The Southeast Treatment Plant (SEP) in San Francisco, originally built in 1952, is undergoing a headworks upgrade to modernize its aging infrastructure. This effort, part of a broader $3-billion investment in the city’s wastewater system, aims to improve performance, enhance seismic resilience, and provide operational flexibility for decades to come. A recent article on ENR California, titled “San Francisco Wastewater Project Conquers a Tight Footprint by Thinking Vertical,” delves into the details of this transformative project.
Reimagining Wastewater Treatment in a Tight Urban Footprint
According to the article, replacing the existing headworks facilities is no small feat. As Jignesh Desai from SFPUC colorfully describes, the project is “like performing a head transplant while keeping the patient alive.” The $718-million project consolidates two existing headworks into a single, advanced 250-million-gallon-per-day all-weather facility that represents a significant leap forward in urban wastewater management.
The new facility delivers remarkable improvements that set new standards for urban wastewater infrastructure. Engineered to withstand up to a 7.8 magnitude earthquake and prepared for 36 inches of anticipated sea-level rise by 2100, the facility represents a forward-thinking approach to resilient municipal infrastructure. It supports San Francisco’s combined sewer system, treating an astounding 40 billion gallons annually while managing peak grit loads nearly twice the industry standard.
The article also highlights how the project site presented extraordinary challenges that demanded creative engineering solutions. With a minimal 31,500 sq ft footprint nestled among industrial, commercial, and residential areas, and bordered by transportation corridors, the team faced the intricate task of maintaining continuous wastewater treatment operations while completely reimagining the facility’s infrastructure.
Overcoming Urban Engineering Constraints Through Vertical Innovation
Carollo emerged as a critical partner in this transformative project. Brought on in 2016, our team provided essential support to SFPUC through crucial planning phases. We developed a comprehensive conceptual engineering report that became the foundational blueprint for this innovative project, demonstrating our expertise in navigating complex infrastructure challenges.
Our team’s approach centered on vertical innovation and strategic problem-solving. Jim Hagstrom, a Sr. Project Manager at Carollo, spearheaded unique solutions that maximized the limited space. The project reduced screen channels from eight to four through advanced hydraulic design, implemented high-efficiency grit removal technologies, and utilized vertical construction and stacking of critical processes to overcome spatial limitations.
Sustainability and Community Benefits for Modern Wastewater Systems
The new headworks facility not only improves operational efficiency but also enhances the plant’s relationship with its neighbors. In addition to reducing odors, the project earned an Envision Gold award from the Institute for Sustainable Infrastructure for its environmental and community-focused design.
The SEP headworks project showcases how creative engineering can transform complex challenges into successful, sustainable solutions. Read the full article to learn more about Carollo’s role and the innovative strategies that made this project a success.