20-Mar-2020 27-Mar-2020

This statement is an update to the Flood Outlook Statement issued on March 13th, 2020.

Weather Forecast:
According to Environment Canada, thunderstorms are possible across Eastern Ontario starting on Friday, March 20th, with total rainfall amounts of 10 to 20 mm. Additional rainfall is possible in some areas depending on thunderstorm activity.

Some thunderstorms may become severe along the St. Lawrence River causing wind gusts upwards of 90 to 105 km/h.

Environmental Conditions:
According to the International Lake Ontario – St. Lawrence River Board, Lake Ontario’s water levels are above average for this time of year and will continue to rise next week as a result of Friday’s weather forecast.

Continuing high inflows from Lake Erie into Lake Ontario means that Lake Ontario will continue its seasonal rise headed into the spring and may remain near seasonal highs for the next several weeks. Outflows from Lake Ontario continue to be maximized to the extent possible.

Lake Ontario water levels rose 3 cm this week; 52 cm above average; and 17 cm below the record-high set in 1952.

Levels in Lake Ontario influence levels in the upper St. Lawrence River, particularly from Kingston to Iroquois, including Maitland, Johnstown and Cardinal.

Recent precipitation along with its associated snowmelt may increase water levels and cause flooding along the shoreline or in low lying areas.

Residents are also advised that strong winds may cause large waves, further aggravating water levels which may affect structures close to shore.

Residents are advised to exercise caution when near rivers as the forecasted weather may rapidly increase river flows and cause slippery banks. Parents are encouraged to explain these dangers to their children.

Residents in flood prone or low-lying areas, historically susceptible to flooding, should take the necessary precautions to protect their property, such as:

  • Ensuring sump pump is clear, in good working condition and has a backwater valve on it
  • Portable backup generator and pump
  • Ensuring downspouts are clear and the outlet is at least 3 m from the dwelling
  • Removing or securing items that might float away as flows increase
  • Removing valuable items from basements or lower floors that could be subject to flooding
  • Keep emergency phone numbers handy
  • Familiarize yourself with your municipality’s emergency preparedness plan

This statement is in effect until Friday March 27th, 2020.

SNC monitors water levels and weather forecasts as part of the Flood Forecasting and Warning Program. Updates are provided as conditions change.

The International Lake Ontario – St. Lawrence River Board continues to monitor conditions on an ongoing basis. Information on hydrologic conditions, water levels and outflows, including graphics and photos, are available on the Board’s website at

Please visit for more information. To provide feedback with respect to changes in water related conditions please email, post on our Facebook (/SouthNationConservation) or Twitter (@SouthNationCA).

FOR MORE INFORMATION: Geoff Owens, SNC Regulations Officer,

MEDIA CONTACT: Taylor Campbell, SNC Communications Specialist,

Forwarded to:  All Flood Forecasting and Warning Directory