Sudden heavy downpour floods parts of southwestern Manitoba

A hot and muggy evening became a sudden monsoon in parts of southern Manitoba on Tuesday, with sideways rain, golf-ball-sized hail and flooding.

“It was very sudden and unexpected. We all just got very soaked. It caught us all off guard,” said Cori Bezan, who had headed out for dinner at the Winkler golf course as the clouds rolled in.

“By the time we sat down to dinner, the temperature was just dropping and the wind was picking up and all of a sudden we could just see a sheet of rain advancing over the golf course.”

Officials at the golf course blew a horn to call in all golfers “and within moments, it was just absolutely pouring,” Bezan said.

“The rain came in super, super fast. There was hail, there was wind [blowing] sideways in sheets of rain. It was just crazy.”

The most intense part of the storm lasted about 10 minutes, though rain was steady for some time afterward, she said.

Bezan heard from a number of people and read social media posts saying they couldn’t get good readings on their rain gauges because so much of the rain was going sideways.

“A few people joked, ‘Oh man, we had our rain gauges set up the wrong direction,'” she said.

Official readings from Environment Canada say Winkler received 67.7 millimetres of rain over the span of two hours but the majority of that — 57.3 mm — fell in one hour.

According to city manager Jody Penner, that 68-ish amount was in the northern part of the city. The south was hit much harder, with up to 114 mm, he said.

“That’s a lot of rain,” he said. “Our initial look at some of the numbers show us that it’s in excess of a one-in-100-year event.

“The problems came quite quickly and were widespread,” he said, and the municipal drainage system just couldn’t keep up and became overwhelmed.

Ginny Andries posted this image of hailstones in Deloraine on Twitter. (Ginny Andries/Twitter)

A number of Winkler businesses also experienced fairly significant flooding, with water running through their front doors, Penner said.

“So we feel for them. It’s just an event that doesn’t happen very often.”

There have been reports of some basements flooding but the full extent of that is not yet known, Penner said.

Gretna, about 32 kilometres southeast of Winkler, received 58.9 mm and Morden, about 10 kilometres east of Winkler, recorded 46 mm.

Some areas just to the north of Morden had much as 97.7 mm due to isolated intense rain in thunderstorms. Wawanesa, further west in southern Manitoba, received 44 mm, with wind gusts hitting 98 km/h.

Winnipeg also caught some of the rain, but only the edge of the storm. Just one to two millimetres were recorded in the city, located about 85 kilometres northeast of Winkler.

The City of Winkler posted this message on its social media channels Tuesday night as the rain was coming down. (City of Winkler/Facebook)

By the time Bezan left the restaurant after dinner, water was above most culverts and across many roads. Emergency crews were blocking off the worst streets and redirecting traffic. 

“There were stalled cars everywhere,” Bezan said.

Limit water use

Penner said crews tried to close off as many roads as possible, “but there was just too many that were flooded to really block all of them.”

The drainage system was able to catch up a little overnight so that most roads were drained and clear by Wednesday morning, he said.

“Our lift stations [pumping stations that move wastewater from lower elevations to higher ones] still struggling to keep up, so that’s why we’ve asked residents to just limit water use for today to give us a chance for the lift stations to catch up,” Penner said.

“When we have an event like this, there’s a lot of infiltration of the groundwater into the sewage system, and so that’s kind of another thing that overwhelms the sewage system separate from the storm-water drainage.”

There are a few things people can do to help out, including delaying laundry for another day, taking shorter showers, limiting flushing of toilets where possible “and if people have some pumps, don’t drain them into the sewer system — make sure those are going outside,” Penner said.

“We’re hoping by the end of today that our systems are caught up, barring any more rain.”

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