Peninsula Pipelines Seismic Upgrade

In 2002, the San Francisco Public Utilities Commission (SFPUC) launched a $4.8 billion water system improvement program designed to provide reliable, affordable, high-quality water in compliance with environmental and water quality regulations. It also needed to transmit this water in a system with improved seismic and delivery reliability, while achieving water supply level of service goals.

As part of the improvement program, SFPUC initiated the PPSU to strengthen the seismic reliability of its pipelines, including the 60-in. Sunset Supply Branch Pipeline, the 66-in. San Andreas Pipeline No. 03, and the 54-in. San Andreas Pipeline No. 02. These three transmission lines connect SFPUC’s 180-million-gal-per-day Harry Tracy Water Treatment Plant to communities on the northern San Francisco Peninsula. Thus, a seismic threat in this area becomes a threat to the availability of clean water.

This project was located at five separate sites located in Millbrae, San Bruno and South San Francisco. Work included approximately 920 LF 61” San Andreas Pipeline (SSBPL) Pipe at the Millbrae Site, 1,150 LF 54” SAPL2 Pipe at the San Bruno South Site, 1,000 LF 66” SAPL3 Pipe at the San Bruno South Site, 700 LF 54” SAPL2 Pipe at the South San Francisco Site, 700 LF 54” SAPL2 Pipe at the Colma Site. In addition concrete encasement of the SSBPL was required and described as: 150 LF of the 61” SSBPL Pipe at the Millbrae Site, 130 LF of the 54” SAPL2 Pipe at the San Bruno South Site, 130 LF of the 66” SAPL3 Pipe at the San Bruno South Site. All five major sites included demolition, Corrosion Protection, Turnout Vaults, mechanical and turnout piping, Roadway Restoration and Improvements.