Some residents in Canmore have been forced to leave their homes and others have been told to prepare for possible evacuation.
The town says on its website that power is also out across the community.
It says flood waters have made the banks of Cougar Creek unstable and dangerous.
Some highways and roads around Canmore, as well as Banff and Kananaskis, have been closed because of the water or mud slides.
Environment Canada has issued a rainfall warning for the area, estimating as much as 100 millimetres of more rain could fall in the next two days.