• Forecasts calling for 20 to 35 mm total rainfall overnight through Saturday.
• Watershed has not yet recovered from the last rain and will likely respond quickly.
• Risk of localized flooding throughout the watershed, especially in low lying areas.
• Smaller local watercourses likely to rise and spill their banks.
Forecasts are calling for rain again, beginning overnight and lasting through Saturday. Total rainfall during this period is currently predicted to be between 20 and 35 mm, with higher the rainfall amounts predicted in the west end of the watershed. The bulk of the rain is predicted to fall Friday afternoon with lingering rain throughout Saturday.
The watershed has not had a chance to dry out since the last significant rainfall and is likely to respond more quickly to this rain and more water is likely to run off into local streams than usual. Localized flooding and ponding, especially in low lying areas should be expected. Smaller local watercourses should be expected to rise and by Friday evening some could spill their banks into low-lying floodplain areas. Should the Chatham-Kent area receive the higher predicted rainfall amounts, the Lower Thames Valley Conservation Authority expects to operate the McGregor Creek Diversion Channel to prevent flooding in the south end of the city of Chatham.
While water levels had dropped on most of our smaller local watercourses, water levels on the Thames River have not yet dropped back down from the last rainfall event. Water levels on the Thames River are still falling through Middlesex and Elgin and will rise back up again due to this rainfall, likely to similar levels as just experienced. Water levels on the river around Thamesville only peaked overnight and the river in Chatham is only now peaking from the last rainfall event. Through Chatham-Kent, water levels on the river should be expected to remain high or climb slightly higher. Water levels in downtown Chatham will rise up enough to finish flooding over the sidewalk along the river in the downtown. Water levels on the Thames River should be expected to remain slightly elevated through next week.
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 flooding.
People should take extra caution and avoid the river, ditches, and streams. The combination of slippery banks, and fast-moving 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 November 5, 2021.
Message Contact: Jason Wintermute (email@example.com)