Sunset Reservoir North Basin Seismic Retrofit

This project was the second part of a two-part project that addressed the seismic readiness condition of the Sunset Reservoir. The Sunset Reservoir provides 60 percent of the clean water supply for the City of San Francisco, and it is critical in case of major fire or earthquake.

The seismic upgrade project work included strengthening the reservoir by the construction of six new moment frames, 11 stainless steel brace frame assemblies, 29 CIDH piers (ranging from 40 to 80 feet deep) connecting to 29 grade beams around the reservoir, and 29 shearwalls and struts inside the reservoir. The contract scope also included pouring a 7-in. slab on more than 300,000 square feet of the reservoir floor.

Since construction activities occurred in a containment of potable water, none of the equipment was powered by diesel or gas. Shimmick only relied on propane to power all the equipment that was inside the reservoir.