Wastewater Regulations Are Effective
The NPDES program is one of the most successful environmental programs ever implemented. Enactment of the federal Clean Water Act in 1972 established the NPDES program. Since then, publicly owned treatment works (POTWs) have installed primary, secondary, and in some instances tertiary treatment, and San Francisco Bay water quality has improved considerably.

As shown to the right, since implementing the NPDES wastewater program, suspended solids (TSS) and organic matter (BOD) discharges from publicly owned treatment works have dropped 80% to 90% despite wastewater flows more than doubling!

Likewise, coliform bacteria concentrations in San Francisco Bay have dropped more than 90% due to NPDES wastewater program implementation. More information regarding water quality in San Francisco Bay is available. The San Francisco Estuary Institute provides additional information.

Data and figures from:
Fred Krieger, Michele Plá, and Charles Weir. The History of Municipal Wastewater Treatment: 35 Years of POTWs Protecting the Bay.

As published in:
San Francisco Estuary Institute (SFEI) 2007. The Pulse of the Estuary: Monitoring and Managing Water Quality in the San Francisco Estuary. SFEI Contribution 532. San Francisco Estuary Institute, Oakland, CA.
Bacteria in Offshore Waters
Click for Larger View

Total BOD and TSS Loading to the Bay
Click for Larger View