Three Rivers Diversion Dam

During a fish migration period, this Oregon Fish and Wildlife coastal project required the diversion of an average 90 cubic foot per second river through a 42-inch HDPE fusion welded pipe. This was an environmental challenge as salmon were climbing a portion of the diversion dam as the line was being laid, also the excavation work in the river itself.

Environmentally challenging as well as demolishing 300 cubic yards of reinforced concrete, installing 600 cubic yards of reinforced concrete for the new fish ladder and adjustable weir structure; and installing 64 Obermeyer inflatable weir gates with associated electrical; compressor; piping; and controls. The in-water work season was also restricted to June 21 through September 15.