Sycamore Creek Bank Stabilization Project

Sycamore Creek Bank Stabilization Project

The RCD and the Natural Resource Conservation Service (NRCS) propose to stabilize the channel, bank, and improve riparian habitat along a portion of Sycamore Creek in Santa Clara County, California. Sycamore Creek is a tributary to Uvas Creek, which is designated critical habitat for the South-Central California Coast (S-CCC) steelhead (Oncorhynchus mykiss) Distinct Population Segment (DPS). Streambank erosion along lower Sycamore Creek delivers fine sediment to Uvas Creek, which degrades salmonid spawning habitat. The proposed Sycamore Creek Bank Stabilization Project (Project) would stabilize and revegetate the channel and over-steepened banks along Sycamore Creek to reduce erosion, control the release of sediment and improve habitat for various species that may utilize the riparian corridor. The proposed Project would stabilize the streambanks by grading them to a slope of 2h:1v. Numerous large pieces of concrete riprap and other debris would be removed from the bed and banks. At the downstream end of the Project, about 50 feet upstream of an existing concrete weir, a sub-grade sheetpile wall and boulder weirs would be installed to prevent further incision of the channel. The sheetpile would be located downstream of the boulder weirs and would not be visible at the surface or active unless the existing concrete weir were to fail. A series (5) of rock vortex weirs would be constructed in the channel immediately upstream of the sheetpile wall. The rock weirs would act as local grade control features and create a series of step-pools. A 12-inch layer of native stream substrate (gravel/cobble) would be placed in the channel bed throughout the Project reach. The entire riparian area would be revegetated with the application of native seed and installation of woody shrub cuttings and container plants.

Morgan Hill

Santa Clara