Flood Warning (Lake Ontario/Bay of Quinte)

Lower Trent Conservation advises municipalities and the public that the Flood Warning for Lake Ontario and the Bay of Quinte issued on May 9th, 2019 is still in effect.

Water levels on Lake Ontario have been increasing quickly since mid-April and are expected to continue increasing for the next week. The water inflows from Lake Erie have been significantly higher than the outflows from Lake Ontario. This condition, combined with spring freshet flows from local watercourses, has resulted in high water conditions on Lake Ontario.

Outflows from Lake Ontario are being controlled by the International Lake Ontario St. Lawrence River Board (ILOSLRB) due to the flooding situation in the Ottawa River and downstream impacts along the St. Lawrence River. Flows on the Ottawa River are still very high and flooding situations are still present on the Ottawa River and downstream on the St. Lawrence River. Recent dry weather and increased Lake Ontario outflows over the past week have assisted with mitigating the high water situation on Lake Ontario.

Lake Ontario water levels have risen 40 cm since the beginning of May. The water level measured at Cobourg is currently at 75.80 masl (metres above sea level) which is 10 cm above the Lake Ontario 100-year flood elevation of 75.70 masl. Forecasts by the International Lake Ontario and St. Lawrence River Board (ILOSLRB) are indicating that the water levels in Lake Ontario are expected to rise to an elevation of 75.89 masl next week if average precipitation conditions continue. Wetter conditions could lead to higher water levels.

Residents living in low lying, flood prone, shoreline areas should anticipate further water level increases through the remainder of May, and possibly into June if wet weather persists. Additionally, surge related flooding and erosion damages from high waves is possible during periods of strong onshore winds. Residents should pay close attention to weather forecasts for approaching storm systems with high southeast, south or southwest winds.

Property owners are also reminded that any work along the shoreline (e.g. placement of fill, armour stone, etc.) will require a permit from Lower Trent Conservation and should call the office or visit the website ( for more information.

Residents living in low-lying, flood prone areas should take actions to protect themselves and their property. Homeowners affected by flooding should also be aware that electrical, well and septic issues may exist. The public should pay attention to Health Unit guidelines to ensure safe drinking water.

If safe to do so, the public is encouraged to share photos of water concerns in their area via Facebook (@lowertrentconservation), Twitter (@LowerTrent) and/or Instagram (@lowertrentconservation).

Lower Trent Conservation monitors water levels and weather forecasts as part of its flood forecasting and warning program. If you have concerns about water levels, please contact Lower Trent Conservation at (613) 394-4829.

An update to this Flood Warning for Lake Ontario/Bay of Quinte will be provided on, or before, Friday, June 7th, 2019. Additional statements will be issued if conditions are expected to change significantly from this outlook.

A Flood Warning is issued when flooding is beginning/occurring or when more serious flooding is possible. A Flood Warning requires action that may include the activation of the municipal flood emergency plan, warning residents or businesses in specific affected areas, and in some cases evacuation.