The province is preparing to close the cut at Hoop and Holler bend to limit the number of properties deliberately flooded.
The timing of the closure, perhaps as early as this weekend, depends on how soon the flood crest on the Assiniboine River moves through the Portage la Prairie area and how well dikes along the river are holding.
The crest passed through Brandon Monday and the Holland area Tuesday and is expected to arrive at the Portage Diversion early today.
"If we can confirm that it's peaked and the water starts declining, then obviously we can start winding back some of these special measures," Premier Greg Selinger said as he explained the plans now underway for Hoop and Holler Bend.
Since Saturday, when the province dug a channel in Provincial Road 331 to spill water out of the swollen Assiniboine River, only three homes have been surrounded by the resulting flow and about three kilometres of land have been covered with water. Up to 150 homes in the Newton and Oakville area have been sandbagged.
Selinger said the timing of closing the PR 331 breach depends on how well the Portage Diversion handles the cresting of the Assiniboine. If all goes well, most sandbagged homes will stay dry.
"The water has been guided in a way that it has not impacted a lot of these homes," Selinger said. "If we can get as few of these homes or properties affected, then I think it's all to the good."
The release from the dike breach has been maintained at 400 cubic feet per second, with the outflow steered towards the Elm River, which connects with the La Salle River, which empties into the Red River.
The province had originally forecast it would release up to 3,000 cfs through the PR 331 breach.
Warmer weather has helped the flood fighters, enabling Canadian Forces personnel, 1,700 of whom are now in the flood zone, and provincial workers to shore up 17 identified weak spots in dikes along the Assiniboine.
"The good news in the last few days is that we're now seeing far less water levels than we had feared initially," Emergency Measures Minister Steve Ashton said Tuesday of the intentional flooding through the PR 331 breach.
Steve Topping, the province's flood-fighting chief, said closing the Hoop and Holler controlled release depends on how well the Portage Diversion, which funnels water from the Assiniboine into Lake Manitoba, handles the forecast crest of 52,000 cfs into the Portage Reservoir.
"We need to be very careful with the integrity of the system," Topping said. "(The diversion) is expected to run much longer at well above its designed capacity. The controlled release is needed in case of a problem with the capacity of the Portage Diversion, in case there is some failure of a structure."
Ashton said a preliminary estimate of damage from this year's flood is about $200 million. In the 1997 Red River Valley flood, the damage was $280 million.
Selinger said the province is in the final stages of putting together a compensation package for people affected by this spring's floods.
"I think that the challenge here is to come with a program that's fair," he said. "It will be a program that goes beyond the normal disaster financial assistance support in Manitoba."
He said the province plans to relax the assistance programs to include homeowners, farmers and businesses.
"There is a deductible, and we think it might not be appropriate in these circumstances," he said. "We think we can get something out late this week or early next week."
The latest stats
Provincial staff will host meetings with rural municipalities and First Nations around Lake Manitoba and Lake St. Martin to deal with unprecedented flooding.
The revised forecast peak for Lake Manitoba is 815.8 feet. The revised forecast for Lake St. Martin was is 805.2 feet.
Lake Manitoba will rise at least two inches by the additional water being pumped out of the Portage Diversion.
As Lake Manitoba expands, so does Lake St. Martin to the north. Lake St. Martin empties into Lake Winnipeg via the Dauphin River.
In Brandon, First Street opened to northbound traffic Tuesday.
There are 113 provincial roads affected by water, and there are 663 municipal roads closed.