Box Canyon Dam Total Dissolved Gas and Fish Passage Modeling

CLIENT: Pend Oreille Public Utility District

NHC was selected by the Pend Oreille Public Utility District to construct and test a physical hydraulic model of the Box Canyon Hydroelectric Facility. As a condition of the District's new Federal Energy Regulatory Commission (FERC) license for the project, the District is required to provide downstream fish passage and reduce total dissolved gas (TDG) in the tailrace.

NHC designed, built, and tested the 1:40 scale model which included approximately 1,000 ft upstream in the forebay, the powerhouse and spillway, and approximately 1,500 ft downstream in the tailrace. The model will be used to test several TDG abatement concepts, including a "gate-in-gate” concept, and various upstream and downstream fish passage facilities.