Dam Removal / Tidal Estuary Restoration

Bangor Navy Base
Kitsap Peninsula, WA

Geomorphic Assessment/ Stream Channel Surveys/ Hydrologic, Hydraulic and Sediment Transport Modeling/Stream Channel Design

As a mitigation measure the Navy is planning to re-establish two tidal estuary systems to the Hood Canal and Puget Sound, by removing existing earthen fill roadway dams at the Cattail (8.5 acres) and Devils Hole (14.3 acres) lakes. These lakes have been impounded for 70 years capturing the sediment loads from the upstream watersheds. The final project will re-establish two tidal estuaries to their original historic flow patterns and provide spawning and rearing habitat for salmon in the area. HGD provided a base-line geomorphic assessment of the upstream watersheds and followed that work with a hydraulic and sediment transport analysis to predict the channel evolution sequence and resulting sediment supplied to the Hood Canal when the dams are pulled. This information was utilized in the permitting and construction design phases of the project that is schedule to be implemented.

Clients: United States Navy, SAIC, Otak Inc.