The new bridge at 24103 Congress Springs Road in Saratoga, CA provides the only access to the Ellison Conservation Center for Wildlife Care. The bridge crosses a creek as well as a right lateral slip fault that can produce relative displacements of up to 20 feet along the fault. The bridge is designed to accommodate those displacements and remain in service.

The 85-foot main span over Saratoga Creek is a 2.5-foot deep prestressed void-formed slab The pile-supported seat type abutment on its north end incorporates a 20-foot long runout grade beam to allow for the 20-foot lateral displacement associated with the design earthquake. The shallow pier on the south end is over the slip fault shear zone and lis built over a 10-foot deep prism of ductile engineered fill that decouples it from the shearing soils. The the prism was lined with an 80-mil HDPE membrane and 3 inches of rigid Styrofoam. It is filled with Class II fill placed in 9-inch layers with triaxial geogrid. The prism iss topped with 2.5 feet of three quarter inch crushed stones.

The north approach slab is a conventional reinforced concrete slab-on-grade integral with the abutment backwall. It is 20-feet wider than the bridge deck to accommodate the displacements associated with the design earthquake.

The south approach is a reinforced concrete slab-on-grade continuous with the main span superstructure. It varies in thickness from 30 inches at Pier 1 inch to 8 inches at its southern end. This slab is designed to support the main span dead and live loads in the event that support from Pier 1 lost after an earthquake.