On July 22, NorthWestern Energy will begin drawing down Black Eagle Reservoir upstream from Black Eagle Dam about 5 feet to repair damage from river debris during the high water in May and June.

Flooding in the Dearborn and Sun rivers in late May sent large floating trees and other debris to the dam, which likely caused the damage.

“The damage did not impact the structural integrity of the dam, but it is making it difficult to seal equipment completely, which wastes water and causes inefficiency,” NorthWestern Energy Hydro Plant Foreman Dereck Besich said in a release.

The reservoir water drawdown project will begin July 22 and continue until July 23. Maintenance work will occur July 24 and the reservoir will be back to full pool by the morning of July 26.

Members of the public should not enter the riverbed. Deep mud, slippery rocks and the short duration of the water drawdown will create safety hazards.

NorthWestern Energy conducted a similar maintenance drawdown at Black Eagle Reservoir in August 2016.

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