Streambed Restoration

Knight Foundation Logo

South Bay Clean Creeks Coalition (SBCCC) is excited to announce a new streambed restoration project with the generous support from The Knight Foundation for a section of the Los Gatos Creek. The work is known as gravel augmentation and improves instream habitat for fall Chinook Salmon by adding properly sized gravel to the streambed. The gravel provides a place for the endangered steelhead trout and Chinook salmon to lay their eggs and protects the eggs from changes in water level and currents in the stream.

Los Gatos Creek MapThe first phase of this project will be to assess approximately 800 feet, from below East Campbell Avenue downstream to Highway 17. Natural gravel supply in this channel appears to have incised and coarsened as streamflows have (and continue to) transport available sediment downstream with little or no upstream replenishment. In addition, a concrete grade control structure spans the channel immediately below the East Campbell Avenue Bridge, which functions as a partial / total fish passage barrier. There is also a lot of concrete and other rubble along the banks and in the wetted channel. Collectively, the limited coarse sediment supply and grade control have resulted in degraded endangered steelhead trout and Chinook salmon fish spawning and rearing habitat.

Develop conceptual design drawings
example of creek augmentationThe seond phase of this project will be to prepare a conceptual design showing gravel augmentation locations, estimated gravel volumes, potential access and staging areas, and the associated gravel placement methods (e.g., direct in-channel placement as bars, pool tails, riffles).

In addition, we will conduct a habitat survey in the 1.1 mile reach between East Campbell Avenue and San Thomas Expressway to evaluate endangered steelhead trout and Chinook salmon spawning and rearing habitat quantity/quality, in order to determine opportunities for habitat restoration in this stretch of the Los Gatos Creek.