Every year during rainy winter weather, millions of gallons of raw and undertreated sewage are spilled into San Francisco Bay and local waterways. Baykeeper has been working to stop sewage spills to the Bay for more than a decade, and in 2008, we launched our Sick of Sewage campaign. Since then, we’ve made significant progress toward keeping sewage out of Bay Area homes, streets, creeks, sloughs and the Bay. In fact, thanks to Baykeeper’s Sick of Sewage campaign, within the next ten years sewage should cease to be a major threat to the Bay.
Sewage Spills: A Major Threat to the Health of the Bay
Sewage contains bacteria, viruses and other pathogens. When windsurfers, swimmers, boaters, fishermen and others come in contact with water contaminated with raw or undertreated sewage, it can cause persistent skin and sinus infections and painful stomach disorders. Sewage can also deplete oxygen in the Bay, threatening fish, seals, other sea creatures and plant life.
The primary cause of sewage spills is the dilapidated state of the Bay Area’s municipal sewer collection systems and treatment plants. Before Baykeeper began our Sick of Sewage campaign, most of these collection systems and treatment plants had not been upgraded since they were built in the 1950s and 60s. During the rainy season, large amounts of rainwater seep into the sewer systems through crumbling pipes or through connections between the sewer and separate storm drain systems. This increased volume fills sewer pipes, which can rupture or back up, causing spills into streets and storm drains that carry the pollution to the Bay. Rainwater seeping into sewer pipes also swells the volume of water flowing into treatment plants, which can overwhelm treatment plant capacity. As a result, hundreds of millions of gallons of treated and untreated sewage get discharged directly into the Bay or into local waterways that empty into the Bay.
Learn more about what causes sewage spills: click here to watch KQED Quest’s Wastewater Woes news video.
Baykeeper Wins Sewage Pollution Cleanup
Using the federal Clean Water Act, San Francisco Baykeeper has won upgrades to many sewer systems in the Bay Area. We have successfully secured legally-binding agreements to upgrade sewage infrastructure in 20 cities across the Bay Area, leading to significant progress in cleanup of sewage contamination of the Bay. Read more about our legal actions to clean up sewage spills in the Bay.
We are monitoring sewer agencies to make sure they follow through on their commitments and that the upgrades they put in place lead to cleaner, safer Bay waters. Many of the sewer system upgrades Baykeeper has won are still in progress, but some are already operational. In some areas, sewage spills are down by 50-75%. One city, South San Francisco, finished all its repairs and upgrades three years ahead of schedule and is no longer causing sewage spill problems for the Bay. Read about recent progress to reduce sewage spills as a result of Baykeeper's legal actions.
Tracking Sewage Spills
Every winter Baykeeper compiles and analyzes reports of sewage spills from around the Bay Area to establish the total impact of dilapidated sewer systems on the health of the Bay. See a map of sewage spills in rainy season 2015-16. See a map of sewage spills in rainy season 2014-15. See a map of sewage spills in rainy season 2013-2014. See a map of sewage spills in rainy season 2012-2013.
In winter 2010-11, a year of exceptionally heavy rains, nearly a quarter billion gallons of sewage and contaminated rainwater were released into the Bay and local waterways. See a map of 2010-2011 sewage spills.
How You Can Help Stop Sewage Spills
Baykeeper works in Bay Area communities to increase the public’s understanding of how our daily actions impact our sewer systems and; can lead to sewage spills. There are easy changes you can make at home to protect San Francisco Bay and our community from sewage pollution. Read Baykeeper’s tips to help prevent sewage spills and overflows to the Bay.