An oncoming storm expected to hit Manitoba throughout the weekend could push floodwaters to 2009 levels, the province says.
On Friday, Fisaha Unduche, executive director of Manitoba’s hydrologic forecasting and water management, said a fourth precipitation system is set to land in the province Friday afternoon.
Unduche said normal precipitation for the entire Red River basin for this time of April is only 28 millimetres. However, the basin average this year is already about 80 mm, which he said is about 300 per cent of normal. The most southern basins are seeing the highest amount of precipitation since 1950.
“It is unfortunate we are monitoring another major system over the weekend, and this system could bring somewhere in the order of 30 to 80 mm of precipitation in southern Manitoba basins,” Unduche said.
“With the ground fully saturated by this time, most creeks and rivers are already full with the previous system and snow melt. This precipitation could just add more water into the system.”
He said because of this, the province has issued a flood watch for most of southern Manitoba’s basins.
Though the exact impact of the system will not be known until after it hits, Unduche said Environment and Climate Change Canada forecasts somewhere between 30 mm and 90 mm around Fargo in U.S. portion of the basin, and about 60 mm in southern Manitoba.
Unduche said based on the forecast, preliminary indications predict flood waters could reach 2009 levels – which was the worst flood since 1997.
He said this year, water flows could reach between 78,000 and 98,000 Cubic Feet per Second (CFS) in Emerson, and 90,000 to 115,000 CFS in Ste. Agathe. In 2009, Unduche said peak flows in Emerson were around 87,000 CFS and in Ste. Agathe were 91,000 CFS.
He said despite this, the levels will be well below the community flood protection levels, which are two-feet above 1997 levels.
He said peak levels are expected in Emerson between May 7 and May 9 and could remain as late as May 14.
With the added precipitation, the risk of moderate to major flooding remains for the Red River basin.
“Over 20,000 sandbags, sandbagging machines have been delivered to communities who needed them,” said Johanu Botha, assistant deputy minister and head of Manitoba’s Emergency Management Organization.
He added the province is supporting evacuation planning and pumping operations.
“Overall, our emergency response system has ramped up and we are well positioned to respond to the events that might come our way,” he said.
Botha said the flood levels may result in dozens of evacuations, however he said this will mostly be due to flood waters restricting access to communities. Transportation and Infrastructure Minister Doyle Piwniuk said so far six communities have declared local states of emergency due to the flooding.
“W’re always prepared for the worst, but hoping for the best,” Piwniuk said. “We’re going to be working with all municipalities, all Manitobans to make sure that everybody’s safe, everybody gets assistance that they need.”
Unduche said in the days following the storm, the Red River in Winnipeg could reach 20 feet at James Avenue. However he said with the Portage Diversion and the Red River Floodway in operation the province hopes to keep the levels at 19 feet at James Avenue.
“With the snow melt, the Assiniboine River is under a flood warning already from St Lazar to Brandon. We’re talking about flooding of low lying areas and with no major impacts on properties.”