Grand River Conservation Authority - Flood Message #1 – High Lake Erie Level – Flood Warning

The GRCA is issuing a High Lake Erie Level Flood Warning Message. The Watershed Conditions Statement for Lake Erie remains in effect.

Environment Canada has issued a Wind Warning advising of a low pressure system tracking across southern Ontario tonight. This system will bring strong southwest winds of 70 km/h gusting up to 100 km/h, before easing on Friday afternoon. Rainfall in the 15-25 mm range is also forecast for the Haldimand County overnight and into Friday morning.

The current Ministry of Natural Resources and Forestry (MNRF) surge model forecast for the eastern end of Lake Erie is indicating a rise in lake levels of 2.53 metres (8.3 feet) above chart datum of 173.5 m IGLD85 at the gauge in Port Colborne. The peak above critical level is forecast to occur mid-day Friday. Uncertainty remains in the height of the Lake Erie surge based on current forecast models. The GRCA will continue to monitor this event and issue updated flood messages as necessary.

The MNRF forecast is predicting the following in the vicinity of Port Maitland:

Lake Erie current elevation at Port Maitland: 174.6 m (IGLD 1985)

Lake Erie estimated to peak at: 176.03 m (IGLD 1985), excluding waves

Lake Erie Expected time of peak: Friday, March 25 at 12 p.m.

Critical Level: 175.5 m (IGLD 1985)

Forecast (estimated) Peak Lake Level: 0.53 m above the critical level, excluding waves

Flood Zone Area of Impact: Zone 3 flood zone along Lake Erie shoreline

The Haldimand County Flood Coordinator is requested to warn affected residents and businesses up to and including Lake Erie Flood Zone 3, along the Grand River downstream of Dunnville Dam, in the community of Port Maitland, and along the lakeshore and to monitor roads and implement closures as necessary. Waves of up to 1.75 metres are forecast to accompany this event. Given the uncertainty that remains in this forecast, the public is advised to familiarize themselves with flood warning zone mapping available on Haldimand County’s website.

The public is reminded to stay away from the Lake Erie shoreline due to the potential for strong wave action and elevated water levels. Parents are reminded to keep children and pets away from these areas. This message is in effect until 6:00 p.m. on Friday, March 26, 2021 and will be updated as the event draws closer.

Lake levels are updated each hour on the GRCA website at www.grandriver.ca under the river data section.

More information

• For more information on flows, weather and reservoir conditions see the River Data section of the GRCA website.
• For more information on Lake Erie levels, see the Lake Erie page of the GRCA website.
• Safety information for parents and children is available in the GRCA’s River Safety Rules booklet.
• More information on the flood warning system is available on the GRCA website.
• Receive GRCA flood messages by e-mail by subscribing through the GRCA website.
• Follow GRCA flood messages on Twitter at grca_flood_msg.
• More information about how the GRCA manages floods is available in the Flooding section of the website.