Controlling Storm Water Pollution

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

Every day, pollution like trash, oil, pesticides, fertilizers and household chemicals are washed into the Bay by rainwater and water from our sprinklers, spouts and hoses. Paved concrete and asphalt surfaces on roads, buildings and parking lots send rainwater rushing into gutters and storm drains. This polluted storm water – carrying all the pollution it collects along the way – then gets emptied into creeks and sloughs that empty into the Bay.

Storm water pollution is the largest source of pollution to San Francisco Bay. Each pollutant can have impacts on the plants, animals and people that depend on the Bay:

• Pesticides, fertilizers, and other chemicals poison the aquatic food web;
• Bacteria and other pathogens make waterways unsafe for recreational activities like boating and swimming;
• Dirt from construction zones and eroded creeks cloud the water, destroying habitat and impeding healthy plant growth;
• Trash such as plastic bags and bottles, and cigarette butts suffocate and disable wildlife.  

Reducing Storm Water Pollution Through Low Impact Development

San Francisco Baykeeper has worked for twenty years to reduce storm water pollution to the Bay by challenging weak regulations of storm water at the municipal and regional level. Unfortunately, regulations have proven to be largely ineffective in actually reducing storm water pollution to the Bay. For example, Bay fish are still unsafe to eat because of high PCBs and mercury concentrations, and many Bay Area creeks cannot support healthy fish populations because of pesticide contamination.

Baykeeper is part of a growing movement to address storm water pollution through low impact development. Low impact development ("LID") 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. Click here to find out more about Low Impact Development.