Weather gives flood-weary province a break

Lake Manitoba should start dropping before the end of the month as the province appears to have rounded the corner on this year's historic flood fight, Emergency Measures Minister Steve Ashton said Friday.

Warm weather and little rain has lowered the flood crest on the Souris River, which means less water being sent up the Portage Diversion into the already flooded Lake Manitoba, he said.

"I said about a week ago we could use a break in the weather," Ashton said. "We've had a break of about a week in three months worth of flooding."

The revised forecast also means the July 15 crest on Lake Manitoba will be about 0.4 feet lower than first anticipated. It will now crest between 817.3 and 817.5 feet above sea level. It was measured at 817.14 ft. on Thursday.

"Is it good news? I don't know if I would say it's really good news," Ashton said. "But for the first time in several months we have a forecast that's coming out which shows rather than an increase in flood levels and a later crest on Lake Manitoba and Lake St. Martin, we're actually seeing potential for an earlier crest and perhaps, a somewhat lower lake level."

What's contributed to the improved forecast -- Ashton said it could change if we get a lot of rain -- is steady hot summer weather.

"One of the key elements on Lake Manitoba and Lake St. Martin is evaporation," Ashton said.

Ashton also said less water is flowing on the Souris River than first forecast. That means less water entering the Assiniboine River, the Portage Diversion and Lake Manitoba.

The province forecasts flows between 41,000 to 42,000 cubic feet per second -- down from the earlier forecast of about 52,000 cfs -- into the Portage Reservoir. The flood crest is moving through the Souris River with all dikes holding.

However, Ashton and Steve Topping, executive director of Manitoba Water Stewardship, said the threat from windstorms is still high on Lake Manitoba. A May 31 storm destroyed some and damaged hundreds of other cottages and homes in the south basin of Lake Manitoba, and prompted the mandatory evacuation of lakeside communities. People won't be allowed home until the lake freezes over.

In the meantime, permanent dikes are being built and the province is in the early stages of helping people in low-lying areas raise their homes or build dikes, much like what was done in the Red River valley following the 1997 flood.

Topping said the province hopes to get Lake Manitoba's level down to about 814.1 feet by Jan. 1 and below 813 feet by spring.

Ashton also said the province continues to explore how it can drain Lake Manitoba more quickly during flood years. Lake Manitoba empties into Lake St. Martin and experts are looking at a diversion from Lake St. Martin to Lake Winnipeg.

"We're really aggressively moving to a decision point," Ashton said.

Water levels have also risen on the Red River because of recent rainstorms in North Dakota. The province re-opened the Red River Floodway this week to keep levels on the Red in Winnipeg at a more manageable level and to reduce the threat of sewer backup and basement flooding.

The Red River level at James Avenue on Friday was 17.64 feet, with a flow of 50,600 cfs,

The cost of this year's flood is expected to hit $550 million and could climb higher depending on the weather. In the past three months the province has used 10 million sandbags -- including three million in the past 10 days along the Souris River. It's also used 50,000 super-sandbags, 25,000 in the past 10 days along the Souris.

bruce.owen@freepress.mb.ca

Republished from the Winnipeg Free Press print edition July 9, 2011 A5