Mixed Sand and Gravel Beach Design and Construction for Habitat Restoration

A mixed sand and gravel beach 1,100 feet (335 m) in length was designed and constructed during 2005–2006 in Puget Sound as beach restoration, and is being monitored for changes in sediment distribution and profile shape. The beach is to function as improved habitat specifically for salmon, provide public access to the shoreline, and to control erosion of backshore fill. The beach was designed to mimic to the extent feasible the beach face slopes, elevations, and materials of a natural Puget Sound shoreline. Design beach dimensions and morphology were patterned after those of beaches documented at other Puget Sound locations. Forebeach material size gradation was designed from published relationships and judgment based on measured gradations at beaches having similar wave exposure and habitat as targeted for the project site. Construction monitoring assured the intent of the design was implemented. Post-construction monitoring has shown that the constructed beach is performing as designed.