CRCA Downgrades Lake Ontario & St. Lawrence Flood Warning to Watch

Published on: 2019/08/07 - in Releases

RELEASE — The Cataraqui Region Conservation Authority (CRCA) has downgraded its Flood Warning Statement today to a Flood Watch for Lake Ontario and the St. Lawrence River.

The International Lake Ontario – St. Lawrence River Board (ILOSLRB) is reporting a lake-wide water level of 75.64 m, as of August 5, about 28 cm below this year’s peak of 75.92 m, last recorded June 15. Water levels have been slowly declining for several weeks and Lake Ontario outflows remain at a record-high of 10,400 metres3/second. This outflow level has been on going since June 13 and is the equivalent to outflows released during the summer of 2017.

The ILOSLRB, who manage Lake Ontario outflows, states that, “Levels are expected to continue to decline this week, however, there remains a risk of flooding and high-water impacts during periods of active weather.”

The current water levels measured at Kingston and Brockville of 75.58 metres and 75.15 metres respectively, are still well above average (average annual peak on the Lake is at about 75.0 m in June), but also considerably lower than the highs experienced in June of this year. Kingston saw a peak of 75.88 m on Lake Ontario on June 14. Brockville saw a peak of 75.61 m on St. Lawrence River on June 3. The 2019 peaks represent increases of several centimetres over those seen in 2017.

What this means in simple terms is that water levels, measured in Kingston and Brockville, have fallen at least 30 cm from their peaks in June. Though declining steadily, high water levels will persist for weeks to come. Accordingly, ongoing localized flooding and erosion impacts are now less disruptive than those experienced in June.

The CRCA is urging residents to take care along the shoreline and on the water as levels decline further. Unsafe/unstable banks have been reported due to recent erosion, high water and wave action has deposited debris along shorelines and beaches, and floating debris could cause hazardous conditions for boaters.

A Provincial Flood Watch Statement for Lake Ontario was also issued today by the Surface Water Monitoring Centre (SWMC) of the Ontario Ministry of Natural Resources and Forestry. This Provincial Flood Watch will be in effect until (or updated before) Sept. 8, 2019

Residents in flood prone and low-lying areas should continue to pay attention to forecasts for approaching storms with high winds from the southeast, south and southwest.

If you witness flooding and require assistance your first point of contact is the local municipality. CRCA does not provide sandbags. However, information about where to purchase sandbags is provided at Residents are reminded that it is the property owners’ responsibility to properly dispose of sandbags and sand, which is considered hazardous waste, and any other debris that may have been deposited along the shoreline.

Any work along shorelines (e.g. placement of fill, armour stone, etc.) will require a permit from the CRCA. Call our office or visit our website for further information.

CRCA appreciates feedback from the public and municipal staff detailing flooding and erosion impacts. Please report observations on the online form at

Staff will continue to monitor ILOSLRB forecasts, SWMC Provincial Statements, and local water levels, and update CRCA messaging as needed. This Flood Watch Statement will remain in effect until (or updated before) 11:59 PM Sept. 4, 2019.

For further information on water levels, wind and wave forecasts, and Provincial flood messages visit

See below for watershed conditions terminology:

Normal: No flood conditions exist
Flood Watch: Flooding is possible in specific watercourse or municipalities. Municipalities, emergency services and individual landowners in flood-prone areas should prepare.

Flood Warning: Flooding is imminent or already occurring in specific watercourses or municipalities. Municipalities and individuals should take action to deal with flood conditions. This may include road closures and evacuations.

Photo: Wikimedia Commons (pd)