The new Alder dam as it looked August 21, 1945.
“Alder was a concrete arch structure, 330 feet high, two miles above the smaller dam at LaGrande. The town of Alder, population 200, was inundated by the reservoir in 1944. Construction was hampered by faults in the bedrock that required more excavation than planned. The labor shortage during the war also slowed progress. The Alder Powerhouse generated 50,000 kilowatts.
LaGrande was a concrete structure 192 feet high that replaced the 45-foot diversion dam. The additional impoundment of water increased the output of the powerhouse by 80 percent to 64,000 kilowatts.”
For more information go to Historylink.org.
Photo courtesy of Pat Van Eaton.
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