To make repairs to the Sylvan Dam, the Crow Wing River has been lowered 5.5 feet.
Minnesota Power, the company that operates the dam, is installing a 140-foot rubber bladder that will allow for better control of water levels, said Terry Johnson, MP spokesman.
Previously the dam had "flash boards" that were adjusted up or down to control flow. The new bladder will be inflated to slow the flow and deflated to increase it. One person can handle the job instead of a crew.
"We had a 30-foot piece of bladder on that same dam and it worked well," Johnson said. "It's more efficient, especially during times of high flow."
The bladder system is unique to dams in this area, Johnson said. Gates on other dams are operated with remote controls, which are more expensive to install and maintain than a bladder system.
Construction work continued Tuesday on the Sylvan Dam, which holds the Crow Wing and Gull River water level in the fisherman's bridge area west of Baxter. The spillway is being renovated by Minnesota Power to include technology that will allow smoother control of the water levels in the future. (Dispatch Photo by Steve Kohls)
After getting the necessary permits from the Federal Energy Regulatory Commission, Minnesota Power shut all but one gate of the dam on Aug. 24. Work on the dam began the next week. For several miles behind it as much as 60 feet of what once was river bottom is now exposed.
The new bladder will take about six weeks to install at a cost of $150,000, Johnson said.
"Unless there's a problem we won't have to do this again," Johnson said.
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