A “controlled spill” from the surging Assiniboine River is now set for sometime Saturday, Emergency Measures Minister Steve Ashton said at Thursday’s flood briefing in Winnipeg.
A time had yet to be announced.
Meanwhile, the goal is still protect the 150 or so homes in the flood zone before the water arrives, he said.
“I can’t say it enough times,” Ashton said. “We are not giving up on any of the homes in that area. We’re going to do absolutely everything we can with every system we have available to us to try and make a difference.”
Ashton added protecting all the homes will be a challenge, but one made easier because of the army’s help — there are more than 1,000 troops fighting the flood — as well as the delay in activating the controlled release structure at Hoop and Holler Bend on PR 331, southeast of Portage la Prairie.
While postponing the controlled spill has caused anxiety for people in the flood plain, Ashton said it has also provided more time to protect homes.
The 14 homes immediately downstream from the structure have been protected and evacuated, said Chuck Sanderson, executive director of the Manitoba Emergency Measures Organization. A rapid deployment team is working to protect 39 other houses nearby.
Further downstream flood protection will be done by a combination of homeowners and volunteers and where needed, municipal and provincial workers and the army, he said.
It’s expected electricity — crucial for powering pumps — will continue to be available in the flood zone, Sanderson said.
When the controlled spill occurs Saturday it will start at just 500 cubic feet per second (cfs) and over a few days be raised to 3,000 cfs, said Steve Topping, Manitoba Water Stewardship’s executive director of regulatory and operational services.
The La Salle River can handle about 4,000 cfs before spilling its banks. The water from the controlled spill will slow as it travels downstream and ponds in certain areas.
Homes in the communities of Starbuck, Sanford and La Salle should be safe, but those living along the La Salle are being advised to beef up their flood protection, Sanderson said.
“This is not a matter of trading off one area against another,” Ashton stressed.
The controlled spill area would is the same area that would be affected by an uncontrolled breach of the dikes along the Assiniboine, except more land and homes would be affected, he said.
The good news is capacity of the Portage diversion, thanks in part to modifications, has been boosted to 32,000 cfs and it might go up to 34,000, versus the 25,000 cfs it was designed to handle, Ashton said.
However, with even more water coming the dikes are vulnerable due to pressure they weren’t engineered to handle so a controlled spill is necessary.
Once the flood is over the Manitoba government will work quickly to assist in draining the land so farmers can get seeding as quickly as possible, Topping said.
— Allan Dawson is a reporter with the Manitoba Co-operator at Miami, Man.