October 2025
San Francisco’s oldest wastewater treatment plant modernized with new $717 million headworks facility
San Francisco, CA - Walsh Construction, as part of a joint venture with Sundt Construction, is proud to announce the completion of the new Headworks Facility at the San Francisco Public Utilities Commission’s (SFPUC) Southeast Treatment Plant. This $717 million project marks the first major milestone in SFPUC’s multi-billion-dollar program to transform its 1950s-era facility into a modern, resilient resource recovery center.
Modernization for the Future
The new Headworks Facility is the primary intake and pre-treatment area for nearly 80% of San Francisco’s wastewater, an average of 45 million gallons daily and up to 250 million gallons during wet weather events. Its design and construction provide essential upgrades to protect the city and its waterways:
• Built to withstand a magnitude 7.8 earthquake on the San Andreas Fault.
• Engineered to accommodate 36 inches of sea level rise, ensuring long-term resilience.
• Removes grit with 95% efficiency, a 45% improvement over the former system, protecting downstream treatment systems.
• Advanced odor control technology significantly improves air quality for the Bayview neighborhood.
• Consolidated operations from two outdated headworks facilities into one modernized, more reliable system.
• Enhanced wet weather pumping capacity, ensuring the Bruce Flynn Wet Weather Pump Station can operate year-round.
Community Impact and Recognition
The Headworks Facility represents more than just an infrastructure upgrade, it brings meaningful community and economic benefits. Local residents contributed more than 414,000 craft hours, and small businesses across San Francisco earned more than $100 million in project contracts. In addition, the facility now features Whorl Whirl: Our Circular Nature, a permanent 335-foot-long public artwork by artist Norie Sato that celebrates water’s connection to nature and the Bayview community.
Industry recognition has further highlighted the project’s significance, with the facility receiving the Water Environment Federation’s 2025 Project Excellence Award and the Envision Gold Award from the Institute for Sustainable Infrastructure.
The Headworks Facility was designed by Carollo Engineers and delivered by the Sundt/Walsh Joint Venture.
Read more about the project here: https://www.sfpuc.gov/about-us/news/sfpuc-modernizes-san-franciscos-oldest-wastewater-plant-new-717-million-headworks