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Southeast Treatment Plant

Rendering of new Biosolids siting

Southeast Treatment Plant Campus Vision

The Planning Department is conducting the environmental review for the proposed Biosolids Digesters Facilities Project. Learn More.

 Image of Factsheet for Treatment Plants

 Treatment Plants Factsheet

Located in Bayview Hunters Point, the Southeast Treatment Plant (SEP) is nestled in the midst of a mixed industrial, commercial and residential area; with some neighbors only a street’s width away from the treatment plant.

The SEP is San Francisco’s largest and oldest wastewater facility, responsible for treating nearly 80% of the City's flow. Wastewater is transported to the SEP through a grid of transport/storage facilities, sewers, and five major pump stations. The SEP treats 57 million gallons per day (MGD) of wastewater and handles 160 wet tons of biosolids each day. During a rainstorm, it has the capacity to treat up to 250MGD of wastewater.

The Need for Improvement

Built in 1952, many parts of the SEP facilities represent 1940’s technology Aerial Photo of SEP and are operating well beyond their useful lives. Through the Sewer System Improvement Program (SSIP), the SEP will undergo operational improvements and seismic upgrades in order to ensure the reliability of the sewer system and to protect the health of our community and environment.

These proposed SSIP improvements incorporated public input from the Southeast Digesters Task Force, an advisory group of neighborhood and business interests who provided recommendations on reducing community impacts. Check out our page dedicated to the upgrades going on at the Biosolids Digester Facilities.

Snapshot of the Southeast Treatment Plant

 SEP View from the Street

  • Built in 1952 and serves the bayside
  • Largest dry weather facility in SF, treating 80% of the City’s flows
  • Treats 57 million gallons per day (MGD) of wastewater per day and up to 250 MGD during rain storms
  • Located on Phelps Street near Third and Evans streets in the Bayview District







  • Structural and seismic retrofits
  • Upgrades to oxygen and influent pumps
  • Odor control improvements
  • Architectural and landscape improvements to the perimeter
  • Check out this informative article about improvements at the Southeast Plant in the Potrero View!
ssip project benefits
  • Improved process performance
  • Odor control
  • Seismic improvements
  • Improved operating reliability and efficiency
  • Minimized neighborhood impacts
  • Improved visual aspects of the plant
  • Upgrades to the existing digesters
  • New biosolids facility

Last updated: 5/4/2017 11:30:12 AM