The City of Winnipeg continues to prepare to fight a spring flood as large as the 1997 Flood of the Century even though provincial forecasts suggest it's more likely the Red River will rise to levels similar to those experienced during the 2009 flood.
The city has started filling the first of 1.8 million sandbags it will need as part of an effort to protect 690 low-lying properties that sit from water levels as high as 25 feet above the normal winter ice level at the James Avenue monitoring station -- a level close to the 1997 peak of 24.5 feet.
A flood that large is possible in the event another 60 centimetres of snow falls on the Red River Valley this spring, provincial flood forecaster Phillip Mutulu said Thursday. There's a one-in-10 chance of this happening, Mutulu said.
Barring a late-season blizzard or series of major snowfalls, odds are practically even the Red will peak at levels between 21 and 23 feet above normal winter ice levels at James Avenue, which is similar to the 2009 flood peak of 22.6 feet.
"That's still a very significant flood," said city flood-protection engineer Grant Mohr.
The city prepares for the worst possible scenario, Mohr said.
Nonetheless, letters have already been sent to the owners of all 690 properties that would be affected by a 25-foot flood, Mohr said. The city will begin surveying the elevation levels of those properties on March 7 and the decision to sandbag specific properties will be finalized after the province issues another flood outlook during the third week of March, Mohr said.
Once the breakup begins, operational flood forecasts will then be issued -- daily, if need be -- to keep up with changing conditions, he said.
The Red is expected to break up in early April this year, barring any unusually warm or frigid weather this March, Mohr said. That's several weeks later than the 2009 flood breakup but weeks earlier than the 1997 breakup.
On average, the Red is breaking up three weeks earlier than it did in the late 1960s, said Steve Topping, executive director of Manitoba Water Stewardship.
The City of Winnipeg has already filled 25,000 sandbags, utilizing one machine, said emergency preparedness co-ordinator Randy Hull. Two more machines will begin working on Monday, granting the city enough time to fill 1.8 million sandbags over the next five to six weeks.
The city filled twice as many sandbags in 1997. Since then, clay dikes have been built around homes in low-lying areas such as Turnbull Drive in St. Norbert, reducing the need for sandbags.
The city also plans to raise nine kilometres of primary dikes using Hesco bastions -- square wire-and-fabric bags that can be filled with sand. Fargo-Moorhead used Hesco bastions successfully during spring floods in 2009 and 2010, Mohr said.
Winnipeg will deploy these bags along Scotia Street in the North End, Kildonan Drive in East Kildonan, Glenwood Drive in Elmwood and Lyndale Drive in Norwood.
The city has ordered 25 more tractor-mounted portable pumps to deal with overland flooding, bringing the total complement to approximately 50, Mohr said. The city also has 35 permanent flood-pumping stations.
The cost of the flood fight is "still a moving target" but a projection has been factored into the city's 2011 operating budget, said city council finance chairman Scott Fielding. The budget will be tabled during the second week of March.