flood watch

May 11, 2020

Cataraqui Conservation has updated its Flood Watch for Lake Ontario and the upper St. Lawrence River today.

While water levels are higher than normal for this time of year, it is predicted that any increases in overall levels will be minimal. Levels are not expected to reach the historic levels experienced over the past few years.

The International Lake Ontario – St. Lawrence River Board (ILOSLRB), which manages Lake Ontario outflows at the Moses-Saunders Dam in Cornwall and develops water level forecasts, is forecasting (as of May 7) that under seasonally normal weather and water supply conditions, Lake Ontario is expected to peak below 75.4 m and begin its seasonal decline in the coming weeks. Higher peak levels are possible if wet conditions occur, but water levels are expected to remain well below the record-highs of 2017 and 2019 (75.88 m and 75.92 m, respectively).

The current level on Lake Ontario reported by the ILOSLRB is 75.39 metres above sea level (masl) as of May 6, 0.38 metres above average for this time of year, 0.38 m below the record high for this time of year set in 2017, and roughly 0.35 m above typical summer peak. The near record-high level of Lake Erie, which flows into Lake Ontario, will prevent any rapid lowering of Lake Ontario levels.

Publicly available water level forecasts are updated weekly by ILOSLRB (links provided further down this statement).

Widespread flooding is NOT expected at this time. This Flood Watch provides advance warning to municipalities and residents in flood prone and low-lying areas to the potential for localized flooding and erosion impacts.

Residents in flood prone and low-lying areas should continue to pay attention to wind and wave forecasts for approaching storms with high winds from the southeast, south and southwest, as these are the conditions when the probability of localized impacts (e.g. flooding & erosion) is increased.

If you witness flooding and require assistance, your first point of contact is the local municipality. Cataraqui Conservation does not provide sandbags. However, information about where to purchase sandbags is provided at www.crca.ca/flood. Residents are reminded that it is the property owner’s 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 Cataraqui Conservation. Call our office or visit our website www.crca.ca for further information.

Cataraqui Conservation appreciates feedback from the public and municipal staff detailing flooding and erosion impacts. Please report observations on the online form at www.crca.ca/flood.

For further information on water levels, wind and wave forecasts, and Provincial flood messages visit www.crca.ca/flood.

For information directly from the International Lake Ontario – St. Lawrence River Board visit:

  • Main website - www.ijc.org/en/loslrb
  • 2017 and 2019 High Water Events page – www.ijc.org/en/loslrb/watershed/2017-and- 2019-high-water-events
  • Current conditions - https://www.ijc.org/en/loslrb/watershed/current-conditions
  • Water level forecasts - https://www.ijc.org/en/loslrb/watershed/forecasts

Staff will continue to monitor International Lake Ontario St. Lawrence River Board water level forecasts, Surface Water Monitoring Centre Provincial Statements, and local water levels, and update Cataraqui Conservation messaging as needed. This Flood Watch will remain in effect until (or updated before) 11:59 PM July 30, 2020.

See below for watershed conditions terminology:

Normal: No flood conditions exist

Watershed Conditions Statement – Water Safety: High flows, unsafe banks, melting ice or other factors that could be dangerous for recreational users such as anglers, canoeists, hikers, children, pets, etc. Flooding is not expected.

Watershed Conditions Statement – Flood Outlook: Early notice of the potential for flooding based on weather forecasts calling for heavy rain, snow melt, high wind or other conditions that could lead to high runoff, cause ice jams, lakeshore flooding or erosion.

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.