Art Anderson Associates is participating in the largest tidal wetland restoration project on the west coast, located at the Don Edwards San Francisco Bay National Wildlife Refuge. About 85% of these historic marshes were lost in the last century due to urbanization or being diked off for salt production. In 2003, the US Fish and Wildlife Service and California Department of Fish and Game acquired 15,000 acres of these salt ponds for restoration, an area the size of Manhattan. Part of the restoration plan involves breaching levees to allow tides to flow back into the ponds, which will allow them to become natural marshlands once again. While this will do much to restore habitat, it presents challenges for flood control.

Our scope of work on this design-build project involves design development and construction documents for flash weirs and water control structures at the Ravenswood Pond SF2. This 240-acre pond will be reconfigured to create islands for nesting birds and shallow water habitat for shorebird foraging. Two water control structures, two steel-frame wildlife viewing platforms, and numerous berms and islands will be constructed, in addition to raising levees by 1-2 feet. The water control structures are being constructed to achieve target water depths, adequate flushing to ensure water quality, protecting the perimeter levee and bike path from flooding and habitat management flexibility.

We are also working with the contractor, Triton Marine Construction, to identify and capitalize on value engineering opportunities. Some of these opportunities have included substituting recycled concrete as fill, substituting a wood valve control structure for a concrete vault, and using precast, prestressed concrete piles instead of plastic-coated wood piles. So far in the project, we've identified $135,000 in project cost savings using value engineering.

The SF2 Project was featured in a paper and presentation for the ASCE PORTS 2010 Conference, held in April 2010.  Patrick Vasicek presented the project on behalf of he and the rest of the paper's authors (James Levey, PhD, PE; Herb Fricke, PE; Jon Archer, PE; and Rob Henry, PE).  Read the PORTS 2010 Paper (PDF).  View the PORTS 2010 Presentation (PDF).