Laguna Street Outfall Rehabilitation Project

Project Activities

The Laguna Street outfall rehabilitation will include the following activities: concrete spalling and crack repair, rehabilitation of the existing discharge pipe with carbon fiber wrap or similar material, repair to the baffles, and repair of riprap around the discharge pipe. The work will not impact the discharge capability or any sewer operations.

What is a Combined Sewer Discharge?

San Francisco is the only coastal city in California with a combined sewer system that collects and treats both sewage and stormwater in the same network of pipes and treatment facilities. This combined system means that San Francisco treats stormwater runoff when other coastal cities in California would have stormwater – and the debris and pollutants it picks up – flow untreated into water bodies.

In San Francisco, the debris and pollutants in stormwater runoff are treated to the same high standards that the SFPUC uses to treat sewage from buildings before being discharged into San Francisco Bay or the Pacific Ocean. However, during intense storms the system can reach capacity. When this occurs, it is necessary to discharge partially treated wastewater through outfalls around the City. This combined stormwater and wastewater discharge is more than 90% stormwater. It also receives partial treatment – the equivalent of primary treatment at one of our wastewater treatment plants – before it is discharged. This is known as a combined sewer discharge.

These discharge events are monitored and reported in a timely manner to maintain compliance with all regulatory and permitting agencies. Under the Sewer System Improvement Program, projects such as Baker Beach Green Streets are being constructed to further reduce storm-related discharges. Visit the Beach Water Quality Monitoring Program for more information on storm-related discharges and water quality at beaches.

About the SFPUC and Our Combined Sewer System

We are the San Francisco Public Utilities Commission, a not-for-profit public utility providing San Francisco with water, power, and sewer services. Every day we collect and treat both sewage and stormwater from homes and businesses to protect public health and the environment. This project is part of the San Francisco Public Utilities Commission's Wastewater Capital Improvement Program to upgrade and modernize San Francisco's combined sewer system for current and future generations.