Grand Coulee Dam and completion. Creation of the reservoir forced the relocation of over 3,000 people, including Native Americans whose ancestral lands were partially flooded. While the dam does not contain fish passage, neither does the next downstream dam, Chief Joseph Dam. This means no salmon reach the Grand Coulee Dam. The second large dam downstream, Rocky Reach Dam, has an intricate system of fish ladders to accommodate yearly salmon spawning and migration. The Grand Coulee is an ancient river bed on the Columbia Plateau created during the Pliocene Epoch (Calabrian) by retreating glaciers and floods. Originally, geologists believed a glacier that diverted
Grand Coulee Dam Grand Coulee Dam (not including the Third Powerplant) to be $168 million; its actual cost was $163 million in 1943 ($ in dollars). Expenses to finish the power stations and repair design flaws with the dam throughout the 1940s and '50s added another $107 million, bringing the total cost to $270 million ($ in dollars), about 33% over estimates. The Third Powerplant was estimated to cost in 1967, but higher construction costs and labor disputes drove the project's final cost in 1973 to ($ in dollars), about 55% over estimates. Despite estimates being exceeded, the dam became an economic success,