Highlights:

• Special Weather Statement has been issued by Environment Canada calling for heavy rains to begin Friday evening with rainfall totals of 25 to 45 mm possible by Saturday night.
• Risk of ponding and localized flooding due to the rain, throughout the watershed but especially in low lying areas.
• Smaller local watercourses will rise and some will spill their banks.
• Flooding of the Thames River flats from Delaware down to Thamesville.

Message:

A Special Weather Statement has been issued by Environment Canada, which is calling for heavy rains to begin Friday evening. While most of the rain is expected during the evening and overnight, periods of rain could continue throughout the rest of Saturday. By Saturday night rainfall totals of 25 to 45 mm are possible. Due to recent rains, the ground is unable to absorb much more rain, so most of this rain is likely to run off quickly into local watercourses. The Thames River is also still higher than usual for this time of year due to recent rains. Any remaining snow would melt with the warm temperatures and rain, adding to the water running off. The Special Weather Statement also advises about strong damaging winds, especially Saturday afternoon, and a separate message regarding shoreline conditions has been issued.

The amount of rain in the forecast could cause ponding and localized flooding throughout the watershed but especially in low-lying areas. Due to current conditions, smaller local watercourses will respond quickly to the rainfall. Local watercourses will rise and some will spill their banks into low-lying adjacent floodplain areas. The Lower Thames Valley Conservation Authority expects to operate the McGregor Creek Diversion Channel Saturday morning to prevent flooding in the south end of the city of Chatham.

Due to current conditions and the forecast rainfall amounts, flooding of the low-lying river flats adjacent to the Thames River from Delaware down to Thamesville should be expected. In the City of Chatham, the sidewalk along the river in the downtown would be expected to flood over. Water levels would be expected to peak in upstream areas around Delaware on Sunday and work their way downstream over the next few days. If the higher rainfall amounts appear, there could be further impacts around the City of Chatham. Given that the rain has yet to arrive it’s too early to know much more.

Residents are advised to check their properties for potential drainages issue and to clear catch basins and storm sewer inlets of leaves and other debris in order to help reduce localized flooding.

People should take extra caution and avoid the river, ditches, and streams. The combination of slippery banks, and fast-moving cold water can be dangerous. Standing water can also present its own unseen hazards. Children, pets and livestock should be kept away from the water.

Officials will continue to monitor the situation and update this advisory

This message will be in effect until December 13, 2021.

Message Contact: Jason Wintermute ([email protected])