Controlling Urban Storm Water Pollution

A Low-Profile But High-Impact Source of Pollution to the Bay

Storm water is the largest source of pollution to San Francisco Bay. When it rains, pollution like trash, oil, pesticides, fertilizers, household chemicals, and legacy toxic pollutants are washed into the Bay without being treated or filtered. Paved concrete and asphalt surfaces on roofs, driveways, streets, buildings, and parking lots send rainwater rushing into gutters and storm drains. This storm water – carrying all the pollution it collects along the way – then gets emptied into creeks and sloughs that flow into the Bay, or into the Bay itself.

Each pollutant can have impacts on the plants, animals, and people that depend on the Bay:

  • Many Bay Area creeks cannot support healthy fish populations because of pesticide contamination.
  • Fertilizers contribute to growth of algae and reduced oxygen in the Bay.
  • Bay fish are unsafe to eat because of high PCBs and mercury concentrations.
  • Copper causes salmon to lose their ability to find their spawning streams.
  • Nickel is lethal to shorebirds.
  • Oil and grease are toxic to the hearts of fish.
  • Bacteria and other pathogens make waterways unsafe for recreational activities like boating and swimming.
  • Dirt from construction zones and eroded creeks clouds the water, destroying habitat and impeding healthy plant growth.
  • Trash such as plastic bags and bottles clogs waterways and can suffocate and disable wildlife. Cigarette butt filters release toxic chemicals and become lodged in the digestive tracts of seals, birds, and many sea creatures.

Baykeeper works to reduce storm water pollution in San Francisco Bay in several ways:

Assuring Cities Meet New Standards to Clean Up Storm Water

Baykeeper helped secure region-wide regulations, adopted in 2009, that require Bay Area city governments to control storm water pollution. For example, city governments are required to reduce their pesticide use in such locations as parks, city-owned land, roadway median strips, and city buildings. Cities are also required to ensure that new development and redevelopment projects include low-impact development features. Low impact development aims to stop storm water pollution before it occurs by designing buildings, roads, and public areas in a way that mimics nature’s way of processing rainwater – letting it percolate, filter, and gradually flow into groundwater, creeks, streams, and the Bay. Baykeeper is watchdogging cities’ progress at meeting these new regulations and providing guidance on needed improvements. Read more about progress cities are making to control storm water pollution of the Bay.

Curbing Industrial Storm Water Pollution

More than 1,300 industrial facilities discharge polluted rainy-season runoff into storm drains that lead to San Francisco Bay, or sometimes directly into creeks or the Bay itself. Baykeeper is working to rein in this widespread, illegal storm water pollution of the Bay with our Bay Safe Industry Campaign.

How You Can Help Reduce Urban Storm Water Pollution

In your home, garden and everyday life, there are lots of ways to help reduce storm water pollution. Find out more about what you can do.