Message # 2021-01
Issued: 2:30 p.m., Friday January 29, 2021
Subject: FLOOD WATCH issued for Otonabee River and Jackson Creek.
Issued to: Municipalities of Selwyn, Douro-Dummer, Asphodel-Norwood, Otonabee-South Monaghan, Cavan Monaghan, City of Kawartha Lakes, City of Peterborough and Trent Hills, as well as ORCA’s other partners in flood emergency management.
This FLOOD WATCH is issued to alert municipalities, residents and businesses that flood conditions are a possibility.
Beginning today, Friday, January 29th, and continuing through to Monday, February 01st, the lack of ice cover, turbulent flows, and exposure of water to extreme cold air temperatures will combine to increase the risk of frazil ice generation on the Otonabee River and Jackson Creek. The formation of frazil ice is traditionally observed in these watercourses, which causes flooding concerns.
Frazil ice crystals – 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. Frazil ice may also anchor itself to the bottom of a watercourse and 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.
Residents and businesses in low-lying areas along the shores of the Otonabee River and Jackson Creek are strongly encouraged to keep a close watch for frazil ice generation, accumulation, and jamming, and to take action to limit or prevent damages due to potential flooding.
Water levels can be monitored on-line at:
- Trent-Severn Waterway’s Water Management InfoNet
- Water Survey of Canada Real-Time Hydrometric Data
- Otonabee Region Conservation Authority website
This FLOOD WATCH message will expire MONDAY, February 01st, 2021.
For more information, please contact:
Gord Earle | Otonabee Conservation, Flood Forecasting & Warning Duty Officer | 705-745-5791 x 214