ABCA Watershed Conditions Statement - Water Safety - March 22, 2023

Watershed Conditions Statement - Water Safety 

Forecast 30-40 millimetres (mm) of rain this week; significant flooding is not expected

Reminder to use extreme caution around all watercourses:

A pair of low-pressure systems is expected to move into the Province of Ontario today (March 22, 2023), and overnight tonight, that will impact the Ausable Bayfield Conservation Authority (ABCA) watershed area with steady rains and continued warm conditions.

Forecasts for the watershed are calling for daily high temperatures in the range of 7-10 degrees Celsius into the weekend. Rainfall is forecasted to begin late this evening, and last through mid-day tomorrow. Depending on the track of this system, 10-20 millimetres (mm) of rain is expected. Snow surveys conducted this week indicate that, where snow is present, an additional 10-15 millimetres of liquid water equivalent remains in the snowpack. Saturated ground conditions from the rain and snowmelt over the last week will result in a quick runoff. 

Based on current weather and streamflow forecasts, levels in watercourses are likely to approach, or possibly exceed, bank-full conditions by late in the day tomorrow, and Friday on the larger rivers. Minor flooding of traditional low-lying flood plain areas is possible.

Flows will remain elevated into the weekend when a second weather system is expected to impact the watershed area again on Saturday, with an additional 15-25 mm of rain. Flows from this additional rain and runoff would result in minor nuisance flooding again. Slightly higher water levels, similar to river conditions last weekend are possible if we see the higher rainfall amounts.

Residents are reminded to use extreme caution near all watercourses. Slippery and unstable streambanks, and extremely cold and fast-flowing water will combine to create hazardous conditions. Any ice remaining on ponds and reservoirs will be very unsafe.

This message will remain in effect until 12:00 p.m. noon, Monday, March 27, 2023, unless local conditions warrant further updates. The Ausable Bayfield Conservation Authority will continue to monitor watershed conditions and will provide an update if required.

Details also available at www.abca.ca.