Temperatures will pass the freezing mark at the tail end of this week, melting some of the massive snowbanks littering southwestern Ontario, but the Grand River Conservation Authority says not to expect any weekend flooding.
That’s the good news.
The bad news? This thaw and melt could actually increase the flooding risk for when the big melt does come.
“There’s always a risk of flooding … but this year especially, it’s quite extreme,” says GRCA spokesperson Cam Linwood.
“If we got a rapid melt at any point in time, a lot of the snowpack could disappear very quickly. That would cause a significant issue.”
In addition to the higher-than-average snowfall we’ve seen this winter, Linwood says, the typical January thaw didn’t occur – meaning most of the snow that fell this winter will have to melt all at once.
Temperatures are forecast to hit a high of 6 C later this week.
During some winters, that would mean snow melting into the Grand River and its tributaries – raising water levels, but cutting down on snowbank size.
This winter, local rivers and streams are frozen over – meaning the only place for melting snow to go is deeper into the snowpack.
When the time comes for that moisture-rich snow to melt, riverbanks will swell and areas near water will be at risk of flooding.
“We’re not going to see that happen until we get a significant warm spell,” says Linwood.
The GRCA has emptied its reservoirs to help mitigate the risk of flooding, but for homeowners worried about high water, Linwood recommends clearing storm drains.
“We certainly want to make sure people keep those snowbanks well off those drains, if they can,” he says.
Away from bodies of water, homeowners aren’t immune to the potential for flooding, as melting snowbanks could seep into basements.
Lauren Bell, a manager at Swanson’s Home Hardware in Kitchener, says homeowners should make sure to clear snow away from windows, doors and window wells – and make sure indoor equipment is in working order.
“Check your sump pump. Go into your basement and make sure that it’s working properly,” she says.
Homes particularly at risk could even benefit from the installation of a second sump pump, Bell suggests.
