A dam gate in Black River Falls was ripped off by a large tree that was being carried by rushing water Thursday morning.
Utility officials say all of the dam's gates were open at the time, so the damaged gate didn't allow any extra water to rush through.
Despite the failure, officials say the public is not in danger.
"The main protection mechanism is the dike itself, and the National Weather Service has predicted the crest below the level of the dike so as of right now there is no concern for public safety," said Black River Utilities assistant general manager Casey Engebretson.
The rest of the Black River dam is still intact. Officials say they have to wait for water levels to go down before they can repair the broken gate.