Lower Snake River all generating power and a further 4 when it joins the Columbia on its way to Portland and the Pacific. Behind the Granite dam lies a lake of water stretching 39 miles.
The fish are guided into fish ladders that are like the exhibit in the visitor centre below. Fish make their way along an uphill channel with laybys that give them a refuge to rest before swimming on and upwards.
Watching fish use the ladder from inside the visitor centre.
I would love to have gone on the guided tour of the dam that included the power house but the whole site is run by the US Army Corps of Engineers and US citizenship with photo id is a condition of a place on the tour. Jaq and I even had to show photo id just to drive the road across the dam, luckily they accepted my UK drivers licence but warned us not to stop till we reached security on the other side. I stood up with my head through the sun roof to get the lock picture.