The city says some work will start along the north end of Bear Creek Monday.
Crews will be repairing what is called an outfall, a spot where a drain or sewer empties into a body of water.
It is located near Maskowoteh Park at 108 Street and 116 Avenue.
Some trails in that area will be closed during construction, but the playground will remain open.
Levels in the reservoir will be lowered before the work starts.