City - Coulee Dam State - WASH Country - United States
About
Sometimes the water is run over the dam. This doesn't last long or for some hours. In the past they have found out that the water gets supersaturated with nitrogen and kills the fish downstream. Basically it takes the oxygen out and the fish can't breath. This usually happens in the spring for spring run off. There are barriers on top of the spillways that open up and release up to a foot of water.