The trash racks and the fish screen frames were installed to restore endangered smolt (juvenile salmon and steelhead) to the Columbia River and Snake River watersheds. The previous system allowed smolt migrating to the ocean from their spawning nests to pass through generators. These generators killed approximately 77 percent of the smolt. 

The new fish screens and trash racks force the smolt down in the water to a diversion channel, which redirects them to a pipe going around the generators. Since the installation of the new frames and racks, the kill rate of the smolt has been reduced to approximately 12 percent. An aggressive environment demands the best possible corrosion prevention system available. Hot-dip galvanizing was the natural choice, considering the seriousness of this application. Each fish screen and trash rack had to be handled and inspected with extreme care. Since the galvanized steel is in direct contact with an endangered species, it was a natural choice because the coating is non-threatening to both aquatic life and water quality.