Floods, High Water Levels Affected Regions Across Canada Over Long Weekend

Members of the Canadian Forces build a temporary dike with sandbags behind houses on Clayburn Creek ahead of a rainfall warning Environment Canada has forecast for the region, in Abbotsford, B.C., on Nov. 24, 2021. (Darryl Dyck/The Canadian Press)

Regions of Canada are either bracing for floods or already experiencing flooding as warm weather melts the accumulated winter snow. The Weather Network forecast “warmer-than-normal” temperatures for the week of April 10.

Tyler Hamilton, a meteorologist with the Weather Network, said on April 8 that almost every region in Canada was likely to see the thermometer rise due to a ridge of high pressure, except in Atlantic Canada, where a weather system east of Newfoundland is predicted to lower temperatures.

Hamilton said Alberta and Saskatchewan will see temperatures close to 20 degrees, but Manitoba will have stubborn low clouds and a widespread snowpack suppressing temperatures.

Flooded farms along the Trans-Canada Highway in Abbotsford, B.C., on Nov. 22, 2021. (Darryl Dyck/The Canadian Press)

British Columbia

In British Columbia, advisories of high streamflow were issued by B.C.’s River Forecast Centre on April 10, as heavy rain from a Pacific frontal system blanketed the southern interior. Similkameen and Okanagan regions were added to existing warnings affecting Vancouver Island, the Sunshine Coast, Metro Vancouver, and parts of the Fraser Valley.

Vancouver was drenched in rain over the Easter weekend. Environment Canada issued a rainfall warning for the Elk Valley on April 9, warning that the next two days could see up to 50 millimetres of rain, according to the Regional District of East Kootenay (RDEK).

High streamflow advisories are issued when water levels could rise rapidly and flood low-lying areas.

The B.C. south coast is expecting up to 200 millimetres of precipitation, with high water levels in rivers through the North Shore Mountains, Howe Sound, the lower Mainland, the Fraser Valley, and Vancouver Island.

While flows are below normal, the rainfall is anticipated to rapidly increase water levels.

“These rain-on-snow events have a high amount of uncertainty based on rainfall totals, ripeness of the snowpack to melt and the fluctuation of the freezing level,” said the river forecast centre on April 10.

Alberta

In Alberta, the municipal district of Taber issued a flood watch on April 9 stating that warm temperatures were increasing the risk of flooding and that spring runoff had affected roads.

Over the Easter weekend, Taber and the County of Forty Mile warned that spring runoff was affecting multiple roadways in the southeast region of the district.

One section of the road at the intersection of Highway 513 and Range Road 14-3 was underwater on April 8.

“Roads can be washed out and it is dangerous to travel if you cannot see the road surface,” the county warned on April 8. On April 9, the county advised there was a risk of flooding near the main SMRID canal, which the day before had flooded the area one mile north of the Highway 3 canal crossing.

Residents were initially warned to prepare for overland flooding potential, but by April 10 the county said flooding had slowed, and with cooler weather in the forecast, the situation was expected to improve.

Saskatchewan

In Saskatchewan on April 10, the Water Security Agency (WSA) advised the public that ice jams could be expected on Swift Current Creek, the Moose Jaw River, the Qu’Appelle River, and the Wood River following recent rapid melting and runoff.

“Ice jams increase the risk for potential localized flooding as they disrupt normal flows and can cause water to breach embankments,” said the WSA.

The agency said that while ice jams were not uncommon, water flows were higher than predicted or expected to be higher.

WSA diverted water on the Swift Current Main Canal on April 10 to reduce flows through the city of Swift Current. The agency said runoff within headwater areas of the Moose Jaw River basin was also higher than expected.

“Residents are advised to be aware of the potential for ice jamming and possible flooding upstream where it occurs. The public should exercise caution as ice jams can be highly dynamic resulting in rapid changes in water levels—under no circumstances should anyone venture out onto an ice jam,” said WSA.

Ontario

Eastern Ontario saw flood warnings issued by Quinte Conservation, headquartered in Belleville, Ontario, on April 9, for several rivers and lakes. Water levels on the Moira River from Stoco Lake to Corbyville continued to rise and were expected to peak by April 9.

The organization said water levels at Stoco Lake and Moira River in Tweed were close to one-in-10-year flood levels, and with a warm forecast expected, melting snowpack could cause water levels to rise further.

Local municipalities were making sandbags available, and residents in low-level areas were advised to have sump pumps functioning, and secure items in low-lying regions.

Quinte warned the public to avoid open, fast-flowing water and expect ice surfaces to be unstable.

Parts of Ontario are also expected to see temperatures in the 20s this week, according to the Weather Network, but areas along the Great Lakes will be chilly.

Ottawa and Quebec will see warm weather possibly by April 14, said Hamilton.

Halifax

Halifax also saw flooding early in the afternoon on April 10, but not due to weather. Instead, a water main break in the city caused havoc, after a construction company hit a transmission main line in the area, according to Halifax Water.

A resident, Richard Woodbury, posted videos of the flooded Armdale Roundabout, and said water was coming from the grounds of the Nova Scotia Power station.

According to Financial Services Bulletin from McMillan Insurance on April 10, flooding has been the most common and expensive event of weather disasters in Canada, with flooding losses in Canada estimated at a total of $16.4 billion between 2013 and 2017.

The Canadian Press contributed to this report.