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HomeMy WebLinkAbout1995-05-09 - AGENDA REPORTS - FOUR OAKS AREA GROUND WATER (2)AGENDA REPORT City Manager Item to be pre; 431ony J. Nisich, UNFINISHED BUSINESS DATE: May 9, 1995 SUBJECT: FOUR OAKS AREA HIGH GROUND WATER DEPARTMENT: Community Development :4Ws.s• M This year's prolonged and intense rainy season has again resulted in a significant rise in the water table in the area of Four Oaks. Historical data indicates that high rainfall amounts over the course of a winter causes the water table to rise significantly due to the "recharge" of ground water supplies. The result of high ground water can result in springs, artesian wells, and in the case of the area shown on the attached vicinity map, a water table elevation which is higher than the ground surface, During the winter of `92293 the issue of high ground water was first brought to the attention of the City. In response, City staff initiated frequent sweeping of the affected area to control algae. In addition load limits were placed on the streets to restrict heavy vehicles from damaging the roadways. In an effort to resolve the reoccurring issue, staff worked with FEMA to fund improvements which would eliminate the problem. The application was approved in April 1994. The approval included a remedy for both the Lakemore and Four Oaks areas. The Lakemore area improvements consist of construction of a drain line and street paving. The Lakemore drain line and street paving are currently being advertised for bid. The project is currently scheduled to be awarded at the May 23 Council meeting. The Four Oaks area improvements are far more complicated and have policy implications both short and long term. The remedy proposed involves long-term, periodic pumping to lower the groundwater levels in the four block area during times when groundwater levels are high (historically three-four months every ten years, but more often recently). Staff has prudently investigated problems of similar situations which have plagued other cities rather than proceeding with the hastily prepared and approved FEMA project. In Simi Valley and the San Bernardino area, similar projects have resulted in litigation against the cities. In one case the groundwater was allegedly lowered too much, causing settlement.. In another, the levels were allegedly not lowered enough to meet expectations. After consultation with the City Attorney and others,including the geologic consultant a test of an existing well, located west of the subdivision was completed approximately two weeks ago. It included drilling two monitoring wells --one in Cedarcreek Street near Glasser, and one along the flood control channel south of Delight Street. The test pumping significantly reduced the ground water level. _; Agenda Item: 1, 1i Ulu FOUR OAKS HIGH GROUNDWATER May 9, 1995 - Page 2 Staff has met with the area residents on August 31, 1994 and February 15, 1995 to discuss the process for testing and cost of permanent installation and maintenance. At each of the meetings, the matter of establishing a method of collecting maintenance costs was discussed. At those meetings, there was some support for establishing an assessment district for this purpose. Staff once again met with area residents on May 3, 1995 to discuss the testing results, formation of a district and the estimated annual assessment. There were approximately 90 people in attendance, and the majority showed support for the formation of a district to address ongoing operations of the well. With that understanding, staff recommends a petition be circulated to form an assessment district. In addition, the residents were concerned with the current situation, and they requested the City take immediate action to lower the groundwater. If through the circulation of a petition there is not sufficient support, staff will have to reevaluate and recommend alternatives. The two alternatives which do exist are formation of a district that the City would partially fund or to drop the project. In summary, the test -pumping which was performed reduced the ground water level but did not totally eliminate the problem. Steps have been taken to limit the size of trash trucks to reduce pavement damage. Also street maintenance has been increased in this area to protect the City from additional liability. It is staffs opinion that the consultant's recommendation to drill two wells, which was approved by FEMA, will perform satisfactorily to lower the ground water level. Action has been slow on the Four Oaks portion of the project, due primarily to taking cautionary steps to avoid beginning a project which could cause more problems than it solves; thus creating additional liability for the City and attempting to find acceptable methods of paying for maintenance which is the portion of the project not funded by FEMA. In the interim, we are continuing to monitor the area. It has been shown by the test pumping that it is possible to lower the high water problem, and therefore the community has asked that Council authorize $100,000 in General Fund Contingency to restart pumping of the existing well. It is estimated the daily cost to pump the well would be between $700 and $1,000 per day. The City is currently spending approximately $1,500 a week plus additional costs for trash pickup and temporary measures which include daily inspection, sidewalk sweeping and increased street sweeping. The estimated cost to the City for additional refuse pick-up costs is $2,500 per month. MPLISHMENT During the two-year period since the April 1993 occurrence, the following has been done: 1. Completed application and received approval for FEMA grant. 2. Retained a groundwater hydrologist to provide alternative remedies, 3. Met with residents three times to discuss alternatives. FOUR OAKS HIGH GROUNDWATER May 9, 1995 - Page 3 4. Retained a consultant to study the establishment of a maintenance assessment district. 5. Studied potential problems which could result in the Four Oaks area. 6. Completed test -pumping of the existing well and noted significant improvement in drawdown of water flowing in the streets.. 7. Complete Lakemore Area improvement plans which are out to bid and scheduled to be awarded May 23. RECOMMENDATION Staff recommends that the City Council: 1. Receive presentation and file report. 2. Schedule field tour of affected area if desired. 3. Direct staff to circulate a petition for establishment of an assessment district. to finance ongoing operation of the permanent well system approved by FEMA. 4. Transfer $10,000 from General Fund Contingency Account No. 01-4101-290 to Account No, 01-96084-227 for additional refuse pick-up costs. ATTACHMENT Vicinity Map RGN:hds c...dmf.w.A.xgn EXHIBIT "A" CITY OF SANTA CLARITA FOUROAKS AREA GROUND WATER �u9�A Gauntry I i t.l g SANTA CLARITA I t S Newhall LEGEND: r = PROJECT SITE LOCATION �• CLI'I OF S A C A VICINITY MAP NT.S. R NEWS t �. �� ✓F wul SM W � i 4 `' v'o � d � r• ^ i J4i Kms: St Y 7� � �t CANYON LEGEND: �\ ✓1//J s PROJECT SITE LOCATION LOCATION MAP NT.S.