The Westborough Water District (District) owns the water and sanitary sewer system which serves the Westborough area of South San Francisco. We are located in northern San Mateo County, about 9 miles south of San Francisco. The District serves primarily residential community with three small shopping centers. The District’s boundary encompasses about 1 square mile of land. The District provides water and sewer service to a population of 12,481 through 3,882 service connections. The population was calculated using the Department of Water Resources population tool.
The District was formed in 1961 under the County Water District Act of California. The District contracts with the San Francisco Water Department to purchase water wholesale from the San Francisco Public Utility Commission. With regard to the sanitary sewer system, the District contracts with the City of Daly City (North San Mateo County Sanitation District or NSMCSD) for general maintenance, emergency response, collection and treatment. The District does not physically perform any of the maintenance, repairs or treatment of the sanitary sewer system as those responsibilities are conducted by agreement through the NSMCSD.
The District has three sewer lift stations which pump sewage from the District to the NSMCSD’s treatment plant. The Avalon Sewer Lift Station has two pumps and both the Westborough and Rowntree Lift Stations have three pumps at each station. The District’s sanitary sewer flow averages approximately 884,722 gallons per day during wet weather compared to 782,716 gallons during dry weather. This District has about 18.8 miles of gravity sanitary sewer mains and a three-quarter mile of sewer force main. Since 2010 the District has had only one sanitary sewer overflow that was attributed to an electrical power failure.