Storm Water Program

SVCW helps prevent pollution of our waterways by proactively managing storm water and urban runoff.

Storm water runoff is any water that falls and is transported over land or pavement into local bodies of water through the storm drain system. Storm water is rain and water from sprinklers or irrigation of yards and gardens.

Urban runoff is storm water that picks up pollutants on its way into a storm drain or waterway. It often includes automobile pollutants, pesticides, fertilizers, trash, soap, and other materials and chemicals. Once urban runoff enters the storm drain, it goes directly into the nearest body of water like creeks, San Francisco Bay, or the Pacific Ocean, without treatment.

SVCW works with the San Mateo Countywide Water Pollution Prevention Program to conduct storm water inspections of commercial and industrial businesses in Belmont and San Carlos. These cities have authorized staff to conduct inspections to prevent storm water pollution. To make efficient use of staff time, SVCW inspectors combine storm water inspections with FOG inspections to reduce the number of visits.

The land that water flows over or through on its way to a creek, delta, bay, or ocean is called a watershed. Everyone lives in a watershed, and everything that happens in the watershed affects water quality and the heath of animals, plants, and the people who live nearby. Pollution in distant parts of a watershed can be washed into storm drains, and cause problems downstream. Human activities can either harm or improve the condition of a watershed, including its water quality. There are 34 watersheds in San Mateo County. Most of the storm water in San Mateo County drains into San Francisco Bay.

There is an important difference between storm drains and sewers: water from the sanitary sewers, including water from your bathtub and toilet, is treated. Toxins are removed before the water is released into our waterways.

Storm water is not treated. Storm water and all the pollutants that flow into outdoor drains at businesses, homes, parking lots, from streets into the gutter and into storm drains discharge directly into our creeks and other bodies of water.

For more information about the San Mateo Countywide Water Pollution Prevention Program go to

San Mateo Countywide Water Pollution Prevention Program Best Management Practices (BMPs)

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