Province of Manitoba | Archived News Releases

July 4, 2011

Flood Bulletin #89

Approximately 375 Canadian military forces personnel from CFB Shilo and volunteers are expected to complete sandbagging efforts in the town of Souris tomorrow. The Souris River flood forecast improved somewhat yesterday based on new flow numbers from the National Weather Service (NWS) in the U.S. The river will still experience record flows, but the lower forecast provides for more freeboard on the dikes. Work to reinforce and build dikes and other flood-protection systems in Melita, Hartney and Wawanesa is complete. The Souris River crested in Melita yesterday.
In The Pas, there are approximately 60 pieces of equipment still working to raise and build dikes beyond a one-in-100-year flood level along the Saskatchewan River. Sandbagging is also continuing along the Carrot River.
There are currently 2,944 Manitobans evacuated from their homes.

Flood Forecast Summary

An unstable weather system is developing today and tomorrow over most of Saskatchewan and Manitoba, and the U.S. portion of the Red River basin in North Dakota. All areas are expected to receive up to five millimetres of rain by Tuesday evening, with localized cells bringing up to 40 mm over northern Saskatchewan, northern Manitoba and an area from over the north basin of Lake Winnipegosis to Lake Winnipeg.

Souris River

In the U.S., Westhope, N.D., peaked on July 3 at 25,100 cubic feet per second (cfs), which is a lower flow than previously forecast by the U.S. NWS. The Souris River forecast for Manitoba has been revised to reflect this reduction as well as the current favourable weather conditions that are forecast to continue in the short term.
The Souris River forecast, taking into consideration the current NWS Westhope forecast, and weather and flow conditions within Manitoba, is shown in the table below.

The Plum Creek at Souris decreased 0.01 ft. since yesterday to 1,373.5 ft. A flood warning for all reaches of Pipestone Creek and downstream into the Oak and Plum Lake system, and on Plum Creek to the Souris River including the town of Souris remains in effect.

Assiniboine River

Inflow upstream of Portage la Prairie is expected to start rising later today in response to the large flows from the Souris River basin. The inflow into Portage la Prairie is forecast to reach 44,000 to 45,000 cfs between July 8 and 14.
The Shellmouth Reservoir will be operated today to increase the conduit outflow by 600 cfs.

Red River

Water levels on the Red River at James Avenue in Winnipeg have increased by 0.08 ft. since yesterday to 17.38 ft. Flows at James Avenue this morning were approximately 49,600 cfs. A crest occurred on June 28 in Winnipeg due to high local tributary flows. The Red River is still rising due to increased flow from upstream with some local inflow still contributing, but will stay within its banks.

Lakes

The provincial wind set-up alerts forecast for today include:
- A moderate wind set-up alert for the east, west and south shores of Lake Manitoba, the east shore of Oak Lake and the South Basin of Lake Winnipeg. This includes communities such as Steep Rock, Vogar, Lundar Beach, St. Laurent, Twin Lakes Beach, Westbourne, Sandy Bay, the Ebb and Flow First Nation, Crane River, Meadow Portage, Homebrook, Oak Lake Beach, Gimli, Chalet Beach, Victoria Beach, Traverse Bay and O’Hanly.
The provincial wind set-up alerts forecast for tomorrow include:
- A moderate wind set-up alert tomorrow for the south basin of Lake Manitoba and Lake Winnipeg, and the south shore of Lake Winnipegosis. This includes communities such as Sandy Bay, Westbourne, Twin Lakes Beach, St. Laurent, Lundar Beach, Gimli, Chalet Beach, Victoria Beach, Traverse Bay, O’Hanly and Winnipegosis.
The estimated outflow from the Fairford River water control structure is 20,700 cfs today. The structure continues to operate at full capacity due to the high level of Lake Manitoba.
The water level on Rock Lake is 1,335.19 ft. The June 30 level on Pelican Lake was 1,353.2 ft., which is below the spring peak level. The outlet at Pelican Lake is operating at full capacity, with all three gates fully open.

Saskatchewan and Carrot Rivers

Water levels on the Saskatchewan River at The Pas increased 0.1 ft. since yesterday to
856.44 ft., with a flow of 78,000 cfs. The forecast range for The Pas remains at 858 to 859.3 ft. with the peak occurring between July 7 and 12. The water levels are forecast to steadily rise from current levels to reach the forecast peak. The water level stage of 859.3 ft. corresponds to the 100-year flood event for the Saskatchewan River at The Pas.
The forecast peak water levels on the Carrot River will be affected by the peak water level on the Saskatchewan River, from the downstream end of the Carrot River to about mile 18. The forecast peak water levels in that portion of the Carrot River are 859.9 to 861.2 ft., expected to occur between July 7 and 11. Upstream of mile 18, the forecast peak is expected to be somewhat below the spring peak in April.

For more information, see www.manitoba.ca/flooding. The most up-to-date highway information is at www.gov.mb.ca/mit/roadinfo or 1-877-MBRoads (1-877-627-6237) and on Twitter by following @MBGov.

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Après la publication de chaque rapport sur les inondations, les renseignements sont mis à jour en français dès que possible.