Ice Jams

Ice in a river or stream can pile up causing an ice jam. Water will back up behind the jam and can cause water to spill out of the river and flood surrounding areas.

Ice jams tend to form in places where a river is shallow, or where it goes through twists and turns. Communities in the Nottawasaga Watershed with a history of ice jam flooding include Creemore, Avening and Collingwood.

Flooding can occur even at relatively low flows. Jams can set up in minutes, so there may be little or no time to issue warnings.

That’s why it’s important for residents and emergency services to be on guard in places where ice jams are possible.