(Formerly “Seismic Upgrade of Bay Division Pipelines at the Hayward Fault”)

Two major water transmission pipelines, BDPL Nos. 3 and 4, pass through the Weibel Neighborhood of Fremont, California, carrying drinking water to the majority of the Bay Area’s 2.4 million customers. These pipelines are 6.5 feet and 8 feet in diameter, respectively, and cross three major traces of the Hayward Earthquake Fault. Should an earthquake on that fault occur, it could rupture one or both of these pipelines.

Construction on the Crossover/Isolation Valves at the Hayward Fault Project began in Fall 2006, and is ongoing simultaneously at two sites.  Both sites are within the SFPUC 80-foot right-of-way, one to the north and one to the south of the Hayward Fault crossing. The northern location is at Tissiack and Paseo Padre Parkway, and the southern site is at Crawford and Bradley Streets.

Each site contains the following:

Shut-off Valves and Crossover Piping
The valves and piping will be enclosed in vaults that are predominantly underground. The aboveground portion will be approximately 3 feet high, 50 feet wide and 75 feet long.  The valves will allow SFPUC to close off portions of the pipeline should a rupture occur on or near the Hayward Fault crossing.  The crossover piping will allow the flow of water to be transferred from one pipe to another.  These facilities will function in an emergency or for planned maintenance. 

Electrical Equipment
Electrical equipment will be housed in a separate underground vaults within the same lot, also 3 feet high, approximately 20 feet wide and 48 feet long.

Satellite Dish
In order to monitor and control the valves remotely, the project will install a 4-foot diameter satellite (V-SAT) dish at each site. The V-SAT dish will enable the SFPUC to remotely monitor and operate the valves.

Anticipated completion date for construction is late 2007 / early 2008.  A second project (Phase B) will assess and seismically retrofit the pipelines that cross the Hayward Fault between the two vaults.  Phase B construction is scheduled to begin in 2010.  

Need more information?
Contact Christina Kerby at (415) 554-3203 or via email at ckerby@sfwater.org