In all the coverage I and other staff members did of Gavins Point Dam this summer during the Missouri River flooding, I don’t recall hearing or reading anything about power output being down. (Of course, that could just be because of my bad memory.) I guess there’s always some stone that has been left unturned.
Here is an article I came across today on the subject from Dar Danielson at Radio Iowa:
Record water releases from the main Missouri River dams over the summer led to record amounts of electricity being produced, at least from most of the dams.
Dave Becker, operations manager for the U.S. Army Corps of Engineers at Gavins Point Dam on the Nebraska-South Dakota border, says flooding below the dam actually caused their power output to fall.
“We rely on water pressure to make our turbines go around and normally, we have about 50 feet of head,” Becker says. “This year, we had about 35 feet of head because the lake level stayed about the same level. We don’t store a lot of floodwater here at Gavins Point, but our river level, below the dam, raised by about 15 feet.”
Becker says that lower water pressure and other issues led to a big drop in power production from the three massive generators. “They were chugging along, lugging a bit this summer,” Becker says. “We were generating on the order of a quarter of the power we would normally generate. Plus, it was more difficult for us to get cooling water (for the generators) out of this lake during the flood because there was so much debris in it.”
He says the strainers usually have to be cleaned twice a year but during the flood, they had to be cleaned four times a day. Becker says they had to make mechanical adjustments to the turbines, which are more than 50 years old. He says two of the three units were kept running this summer and the third should be back online soon. Becker says as river levels fall, their power production will rise back to near-normal levels.