San Francisco Bay Region
Internet Address: http://www.swrcb.ca.gov
1515 Clay Street, Suite 1400, Oakland, California 94612
Phone (510) 622-2300 Fax (510) 622-2460
August 26, 1999
Mr. Patrick Sweetland
City of Daly City
Dept. of Water and Wastewater Resources
153 Lake Merced Blvd.
Daly City, CA 94015
SUBJECT: COMMENTS ON WESTSIDE BASIN PROPOSED GROUNDWATER MANAGEMENT PLAN
Dear Mr. Sweetland:
This letter provides our comments on the Westside Basin Proposed Groundwater Management Plan. Overall the Management Plan is an excellent step toward better coordination, monitoring and understanding of the basin. The parties are commended for working together on this valuable project.
Based on our review of the report, we have the following comments:
1. Although there is limited data, several Daly City wells are showing gradual increases in chloride concentrations (see pages 3-5, 3-8 and Figure 3.4a). Implementation of measures to prevent saltwater intrusion is strongly urged.Thank you for providing the Regional Board with an opportunity to review the Management Plan. Please contact Linda Spencer of my staff at (510) 622-2420, e-mail [email protected], or Greg Bartow at (510) 622-2315, e-mail [email protected], if you have any questions.2. The integrity of Lake Merced must be preserved. However, despite years of study, the understanding of the connection between the lake level and the water table is still uncertain. Therefore, we urge the implementation of the Tier 1 tasks, especially those related to maintaining Lake Merced.
3. Existing beneficial uses listed in our Water Quality Control Plan (Basin Plan) for Lake Merced include Cold Freshwater Habitat, Warm Freshwater Habitat, Water Contact Recreation and Noncontact Water Recreation. There is also the potential Municipal and Domestic Supply beneficial use. A 1993 San Francisco Water Department Planning Study concluded that a lake level of 26 feet was needed to maintain the beneficial uses of the lake. Recent water level data indicates the lake levels are between 19 and 20 feet, significantly below this level. Threfore, it appears that the existing beneficial uses are impaired.
4. The proposed groundwater monitoring program outlined on pages 12-19 is an important element of the Management Plan. It would benefit the monitoring program if organic compounds could be included in the list of analytes (e.g., USEPA Methods 8260, 8080 and 8270).
5. We continue to be interested in protection of groundwater in the Westside Basin, and want to participate in the process. Please continue to keep us informed of future issues and progress.
6. In an upcoming Draft Basin Plan Amendment, the Westside Basin will be identified as a Significant Drinking Water Resource. For such groundwater basins, we will recommend that "Cleanup strategies should be focused on actively maintaining or restoring groundwater quality to drinking water standards. Cleanup, spill prevention and education efforts within the source water protection zones of existing municipal wells should be the top priority of local and state programs. Also areas with a high density of potential conduit wells and/or shallow backyard wells may need to receive higher priority and be subject to more detailed investigations than other areas." We will send copies of the Draft Basin Plan Amendment to you and th eother Westside Basin Partners when it becomes available.
7. Please correct the mailing list shown in Appendix A as follows: Ron Gervason, California Regional Water Quality Control Board, San Francisco Bay Region, 1515 Clay Street, Suite 1400, Oakland, CA 94612.
Sincerely,
(signed)
Ron Gervason, Chief
Policy and Planning Division
cc: Attached Mailing List
Westside Basin Mailing List
John Plummer
Friends of Lake Merced
100 Santa Barbara Avenue
Daly City, CA 94014
Michael Carlin
San Francisco Public Utilities Commission
1155 Market Street, 4th Floor
San Francisco, CA 94103
John Fio
HydroFocus, Inc.
P.O. Box 477
Dixon, CA 95620
Gene Grabelle
California Water Service Company
80 Chestnut Avenue
South San Francisco, CA 94080
City of San Bruno
Department of Public Works, Water Division
567 El Camino Real
San Bruno, CA 94066
