Lower SF Cottaneva Watershed Habitat Enhancement Design Project

This Project developed 100% Design Plans for 38 engineered and non-engineered LW features along three separate reaches (comprised of 12 features in SF Cottaneva Creek, 21 in Rockport Creek, & 5 in the South Tributary), totaling 1.3mi of stream channel. The 38 features will be made up of 14 whole trees and 103 cut logs for a total of 117 pieces of wood. The LW features will increase flood plain inundation frequency, scour and deepen pools, sort and capture spawning substrate and increase habitat complexity. MLA and ERWIG developed 30%, 65%, and 90% conceptual designs & determined future construction & placement access. MLA completed Final Designs, Basis of Design Report (BOD), and the hydraulic modeling & stability analysis up to the 100%. The final project resulted in the design of 38 large wood features versus 35 large wood features originally proposed for design. Actual stream length measurement where structures were designed ended up being 1.3mi instead of 1.1mi.

This project is the design of salmonid habitat structures. Implementation of the project designs will increased the amount and quality of salmonid habitat. The structures will also provide velocity refugia and will sort spawning gravels which will benefit salmonid survival and reproductive success.