When planners first began to understand the potential power of the Columbia River, they worked hard and making sure every kilowatt of electricity was wrung from every last drop of water the flowed from the Rocky Mountains in Canada to the Pacific Ocean.
Canada was mostly left out of this planning, but that’s another story.
Dams were planned for the mainstem Columbia and Snake rivers as well as the powerful tributaries by many organizations. The political battles could almost be considered epic, except that we almost never hear about the losers and the dams they had planned.
Of special note, the Hells Canyon Complex (https://www.nwcouncil.org/history/HellsCanyon) was particularly fought over by conglomerates from Washington and Idaho as well as the U.S. Army Corps of Engineers. High Mountain Sheep-Pleasant Valley Dam and Nez Perce Dam were two planned for the Salmon River area that were never built. The battle went to court with the Dept. of the Interior fighting the Federal Power Commission to stop construction of the two dams.
The Hanford Reach of the Columbia River was targeted to be home to the Benjamin Franklin Dam (http://www.historylink.org/index.cfm?DisplayPage=output.cfm&file_id=7440). Fortunately, all but Corps of Engineers planners thought the dam was a bad idea. Too much would have been lost had the dam been built near Pasco, Washington, not to mention the even closer proximity of water to the nuclear storage tanks.
If you would like to learn more about the dams that were or were not built in the Columbia River Basin, contact the StreamNet Regional Library for assistance and information. We can guide you to some excellent reading material or the correct District office of the Army Corps of Engineers.