Otonabee Conservation has issued a flood watch for Otonabee River, Jackson Creek and all other flowing watercourses in the Region
Municipalities of Selwyn, Douro-Dummer, Asphodel-Norwood, Otonabee-South Monaghan, Cavan Monaghan, City of Kawartha Lakes, City of Peterborough and Trent Hills, and ORCA’s other partners in flood emergency management are included in the flood watch.
The current extreme cold air temperatures can combine with a lack of ice cover and turbulent flows in area rivers, streams, and creeks to cause the generation of frazil ice which can lead to flooding. Extreme cold weather causing flooding has historically been observed in Jackson Creek and the Otonabee River but is possible anywhere that watercourses are uninsulated by ice cover and where flows are turbulent due to rapids or water falling over dams or waterfalls
Frazil ice – a kind of slush ice - can form when cold air temperatures and wind chill combine to cause surface water temperature to be super-cooled (i.e., cooled below the freezing point), but the super-cooled water is unable to form a solid cover of ice because of fast moving water. As frazil ice flows downstream it will eventually come to rest against obstructions (e.g., islands, bridge piers and abutments), in low velocity areas (bends and slope reductions) or in areas of channel constrictions. Where it comes to rest, it will accumulate.
Where frazil ice accumulates, it is likely to cause a restriction of water flow downstream, thereby resulting in a rise of water, and possibly flooding, behind the frazil ice jam.