The Merced River below the Crocker Huffman Dam was once a wandering gravel-bedded river with a large and frequently inundated floodplain that supported a variety of flora and fauna. Impacts such as dam construction, flow regulation, diversions, and gravel mining have impaired the river’s ability to support viable populations of anadromous fish.

In conjunction with our teaming partner, Cramer Fish Sciences, PWA is assisting the US Fish and Wildlife Service and the California Department of Fish Game in channel and floodplain restoration for over 2 miles of river, spread over two project areas. For the River Ranch property, PWA is redesigning previously developed plans funded by CALFED for the River Ranch property to better meet project objectives within the overall site and funding constraints. For both sites, PWA is providing full design services for channel and floodplain grading, hydraulic modeling, cost estimating, and preparation of plans and specifications. Our approach for fisheries restoration on the Merced River was to use the available funding resources and existing site constraints to maximize physical habitat while ensuring that designs were geomorphically stable and fit within the overall energetics of the site. A key component of the project has been creating floodplain rearing habitat for juveniles while also ensuring that spawning depths and velocities can be achieved. Construction is anticipated in 2010-2011.