for vertical separation. In Los Angeles County, the
separation from the bottom of the dispersal system to groundwater must not be
less than 5 feet for OWTS without supplemental treatment, and must not be less
than 10 feet for seepage pits.
The County’s current Plumbing Code and Professional Guideexceed the OWTS
Policy requirements prohibiting the installation of new or replacement OWTS where
public sewer is available (OWTS Policy 9.4.9). Specifically, in Los Angeles County no
plans will be accepted or approved for the installation, alteration, or repair of any
OWTS or part thereof, on any property for which a connection with a public sewer is
available within 200 feet. In Los Angeles County, no exceptions are made for repair
or replacement OWTS based on cost considerations.
The OWTS Policy contains additional horizontal setback conditions that must be
amended to the Los Angeles County Code of Ordinances and that have been included
in the May 2016 Professional Guide (OWTS Policy 9.4.10). For new or replacement
OWTS where the depth of dispersal system does not exceed 10 feet, the OWTS must
be at least 150 feet from a public water well. If the depth of the effluent dispersal
system exceeds 10 feet in depth, the OWTS must be at least 200 feet from a public
water well. If the depth of the effluent dispersal system exceeds 20 feet and is within
600 feet of a public water well, the setback must be such that there is at least two-
year travel time for microbiological contaminants.
A-3.Tier 4 OWTS Requiring Corrective Action
OWTS that require corrective action, are presently failing, or that fail while this LAMP is
in effect are automatically included in Tier 4. OWTS included in Tier 4 are subject to the
following requirements (OWTS Policy, Section 11):
If the OWTS dispersal system is no longer adequately percolating effluent such that
there is pooling effluent, discharges of wastewater to the surface, or wastewater has
backed up into plumbing fixtures, the dispersal system must be replaced, repaired, or
modified so as to return it to its proper function and comply with Tier 1, 2 or 3.
Any OWTS septic tank failure such that wastewater is exfiltrating or groundwater is
infiltrating shall be repaired to bring the tank into compliance with the requirements of
the appropriate OWTS Tier.
Any other OWTS component failure shall be repaired so as to return the OWTS to
proper functioning condition and return the OWTS to Tier 1, 2, or 3.
Any OWTS that has affected or will affect groundwater or surface water to a degree
thatmakes it unfit for drinking or other uses, or is causing a human health condition
or other public nuisance shall be modified or upgraded to abate its impact.
Owners of OWTS included in Tier 4 will complete any corrective action as directed by
the Health Officer. Owners of a perceived failed system will be directed to have their
system evaluated to determine whether it has failed and the reason for the failure.
Owners of failed OWTS will complete and submit an application form to the DPH in
accordance with the Professional Guide. If the owner is unable to comply with the
corrective requirements of Tier 4, the RWQCB may authorize repairs that are in
substantial conformance, to the greatest extent possible, with Tier 1 or Tier 3.
Alternatively, the RWQCB may require the owner to submit a report of waste
discharge for evaluation on a case-by-case basis. Where appropriate, the DPH may
authorize repairs that are in substantial conformance, to the greatest extent possible,
with Tier 2. Failure to meet the requirements of Tier 4 is subject to further enforcement
action.
Owners of failing OWTS will address any corrective action requirements in
compliance, and must comply with a time schedule of any corrective action notice
received from the DPH or RWQCB, to retain coverage under this LAMP.
Failure to meet the requirements of Tier 4 constitute a failure to meet the conditions
of the waiver of waste discharge requirements contained in this LAMP, and are subject
to further enforcement actions.
A-4.Los Angeles County’sTier 2 OWTS Vertical Separation from Groundwater
and the Use and Requirements on Seepage Pits, Infiltrative Chambers, and
Gravel-Packed Pits
TABLEA-1
Comparison of Depth to Groundwater Requirements for OWTS
with Leach Line, Leach Field or Infiltrative Chamber Dispersal
Systems.(feet,belowtrenchbottom)
PercolationLos Angeles South Los Angeles SWRCBOWTS
RateCounty LahontanRWQCB PolicyTier1
LAMP and RWQCB GuidelinesRequirements
(minper
Plumbing Guidelines
inch)
Code
<520202020
5-605---
>60Not Allowed---
6-30-888
31-120-555
Table A-1shows the proposed depth to groundwater requirements for Los Angeles
County under the Tier 2 LAMP. Under the OWTS Policy (Section 9.4.8), the minimum
separation from the bottom of the dispersal system to groundwater must be at least 5 feet
for OWTSwith percolation rates between 5 –60 MPI,20 feet for conventional OWTS with
percolation rates of 1 -<5 MPI,2 feet for NOWTS with pressurized drip dispersal systems,
and 10 feet for seepage pits; the proposed depth to groundwater requirements for the
Tier 2 LAMP are in compliance with the minimum separation required in the OWTS Policy,
but differ from Tier 1 between 6 and 30 MPIas shown in Table A-1.
Los Angeles Countydoes not allowfor reducedgroundwaterseparationdistances based
on percolation rates, but does allow fornon-conventional OWTS (NOWTS) dispersal
systemsasshowninTable A-2. Table A-2 provides NOWTS dispersal systems
requirements, which are presented in detail in the following sections.
TABLEA-2
Los Angeles CountyDepthtoGroundwater
RequirementsforOWTSandNOWTS
Min.Depthto
1
PercolationRateGroundwater(feet)
TypeofOWTS
ConventionalSepticTank,leach line,
20
1-<5
leach field orinfiltrative chambers
ConventionalSepticTank,leach line, 5-605
leach field orinfiltrative chambers
NOWTS with leach line, leach field, or 1-603
infiltrative chambers
Between 0.83 and
Seepage Pits, and Gravel-Packed Pits5.12 gallons per
square foot in 24 10
hours
Seepage Pits and Gravel-Packed Greater than 5.12
Pits –With NOWTS and gallons per square
foot in 24 hours
disinfection system.10
Soil Replacement: the Greater than 5.12 2ft as a variance for
manufactured/engineered soil shall gallons per square existing systems only.
provide homogenized absorption foot in 24 hours Otherwise, 5 ft.
capability, requires the use of a
NOWTS system that uses
pressurized drip tubing or other
non-conventional method of
1
Measured fromthebottomof thedispersalsystem
A-5.Subdivision Densities
The average density for any subdivision of property made by Tentative Approval pursuant
to the Subdivision Map Act implemented under this Tier 2 LAMP shall not exceed the
allowable OWTS density values in Table A-3 for a single-family dwelling unit, or its
equivalent, for those parcels that rely on OWTS. The County will amend the Los Angeles
County Code of Ordinances to include the allowable average densities per subdivision
requirements, which will be applicable to Conditional Use Permit and land Subdivision
projects.
Exception to the subdivision densities requirements may be granted if an NOWTS is
proposed.
Lots created prior to the implementation of this LAMP are not subject to the
aforementioned minimum lot size requirements, however they willbe subject to the design
requirements of this LAMP.
Existing lots in the Antelope Valley area under the authority of the Lahontan Water Board
are subject to the limitation of 1 single family residence per half acre,or a maximum parcel
loading rate of 500 gal/(acre/day)that was in effect prior to the adoption of the LAMP.
Figure 2-4includes a map of average annual rainfall for the geographic regions in the
County.
TABLEA-3
Allowable Average Densities per Subdivision
Average Annual Rainfall (in/yr)Allowable Density
(acres/single family dwelling
unit)
0-152.5
>15 -202
>20 -251.5
>25 -351
>35 -400.75
>400.5
A-6.NOWTS
Thesupportingrationalefor the NOWTS dispersal systems are presented below.
Supplemental Treatment
NOWTS are required under these conditions:
Where percolation rates are too fast or too slow. Specifically, where the percolation
rate exceeds 5.12 gallons per square foot of dispersal area per 24 hours, or where the
percolation rate is faster than 5 minutes per inchwithout 20 feet separation to
groundwateror is slower than 60 minutes per inch for a new or replacement OWTS.
For seepage pits at existing construction with an absorption rate faster than 5.12
gallons per square foot of dispersal area,
For new constructionwith flows larger than a 4 bedroom houseusing seepage pits,
For systems under Tier 3 regulation near impaired water bodies requiring
supplemental treatment under the APMP,
For insufficient depth of undisturbed soil depth between leach lines and bedrock,
There is less than three (3) feet of continuous, natural, undisturbed soil beneath an
existing, new or replacement conventional dispersal system,
For retrofit of an existing system where setbacks cannot be met,
The property of the proposed system is within the 600 feet boundary of an impaired
water body that is listed for pathogens or nitrogen and no TMDL implementation plan
with OWTS allotment has been established,
For areas where the groundwater is known to have high level of nitrogen or pathogens
and that can be attributed to high density of OWTS.
The property lies within an area covered by a TMDL implementation plan with OWTS
allotment that requires supplemental treatment for OWTS <10,000 GPD \[Note that it
is possible that OWTS <10,000 GPD may not be required to include supplemental
treatment in every TMDL implementation plan\], and
The future expansion area requirements cannot be met.
Allsupplementaltreatmentsystemsandcomponentsshallbeinstalledandoperated
inaccordancewiththeirrespectivemanufacturers’recommendationandaresubject
toreviewandacceptancebytheDPH. Acceptanceofsupplementaltreatment
systemsbytheDPHiscontingentuponademonstrationthroughextensivefieldand
testdataconfirmingthatthesupplementaltreatmentsystemwillproducecontinuous
andlong-rangeresults.Thisacceptanceissubjecttorevocationwhenthe
supplementaltreatmentsystemisdeemedinadequate bythe DPH.
Thesupplementaltreatmenttechnologybeingdemonstratedshallmeetorexceed
secondarytreatmentstandardsandshallprovidereductioninBiochemicalor
CarbonaceousBiochemicalOxygenDemand(BOD/CBOD),TotalSuspendedSolids
(TSS)concentrationsandTotalNitrogenasprescribedfurther.
The following requirements shall apply to Supplemental Treatment Units:
Systems must be NSF 245 certified or pass a demonstration test, unless they are
installed for bacteriological reduction as a result of Tier 3 requirements. If the systems
are only required to treat for bacteria, the systems must be NSF 40 certified or pass
a demonstration test.
For disinfection, the State OWTS Policy requires that supplemental treatment
components be designed to provide sufficient pretreatment of the wastewater so that
effluent from the supplemental treatment components does not exceed a 30-day
average TSS of 30 mg/L and shall further achieve an effluent fecal coliform bacteria
concentration less than or equal to 200 Most Probable Number (MPN) per 100
milliliters.
Tanks must be IAPMO or similarly certified.
Supplementaltreatmentcomponents,otherthanthatofdisinfection,shallbe
designedtoreducetheconcentrationofBOD/CBOD,TSS andTotal Nitrogen(TN).
Supplementaltreatmentcomponents,otherthanthatofdisinfection,shallproduce
aneffluentconcentrationlevelthatmeetsorsurpassesthefollowing requirements:
-BOD –30 mg/L or CBOD5 –25 mg/L
-TSS –30 mg/L
-Total Nitrogen –At least a 50% average reduction of influent (Total Nitrogen)
-pH –6.0 to 9.0 SU
NOWTSshallbeequippedwithavisualoraudiblealarmaswellasatelemetric
alarmthatnotifiestheownerandtheserviceprovideroftheNOWTSintheeventof
systemmalfunction. Thetelemetricmonitoringsystemshallbecapableof
continuouslyassessing the operationofthesupplementaltreatmentsystem. The
owner must enter a covenant with the County prior to approval of the system.
NOWTSwithsupplementalcomponentsshallbemonitoredbyaserviceproviderwho
iscertifiedbythecomponents’manufacturerandmaintainstheNOWTSin
accordancewiththeoperationandmaintenancemanualforthecomponentsandas
prescribedbytheDPH.TheNOWTSdesignedtomeetthetreatmentperformance
requirementsoutlinedaboveshallbeinspectedbytheserviceproviderasfrequently
as neededor morefrequently asrequiredbythe DPH toensureproperoperationat
alltimes. Thereportsofallmaintenancerecordsshallbeforwardedtothe DPHon
aquarterlybasisormorefrequentlyasdeemedbythe DPH.
Annual effluent testing will be required for NOWTS installed in the portion of the
Antelope Valley regulated by the Lahontan Regional Water Quality Control Board at a
commercial, industrial or institutional setting only.
NOWTS installed to meet the supplemental treatment requirements for pathogens in
Tier 3 water body impaired or TMDL areas shall be subject to quarterly effluent testing.
Effluent samples shall be taken by service provider under contract at the point of
discharge; the sample shall then be taken to a ELAP certified laboratory for such
analysis. The results of the laboratory analysis shall be forwarded to DPH. The lab
report shall clearly specify the location/address where sample was taken from. The
laboratory analysis must include TSS. The bacteriological analysis shall consist of the
totalcoliform bacteria. The lab results must confirm that the supplemental treatment
water quality and bacteriological standards described above are met.
NOWTS owners withsupplemental treatment components must enter into an
agreement with the County prior to approval of their systems.
NOWTS owners are required to obtain an annual public health permit upon the
certificate of occupancy being issued by building and safety.
Thedataprovided inmonitoringlaboratory analysis reports are subject toverification by
the DPH.
Note: TheDPHmayexercisetheoptionofrequiringsamplestobetakenwhileaDPH
representativeispresentand/orbyanindependentpartyauthorizedbytheDPH.
Additionalrequirementstoensureproper“ChainofCustody” shallapply.
Soil Replacement
Forthepurposesofthisdocument,soilmeansthenaturallyoccurringbodyof
porousmineralandorganicmaterialsonthelandsurface,whichiscomposedof
unconsolidatedmaterials,includingsand,silt,andclayparticlesmixedwithvarying
amountsoffragmentsandorganicmaterial.
Whereundisturbedearthhasinsufficientdepthtosatisfytheminimumdepth
requirementsorhaspoorabsorptionrate,manufactured/engineeredsoilwithsimilar
compositioncharacteristicsofloamysand,certifiedbyaCaliforniaRegistered
ProfessionalSoil/GeotechnicalEngineer,maybeaddedtothe existingnative soilso
thatthesiteconditionsmeetorexceedthespecificdepthandabsorptionrate
requirements.Themanufactured/engineeredsoilshallbere-composedandre-graded
uniformlytoprovidehomogenizedabsorptioncapability,equivalenttosoilcategoryof
loamysand.Thequalifiedprofessionalshallprovethroughsieveanalysisandother
quantifyingteststhatthedesirablecompositionandcompactionhasbeenachieved.
Thecompactioncharacteristicsofthemanufacturedsoilshallcorrespondasclose
aspossibletothenativesoilofthesurroundingarea. Adequatenumberof
percolationtestsshallbeconductedintheareawheremanufacturedsoilhasbeen
providedtoconfirmthatthepercolationratesareincorrelationwithloamysandsoil
category.Theresultsofthepercolationtestsconductedinthearea shall affirm
uniformityin soilcomposition and compaction.
Additional requirements:
Apressurizeddistributionsystemisrequiredwhereengineeredsoilisusedin
ordertocomplywiththeminimumsoildepthand/ortheabsorptionrate
requirements.Pressurizeddistributionmeansatypeofdispersalsystemthat
employsapumpanddistributionpipingwithsmalldiameterperforation(1/4ofan
inchorless)ordripemittersthatareinstalledatadepthof6inches(Tier 1
requirement) belowgradeandaminimumof6inchesapartorasrecommended
bythemanufacturerandapprovedbythe DPH,todistribute effluentintosoilwith
uniformdistribution.
Soilreplacementshallnotcompromisetheprotectionofthegroundwater;a
minimumof5feetofseparationtogroundwater from the lowest point of the dispersal
systemshall be allowedand a minimum of 2 feet for replacement systems
Percolationtestingshallbedoneinthoseareaswhereengineeredsoilhasbeen
providedtoensurethatnewsoilmeetsorexceedstheabsorptionrate
requirements.
Engineeredsoilshallcompensateforthelackofin-placesoilataratioof1.5to1;
sothata1footdeficiencyinthesoilcolumndepthwouldrequire1.5feetof
engineeredsoilmaterial. Innocaseshallengineeredsoilcompensateformore
than2feetoftheminimumnativesoildepthrequirements.
Asiteevaluationshalldeterminethata minimum of 3 feetsoildepthispresentinthe
dispersalarea.Soil depthis measuredvertically to the point where bedrock, hardpan,
or impermeable soilsareencounteredoranadequatedepththathasbeendetermined
bytheDPH.Soildepthshallbedeterminedthroughtheuseofsoilprofile(s)inthe
dispersalareaandthedesignateddispersalsystemreplacementarea,asviewedin
excavationsexposingthesoilprofilesinrepresentativeareas,unlesstheDPHhas
determinedthroughhistoricalor regional informationthata specific site soil profile
evaluation is unwarranted.
A-7.Dispersal System Sizing Methodology
Dispersalsizing required by the SWRCB OWTS Policy uses the maximum application
rate determined from stabilized percolation rates provided in Table 3 of the OWTS Policy,
or from soil textures and structures determined in Table 4 of the OWTS Policy. This
LAMP utilizes the Ryon Formula and actual system testing to insure an appropriate
disposal system sizing for the local soil conditions.
The Ryon Formula is as follows:
WhereA = Squarefeetof3-footwidetrench
dispersalarea
th
T =Time in minutesfor the6inchofwater
to drain
C =Proposedseptic tankcapacity
The resulting “A” must be divided by 3 to arrive at the length of a 3 foot widetrench with
1 foot of filter material below the perforated pipe provided for the dispersal system. For
trenches proposing 2 feet of filter material below the pipe, “A” must be divided by 5 to
arrive at the length of trench. For trenches proposing 3 feetof filter material below the
pipe, “A” must be divided by 7.
thth
Absorption rates faster than 60 minutes for the water level to drop from the 5to 6inch
do not meet the minimum requirements. Conversely, absorption rates of faster than 5
thth
minutes for the water to drop from the 5to 6inch shall not be accepted and will require
Supplemental Treatment. OWTS with nonconforming absorption rates are required to
either replace the native soil for absorption rates slower than 60 MPI, or provide
supplemental treatment of the sewage effluent prior to discharging into the receiving
environment below ground surface for absorption rates faster than 5 MPI.
A-8.Horizontal Setbacks
The location of OWTS components is regulated by the SWRCB Policy and is dependent
upon horizontal distance from specific characteristics susceptible to contamination
effects. Similar horizontal setback requirements have been established in Los Angeles
County and are found in Table K-1 in Appendix K of the Plumbing Code of Ordinances.
Although County Ordinances require different setback distances depending on the OWTS
component under consideration, Tier 2 requirements may not be any less stringent than
those for Tier 1 established by the SWRCB. Horizontal setback distances currently
required by the County are as follows:
TABLEA-4
Current Location of Sewage Disposal System Requirements from the Plumbing
Code
Minimum Horizontal Distance Disposal
Septic TankSeepage Pit
in Clear Required From:Field
1
Buildings or Structures5 feet (1.52 m)8 feet (2.44 m)8 feet (2.44 m)
Property line adjoining private
5 feet (1.52 m)5 feet (1.52 m)8 feet (2.44 m)
property
50 feet (15.24 100feet
8
Water supply wells150 feet (45.7m)
m)(30.5m)
77
Streams and other bodies of 50 feet (15.24 100 feet150 feet(45.7
8
waterm)(30.5m) m)
Trees10 feet (3.05 m)—10 feet (3.05 m)
Seepage pits5 feet (1.52 m)5 feet (1.52 m)12 feet (3.66 m)
4
4 feet(1.22
Disposal field5 feet (1.52 m)5 feet (1.52 m)
m)
On site domestic water service
5 feet (1.52 m)5 feet (1.52 m)5 feet (1.52 m)
line
Distribution box—5 feet (1.52 m)5 feet (1.52 m)
10 feet (3.05
Pressure public water main10 feet (3.05 m)10 feet (3.05 m)
m)
Note:
When disposal fields and/or seepage pits are installed in sloping ground, the minimum
horizontal distance between any part of the leaching system and ground surface shall
be fifteen (15) feet (4.57 m).
1.Including decks, patios, porches and steps, whether covered or uncovered,
breezeways, roofed porte-cocheres, roofed patios, carports, covered walks, covered
driveways and similar structures or appurtenances.
2.Reserved.
3.Reserved.
4.Plus two (2) feet (610 mm) for each additional (1) foot (3.05 m) of depth in excess of
one (1) foot (3.05 m) below the bottom of the drain line. (See also Section K 6 in
Appendix K of the Plumbing Code.)
5.Reserved.
6.For parallel construction—For crossings, approval by the Health Department shall be
required.
7.These minimum clear horizontal distances shall also apply between disposal field,
seepage pits, and the ocean mean higher high tide line.
8.Where special hazards are involved, the distance required shall be increased as may
be directed by the Authority Having Jurisdiction.
The SWRCB OWTS Policy contains the following horizontal setback conditions for OWTS
treatment components and dispersal systems to be located a minimum of:
5 feet from parcel property lines and structures (OWTS Policy Section 7.5.1) \[The
Plumbing Code currently meets or exceeds this requirement\].
100 feet from private water wells and monitoring wells, unless regulatory or legitimate
data requirements necessitate that monitoring wells be located closer (OWTS Policy
Section 7.5.2) \[Must be amended to the Los Angeles County Code of Ordinances\].
100 feet from any unstable land mass or any areas subject to earth slides identified
by a registered engineer or registered geologist; other setback distance are allowed,
if recommended by a geotechnical report prepared by a qualified professional (OWTS
Policy Section 7.5.3) \[Must be amended to the Los Angeles County Code of
Ordinances\].
100 feet from springs and flowing surface water bodies where the edge of that water
body is the natural or levied bank for creeks and rivers, or may be less where site
conditions prevent migration of wastewater to the water body (OWTS Policy Section
7.5.4) \[Must be amended to the Los Angeles County Code of Ordinances\].
200 feet from vernal pools, wetlands, lakes, ponds, or other surface water bodies
where the edge of that water body is the high water mark for lakes and reservoirs, and
the mean high tide line for tidally influenced water bodies (OWTS Policy Section 7.5.5)
\[Must be amended to the Los Angeles County Code of Ordinances\].
For new or replacement OWTS where the depth of dispersal system does not exceed
10 feet, the OWTS must be at least 150 feet from a public water well. If the depth of
the effluent dispersal system exceeds 10 feet in depth, the OWTS must be at least
200 feet from a public water well. If the depth of the effluent dispersal system exceeds
20 feet and is within 600 feet of a public water well, the setback must be such that
there is atleast two-year travel time for microbiological contaminants (OWTS Policy
Section 9.4.10).
150 feet from a public water well where the depth of the effluent dispersal system does
not exceed 10 feet (OWTS Policy Section 7.5.6) \[Must be amended to the Los Angeles
County Code of Ordinances\].
400 feet from the high water mark of a reservoir, lake, or flowing water body when the
effluent dispersal system is within 1,200 feet from a public water systems’ surface
water intake point, within the catchment of the drainage, and located such that it may
impact water quality at the intake point such as upstream of the intake point for flowing
water bodies (OWTS Policy Section 7.5.7) \[Must be amended to the Los Angeles
County Code of Ordinances\].
200 feet from the high water mark of a reservoir, lake, or flowing water body when the
effluent dispersal system is located more than 1,200 feet but less than 2,500 feet from
a public water systems’ surface water intake point, within the catchment of the
drainage, and located suchthat it may impact water quality at the intake point such as
upstream of the intake point for flowing water bodies (OWTS Policy Section 7.5.8)
\[Must be amended to the Los Angeles County Code of Ordinances\].
In addition to the State mandated minimum requirements for OWTS treatment
components and dispersal systems horizontal setback and the Plumbing Code horizontal
setback requirements (Table K-1 in Appendix K of the Plumbing Code), the County has
added an additional requirement given its particular locationand needs. Tier 2 OWTS
under this LAMP must be located a minimum distance of:
10 feet from the trunk of any tree (for Oak trees, this requirement extends to 5 feet
outside of the drip line or 15 feet from the trunk, whichever is greater) \[Specified in the
Professional Guide\].
OWTS regulated by the LAMP must meet all of the above horizontal setback
requirements for Tier 2 consideration, summarized in Table 3-4. Table 3-4 summarizes
the horizontal setbacks required under this LAMP, including setbacks that must be
amended to the Los Angeles County Code of Ordinances, discussed above.
Appendix B
Cumulative Nitrate and SaltLoading from
OWTSinLos AngelesCounty
APPENDIX B
WATER QUALITY ASSESSMENT PROGRAM (WQAP)
B-1OVERVIEW OF WQAP
As required by Section 9.3.1 of the OWTS Policy, the County will maintain a Water Quality
Assessment Program (WQAP) to determine the general operation status of OWTS and
to evaluate the impact of OWTS discharges, and assess the extent to which groundwater
and local surface water quality may be adversely impacted. The County shall make
available the WQAP to the RWQCB for its review prior to its implementation. The focus
of the assessment will be areas where different and/or additional requirements are
needed to protect water quality, including consideration of the following items:
Degree of vulnerability to pollution from OWTS due to hydrogeological conditions,
High Quality waters or other environmental conditions requiring enhanced protection
from the effects of OWTS,
Shallow soils requiring a dispersal system installation that is closer to ground surface
than is standard,
OWTS is located in area with high domestic well usage,
Dispersal system is located in an area with fractured bedrock,
Dispersal system is located in an area with poorly drained soils,
Surface water is vulnerable to pollution from OWTS,
Surface water within the watershed is listed as impaired for nitrogen or pathogens,
OWTS is located within an area of high OWTS density,
A parcel’s size and its susceptibility to hydraulic mounding, organic or nitrogen
loading, and whether there is sufficient area for OWTS expansion in case of failure,
Geographic areas that are known to have multiple, existing OWTS predating any
adopted standards of design and construction including cesspools,
Geographic areas that are known to have multiple, existing OWTS located within the
pertinent setbacks identified in the Professional Guide.
As part of the WQAP, the DPH will continue to maintain the inventory for OWTS and
NOWTS in the County, including system location information (Figure 1-1and Figure 1-
2). Figure 2-5shows the number of OWTS and NOWTS in each watershed. The WQAP
will include evaluation of available water quality data for nitrates and pathogens as
reported under existing monitoring programs for domestic wells, public systems/wells
and/or beach water quality or from other sources. The WQAP will also include review of
complaints, variances, failures, and any information resulting from inspections. Data for
other constituents which are needed to adequately characterize the impacts of
OWTS/NOWTS on water quality may also be included in the assessment, where these
data are available.
If elevated nitrogen or pathogen levels are reported under monitoring programs the
results are not necessarily indicative of issues with domestic OWTS, considering that
larger commercial systems and systems managed under the WDR permit process by the
RWQCB tend to have significantly larger design flows and larger contribution to septic
loads throughout the County.
As described in Section 6.4 of the LAMP (reporting to the RWQCBs), every five (5) years
the annual report to the RWQCB will be accompanied by the Water Quality Assessment
Report that summarizes the information and findings from the WQAP.
B-2OWTS GEOGRAPHIC AREAS
The GIS data will allow for the OWTS and water quality data to be organized according
to various geographical areas. The OWTS distribution can be organized by watersheds,
groundwater sub-basins,U.S. Postal Service Zip Code areas, or by delineated impaired
water bodies for use in environmental studies and the preparation of the APMP.
The following sections provide a general discussion for the geographical areas of OWTS
covered by Los AngelesCounty’s LAMP.
Within Los Angeles County’s Jurisdiction
Los Angeles County has contracts with City of Agoura Hills, City of Bradbury, La Canada-
Flintridge, City of La Habra Heights, City of Lynwood, City of Palos Verdes Estates, City
of Rolling Hills, City of Rolling Hills Estates, City of Lancaster, City of Palmdale and the
City of Walnut. The OWTS located within these cities will be included in the Water Quality
Assessment Program (WQAP) and will be included in development of the APMP.
Additionally, any cities that do not now contract with Los Angeles County for LAMP
services, but elect to do so in the future, will be included. OWTS can be geographically
referenced by cities if needed.
Zip Code
The current OWTS inventory provides for ready geographical reference by U.S. Postal
Service Zip Code. Although of some use for evaluating OWTS distributions, distribution
by zip code has limited use for watershed, groundwater basin and impaired water body
analysis.
Watershed
OWTS distribution by watershed will provide information on potential contributions of
OWTS to impaired water. This will aid with development of water quality parameters
loading analyses and potential impacts to impaired water TotalMaximum Daily Load
(TMDL) levels. Other localized focus areas within each watershed may be delineated in
the future if warranted.
TABLE B-1
South County Area (Los Angeles RWQCB Region 4),
Estimated Existing OWTS by Watershed
OWTS NOWTS
Watershed
NumberNumber
Calleguas00
Los Angeles10,951134
San Pedro Channel Islands
30
Watershed
San Gabriel2,54581
Santa Ana1432
Santa Clara (RWQCB Region 4)11,287102
Santa Monica Bay7,238379
TABLE B-2
North County Area (Lahontan RWQCB Region 6),
Estimated Existing OWTS by Watershed
OWTS NOWTS
Watershed
NumberNumber
Antelope-Fremont Valleys16,95541
Middle Kern-Upper Tehachapi-Grapevine10
Mojave1271
Santa Clara (RWQCB Region 6)700
Impaired Surface Water (Figure 4-1)
Impaired water bodies identified below require a 600 feet boundary until a TMDL with
OWTS allotment is adopted. Tier 3 applies to OWTS within the 600 feet boundary until
the TMDL with OWTS allotment is established.
Water Bodies Impaired for Pathogens subject to Tier 3:
Coyote Creek
Malibu Creek (Includes Las Virgenes Creek and Malibu Lagoon)
San Gabriel River Reach 1 (Estuary to Firestone)
San Gabriel River Reach 2 (Firestone to Whittier Narrows Dam)
San Gabriel River Reach 3 (Whittier Narrows to Ramona)
San Jose Creek Reach 1 (San Gabriel Confluence to Temple Street)
San Jose Creek Reach 2 (Temple Street to Interstate -10 at White Ave.)
Sawpit Creek
Walnut Creek Wash (Drains from Puddingstone Reservoir)
Water Bodies Impaired for nitrogen subject to Tier 3:
Malibu Creek (Includes Las Virgenes Creek and Malibu Lagoon)
Malibou Lake
Westlake Lake
Mint Canyon Creek
Santa Clara River Lakes (Lakes Hughes, Muntz, and Elizabeth)
Las Virgenes Creek, Malibu Lagoon, Westlake Lake, Mint Canyon Creek and Santa
Clara River Lakes (Lakes Hughes, Muntz, and Elizabeth) water bodies are included
in the above list because they have been identified as being impaired for nitrogen or
pathogens with OWTS as a potential contributing source. The remaining water bodies
shown above were identified in the State OWTS Policy as impaired for pathogens or
nitrogen with OWTS as a potential contributing source.
TMDLs:
Some of the County impaired water bodies listed due to nitrogen or pathogen
indicators pursuant to section 303(d) of the Clean Water Act have TMDL levels
established by the RWQCB.
Tier 3 applies to OWTS within the 600 feet boundary for the above impairedwater
bodies until the TMDL with OWTS allotment is established.
B-3OWTS IMPACT ANALYSES -METHODOLOGY
Data and Assumptions
The following data will be used to estimate the impact of OWTS on surface and
groundwater quality. Assumptions related to each data set are summarized in the relevant
section.
OWTS Discharge Volumes
Individual OWTS are normally designed on the basis of the estimated maximum daily
sewage flow from the residence or building(s) served. The standard design factor for the
County is 150gallons per day (gpd) per bedroom. The design sewage flow is purposely
set with a margin of safety above the actual wastewater flows,in order to accommodate
maximum usage of an individual system. However, based on information from the US
EPA OWTS Manual (2002) the actual residential sewage generation rates are found to
be in the range of 45 to 70 gpd/per capita. This US EPA estimate is consistent with Los
Angeles Department of Water and Power’s average water usage for a family of four at 77
gallons per person per day (308 gallons per family per day), 62% of which is used for
indoor purposes according to the University of California Los Angeles Institute of the
Environment and Sustainability. Using these two sources, the estimate for actual
residential sewage generation rate for the County is about 48 gpd per person per day (77
gallons per person per day x 62%). Therefore, an average family of four would produce
about 200 gpd of residential sewage. A value of 200 gpd will be used to estimate the
average wastewater flow from residential OWTS in each region.
Background Nitrogen Concentration
Background nitrogen concentration will be assumed based on water quality sampling of
wells in non-agricultural areas where OWTS discharge is not anticipated to affect water
quality. In the absence of this data for the County, a value will be assumed from a review
of data on background nitrogen concentrations in regions with similar climate and
geology.
Soil Denitrification
Total nitrogen removal in the upper soil zones (via denitrification) is typically assumed to
remove 10 to 25 percent of the total nitrogen. For this loading calculation, it was estimated
that 15 percent of the total nitrogen in the percolating OWTS effluent would be removed
by denitrification, based on the average permeability of soil in the region. Seepage pits
shall be excluded from this calculation as their effluents are not subject to soil
denitrification.
Rainfall Recharge (Deep Percolation)
Therechargeareawill be calculated by estimating thetotalacreageofnon-sewered
landwithineachregion considered (watersheds, groundwater sub-basins, U.S. Postal
Service Zip Code areas). Non-seweredacreageincludestheparcelscurrently
developedwithOWTS,vacantdevelopableparcels,aswellasthepubliclandsand
openspaceeasementareas.Landareasservedbypublicsewerswill be excludedfrom
the“rechargearea”.
Deep percolation will be estimated through completion of a water balance analysis, which
will take into account rainfall, runoff and evapotranspiration losses.
Infiltration Rate
Infiltration rates for each region considered will be assumed based on soil type and data
from percolation tests conducted by the county in each region where OWTS are present.
Groundwater Levels
Estimates for the minimum depth to groundwater have been obtained from well
groundwater levels databases and from the underground storage tank case list at the
Department of Water Resources (DWR). Additionally, groundwater levels from wells
found on the Los Angeles County well database were used to estimate local groundwater
levels. The website locations are provided in the list of references at the end of this
section. It should be noted that the depths obtained are considered estimates only and
may vary significantly depending on which aquifer is tapped into.
Nitrate-Nitrogen Loading
Anitrateloadinganalysiswill becompletedusinganannualchemical-waterbalance
analysis.Themethodology to be followedisdescribedinthepublication“Predicting
GroundwaterNitrate-NitrogenImpacts”(HantzscheandFinnemore,Groundwater,Vol.
30,No.4,July-August1992).Accordingtothismethodology,thelong-term
concentrationofnitrateasnitrogen(NO-Nornitrate-nitrogen)intheuppersaturated
3
groundwaterzonecanbecloselyapproximatedbythequalityofpercolatingrecharge
waters.ConsideringonlythecontributionsfromOWTSandnaturalsourcespicked up
byrainfallleachingofsoil andvegetation,theaverageconcentrationofnitrate-nitrogen
in rechargewater,n,isestimatedusingthefollowingequation:
r
where: n=resultantaverageconcentrationofNO-Ninrechargewater,mg-N/l
3
r
W=averageannualvolumeof wastewaterenteringthe soil,acre-ft/yr(AFY)
n= totalnitrogenconcentrationofwastewater, mg-N/l
w
d=fraction ofNO-Nloss dueto denitrificationinthesoil
3
R=averageannualvolumeofrainfallrechargeinsub-basinarea,AFY
n=backgroundNO-Nconcentrationofrainfallrechargeat the watertable,
3
b
exclusiveofwastewater,agricultureorotherdevelopmentinfluences,mg-N/l
Once nitrate loading has been determined for each of the regions covered by the LAMP,
concentrations will be compared to Maximum Contaminant Levels (MCLs, drinking water
standards) to determine areas where further investigation may be warranted. Nitrate
concentrations will also be compared to groundwater nitrate concentration data to
determine regions where nitrate discharges from OWTS may be affecting groundwater
quality. These regions will be subject to additional assessment to evaluate the actual
impact of OWTS discharge on groundwater quality.
Additional Water Quality Assessment Parameters
In regions where the initial water quality assessment determines that OWTS discharges
may adversely affect groundwater and/or surface water quality, additional parameters
may be considered to determine actual impacts of OWTS discharge. Additional
parameters may include:
Bacteria
TDS
Chloride
Sulfate
Boron
Other parameters, such as isotopes and anthropogenic compounds, may be added,
as necessary
B-4POTENTIAL DATA GAPS
Based on the OWTS location, additional data acquisition could be required. This data
could include:
Rainfall Data
Soil Type/Infiltration Rate
Groundwater Level
Groundwater Nitrate data
Additional analytes that could be needed to further constrain the impact of OWTS
include:
Bacteria
TDS
Chloride
Sulfate
Boron
Additional analytes that may be needed to verify OWTS impacts to groundwater are
discussed in the following sections.
B-5VERIFICATION OF OWTS IMPACTS TO GROUNDWATER
Because nitrate, bacteria, TDS, chloride, sulfate and boron have other potential sources
in the environment, additional studies should be considered to verify that the impacts to
groundwater are related to OWTS.
1415
The ratio of nitrogen’s two stable isotopes (N and N) can be used effectively to discern
15
the presence of human wastes (enriched in the N isotope) in plants and algae that
uptake nitrate, contributing to the eutrophication of surface waters.
Somewhat less mobile than the inorganic anions are a variety of organic substances that
can dissolve in groundwater at detectable concentrations. There are two groups of these
organic substances that are most useful. Household products such as cleaning agents
and foods represent the first group. Linear alkyl benzenes (LABS) are components of
common surfactants (e.g., detergents) and ethylene diaminetetraacetic acid (EDTA) is a
chelating agent present in many cleaning products. These two compounds have a
moderate to high water solubility and their biodegradability is limited. Caffeine is highly
water-soluble and has been detected in wastewaters at concentrations approaching 1
mg/L. While caffeine can biodegrade in surface water ecosystems, it is often useful for
groundwater.
A second group of organic substances includes pharmaceuticals such as ibuprofen,
acetaminophen, ethinylestradioland codeine. These drugs are less soluble than
household products, but are quite stable in water and routinely analyzed by commercial
laboratories. Although not pharmaceuticals, a number of sterols produced naturally by the
human body (e.g., coprostanol, cholesterol) are also useful in identifying the presence
and source of fecal contamination—particularly for surface water releases.
Perhaps the least mobile indicators of human wastewater are the various microorganisms
(e.g., viruses, bacteria, protozoa) that are often filtered out or adsorbed by soil particles;
however, they are mobile in groundwater flowing through coarse-grained materials (e.g.,
sands and gravels). Specifically, Escherichia, Streptococci and Clostridia bacteria are
routinely analyzed tomonitor wastewater releases to the environment. Coliphage viruses
are also useful as an indicator of wastewater components (specifically coliform bacteria)
in freshwater and seawater because they are more mobile than their larger bacterial
hosts.
The combination of indicator compounds employed to identify the presence and extent of
releases from OWTS depends on local hydrogeologic conditions, background water
chemistry and characteristics of potential contributors. In addition, the extent to which
specific sources of sewage contamination must be identified will influence both the
number and detection limits of indicator compounds. Generally, common anions are the
quickest and least costly first-tier indicators to employ. If the anion data are inconclusive
or confounded by other contributing sources in the area, organic chemicals related to
household products and/or nitrogen isotope ratios are often the second tier indicators,
depending on whether surface or ground waters are impacted. If the household product
and isotope indicators are inconclusive or unfeasible, the third tier indicators are usually
pharmaceuticals, fecal sterols and/or coliphage viruses.
It should be noted that any combination of indicators could be initially employed for a
specific investigation, depending on the environment impacted and the required certainty
of the source(s). Moreover, bacterial pathogens or their indicators should be tested as
part of any first tier investigation as they are potentially the most hazardous components
of OWTS releases and may be mobile even in environments where hydrologic or
chemical conditions suggest otherwise. In some cases, initial tests for suspected viruses
or protozoa are also warranted.
B-6DEVELOPMENT OF THE ADVANCED PROTECTION MANAGEMENT
PROGRAM
An APMP will be implemented for all OWTS systems that are determined to be Tier 3 and
located within 600 feet of a water body listed as impaired due to nitrogen or pathogen
indicators pursuant to section 303(d) of the Clean Water Act.
The geographic area for each water body’s APMP is defined by the applicable TMDL, if
one has been approved. If there is not an approved TMDL, it shall be 600 linear feet \[in
the horizontal (map) direction\] of a water body where the edge of that impaired water
body is thenatural or levied bank for creeks and rivers, the high water mark for lakes and
reservoirs, and the mean high tide line for tidally influenced water bodies, as appropriate.
OWTS near impaired water bodies that are not listed as impaired due to nitrogen or
pathogen indicators, and do not have a TMDL and are not covered by a Local Agency
Management Program with special provisions, are not addressed by Tier 3.
It is the responsibility of the owner of existing, new or replacement OWTS to confirm
whether the location of his/her system relative to impaired water bodies will classify the
system as Tier 3. The SWRCB provides a map tool on their website
http://www.waterboards.ca.gov/water_issues/programs/owts/index.shtmlthat assists
residents in determining if they are within 2,000 feet of an impaired water body. This
distance is the distance from an impaired water body that the SWRCB considers to be
“near” to a system. If you enter a property address into the map tool, nearby impaired
waters for nitrogen compounds and/or pathogens should be listed. If no nitrogen -or
pathogen-impaired water bodies listed in Attachment 2 of the OWTS Policy and this
LAMP are identified within 2,000 feet of an address, there is a lower potential for the
OWTS to be classified under the Tier 3 requirements or covered under a TMDL
implementation plan based on distance to an impaired water body. If there are nitrogen-
or pathogen-impaired water bodies that are identified within 2,000 feet of an address
using the map tool, there is a higher potential for the OWTS to be classified under the
Tier 3 requirements or covered under a TMDL implementation plan. Due to data
limitations, property owners are strongly advised to conduct further investigation beyond
the SWRCB mapping tool with the help of their local agencies, RWQCB and/or SWRCB
to determine whether their system falls into the Tier 3 category before making any
changes to their system.See the SWRCB website
http://www.waterboards.ca.gov/water_issues/programs/owts/index.shtml.
OWTS that are properly functioning prior to the establishment of TMDLs for an impaired
water body shall not be subject to the APMP if the owner (1) signs a legally binding
document to connect to a centralized wastewater collection and treatment system within
48 months of the nearby water body being classified as impaired due to the influence of
OWTS; and (2) specifies that the date of connection is within 9 years of the nearby water
body being classified as impaired due to the influence of OWTS.
ForOWTS that are subject to the APMP, approved supplemental treatment for nitrogen
and/or pathogens must be used, based on the source of impairment of the nearby water
body.
Any assessment of particular OWTS failure contributing to the water body impairment will
be done by the WaterBoard.