While the Chatham-Kent region is again seeing dangerously high waters early in the season – a grim reminder of last February’s widespread flooding – officials here aren’t expecting a rerun of that nearly record-setting disaster.
Still, conservation authority and municipal officials remain wary, exercising the necessary precautions given the unpredictability of the ice jams along the Thames River and a forecast that includes heavy rains.
“Unfortunately, this is ice-jam stuff and it’s very, very difficult to predict,” Jason Wintermute, the authority’s water management supervisor, said Thursday. “It depends on how much flow can pass underneath the ice. We do our best based on the ice jams we’ve seen in the past, but every ice jam is different.”
The Lower Thames Valley Conservation Authority formally issued a flood warning Thursday morning for the Thames River in Chatham. However, the flooding so far is more localized – and with lower levels – than last year’s state-of-emergency deluge, which was caused by warmer spring-like temperatures, melting snow and heavy rains.
This time, the ice jam that formed downstream Wednesday night and is now lodged around the Prairie Siding bridge, about 12 kilometres southwest of Chatham, is the main culprit, conservation authority officials said.
“The ice jam has not moved at all,” Wintermute said. “We’ve had people out there three or four times today.”
That jam – huge floating chunks of ice and debris – has caused the river’s water levels to rise, meaning the flooding of the basements of businesses along King Street in Chatham’s downtown is unavoidable.
Wintermute said the water levels are currently 4.15 metres above normal, and are expected to reach a peak of 4.65 metres. Last year’s levels were 5.25 metres above normal.
“We’re expecting a couple of feet lower than what we had last year,” Wintermute said.
Trevor Terfloth/The Daily NewsThe Lower Thames Valley Conservation Authority has issued a flood warning for Chatham and downstream areas. An ice jam is currently lodged to the west around Prairie Siding.
Because of issues with traditional methods of dislodging these ice jams – both dynamiting and tug boats are ineffective and potentially dangerous, the conservation authority said – other methods are being used to mitigate the impact of the rising river waters.
The conservation authority is now operating its Sixth Street dam and pumping station, which is expected to protect the south end of the city of Chatham on McGregor Creek from flooding.
Chatham-Kent fire Chief Bob Crawford said the municipality is taking the necessary precautions, calling it a “dynamic and changing” situation.
“There’s no disaster. There’s no state of emergency,” he said after a Thursday afternoon meeting with municipal officials at Chatham-Kent’s civic centre. “The mayor decided that he would prefer to be prepared. We’re monitoring and we’re preparing, and we’re planning to see how we’re going to respond.”
Firefighters and economic development personnel trekked door to door Thursday, checking in on downtown businesses and providing updates.
Trevor Terfloth/The Daily NewsChatham-Kent firefighters have been scouting out the area and checking in on downtown businesses.
Chatham-Kent Mayor Darrin Canniff said safety remained the priority.
“We want to emphasize, stay away from the river,” he said. “It’s a common-sense thing. There’s heavy flows moving there and you just never know. The banks might be weak. We don’t want anybody falling in.
“Is it going to be like last time? We don’t expect it to be.”
The last time there was ice jamming at Prairie Siding with similar flows in the river, water levels in Chatham rose an additional 0.7 metres from where they were Thursday morning, the conservation authority stated. This would create water levels similar to those seen during floods 2008-09 and 1985.
However, there was a significantly greater thickness of ice during the 1985 ice-jam flood, the Lower Thames River Conservation Authority stated.
If such water levels are reached because of changing conditions, this could again mean expansive flooding near Chatham’s downtown, as well as additional impacts along the downstream portions of the river through the Raleigh and Dover areas and into the town of Lakeshore.
Thomas Kelly, the municipality’s general manager of infrastructure and engineering, said his department works closely with the conservation authority and will determine the next steps based on all of the variables, including river flows and weather.
Last year’s flooding was far more widespread, resulting in evacuations of the affected areas.
Noting there were definitely hardships, Crawford called last year’s disaster a valuable experience for crews.
“We learned an awful lot how to respond, how to communicate, how to collaborate between our departments,” he said. “This is a co-ordinated team approach and it’s a group of highly skilled professionals.
“We’re very hopeful this is going to be a non-event. The jam will move downstream, the rain doesn’t come, and the waters recede. We do prepare for the worst and hope for the best.”
Area residents are urged to pay close attention to local conditions and be prepared should water levels exceed the flood protections.
Residents in the south end of the city of Chatham should also be mindful of conditions.
Weather forecasts for the afternoon and evening are calling for 15 to 20 millimetres of rain, with the added potential for thunderstorms.
As water levels are high, excessive rainfall could lead to localized flooding upstream in the areas along McGregor and Indian Creek currently protected by the Sixth Street dam.
BY THE NUMBERS
Thames River in Chatham
Currently: 4.15 metres above normal
Expected: 4.65 metres above normal
2018 flood: 5.25 metres above normal
Forecast: 15-20 mm rain
– Figures from the Lower Thames Valley Conservation Authority
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