Spring Freshet arriving this Weekend
Flood Watch
2026 Flood Event 3, Bulletin Number 2 (Issued March 6, 2026, at 4:00 pm, valid until March 11, 2026, at 12:00 noon)
The Upper Thames River Conservation Authority (UTRCA) expects most of the remaining snow in the Upper Thames River watershed to melt this weekend, due to the prolonged warm temperatures, rain already received, and forecast precipitation.
Watercourses have been rising throughout the week, with temperatures above freezing most days and 5-20 mm of precipitation measured. More precipitation has been recorded in the southern portion of the watershed than in the north. Forecast rain ranges from 10-30 mm over today and tomorrow, with higher amounts in the south.
The snow survey conducted by UTRCA on Monday, March 2, estimated 70 mm of snow water equivalent in the northern portion of the watershed, with 18 mm in the south. Approximately 5-10 mm has been released into watercourses from the snow since Monday, with the remaining water still in the snowpack.
With today’s warm temperatures and tomorrow’s temperatures potentially reaching 18 degrees C, most of the remaining snowpack will melt and make its way down the rivers and streams over the weekend.
The UTRCA expects peak flows to develop Saturday evening in the upstream areas of the watershed (Mitchell, St. Marys, Stratford, Woodstock, Ingersoll, etc.). The Thames River through London is expected to peak in the early hours of Sunday. Water levels will remain elevated into next week.
While the UTRCA does not expect serious flooding, there is uncertainty in the weather forecasts and in the estimates of remaining water in the snowpack. If the higher forecasts and volumes materialize, most traditional floodplain areas in the watershed will be inundated. Municipal staff are asked to monitor potential drainage problem areas.
The UTRCA is operating its flood control reservoirs at Fanshawe, Wildwood, and Pittock Conservation Areas to reduce downstream flooding. UTRCA officials will be monitoring the situation closely and will update this bulletin if the conditions change.
The public is reminded to use extreme caution near all local waterways. Stream banks may be slippery and unstable, and the water is very cold and fast-moving. Any ice cover will be weakened and unstable. Ice on flood control reservoirs is especially hazardous due to fluctuating water levels.
Stay out of any flooded areas and do not drive through flooded roadways. Caregivers are reminded to keep children and pets away from watercourses. It is not safe to take shelter along riverbanks or in low lying areas that are prone to flooding.