Posted on 06/21/2011, 6:44 am, by mySteinbach

Provincial sandbagging machines are in operation in The Pas, at the Brandon Correctional Centre, Kapyong Barracks, in Crane River and in the RM of Ste. Rose.

An additional 23 people were evacuated from the Lake Manitoba First Nation due to rising levels on Lake Manitoba on June 18 and 19. In total, there are 202 people evacuated from the community.

The Canadian Red Cross has registered an additional 12 people evacuated from the RM of Siglunes as a precautionary measure. Some residents may be staying with friends or family, and have not yet registered with the Red Cross. In total, 73 people are evacuated.

A total of 44 people are evacuated from the RM of Alonsa. The Red Cross registered an additional eight people on June 18.

The number of evacuees registered with the Canadian Red Cross and the Manitoba Association of Native Fire Fighters who are currently evacuated is 2,590. This number does not include people who have self-evacuated and not registered.

Flood Forecast Summary

For June to date, Weyburn, Sask., has received 157 millimetres of rainfall which translates to 215 per cent of normal precipitation for June. As well, Estevan, Sask., has received 227 mm of rainfall this month, translating to 300 per cent of normal precipitation for June. A map can be found at www.manitoba.ca/flooding.

There is an unstable weather system developing today and tomorrow generally bringing up to 10 mm of rain over southern Alberta and southwest Saskatchewan, up to 30 mm of localized rain in central and northern Alberta as well as central Saskatchewan, up to 75 mm in localized rain in southeast Saskatchewan and up to 50 mm of rain in the Souris River Basin in North Dakota.

Wind set-up was expected to be light to moderate for all reported lakes today.

Water levels on the Saskatchewan River at The Pas increased 0.08 feet (ft.) since yesterday to 854.54 ft., with a flow of 66,800 cubic feet per second (cfs). In response to recent rainfall in Saskatchewan, reservoirs along the Saskatchewan River are nearing capacity which may cause the Saskatchewan Watershed Authority to increase the outflow from Tobin Lake. The preliminary forecast for Tobin Lake outflow is in the range of 105,000 to 125,000 cfs, which will be reduced by the time it reaches The Pas due to attenuation in the Cumberland Marsh area. This flow is still within the prior forecast levels of 855.5 to 857 ft. in late June. Manitoba Water Stewardship is working closely with the Saskatchewan Watershed Authority to continually update the forecast flows. Local and provincial staff have been preparing the Saskatchewan River dikes in the Ralls Island area in anticipation of increased flows.

The estimated outflow from the Fairford River water control structure is 20,300 cfs today. The structure continues to operate at full capacity due to the high level of Lake Manitoba.

Lake levels at Oak and Plum Lake are high and continue to contribute relatively high flows to Plum Creek.

A high water advisory is in effect for all major lakes in Manitoba.

Assiniboine River

The forecast for the Assiniboine River is based on rainfall received over the past few days and rainfall in the current forecast and indicates:

• Water levels at Miniota are forecast to be sustained at the current level for an extended period of time due to increased inflows from the Qu’Appelle River in response to the recent rainfall event in Saskatchewan.

• Water levels at Virden, Griswold and Brandon are forecast to be sustained at the current level until June 22, then begin a gradual decline.

• Flows at the Portage la Prairie Reservoir reached an instantaneous peak on June 18 at 49,000 cfs. Flows are forecast to continue to decline over the next few days to be below 45,000 cfs tomorrow, then begin flattening out. The anticipated July crest on the Souris River will likely maintain slow recession flows at Portage la Prairie Reservoir during most of July, based on normal July rainfall.

The flood watch for the Qu’Appelle River in the St-Lazare area remains in effect. Water levels on the Qu’Appellle River have decreased by 0.2 ft. since yesterday at 16.35 ft., with a flow of 5,120 cfs. The heavy rainfall received in the upper Qu’Appelle in Saskatchewan will slow the recession at Welby by approximately 10 days from now.

Water levels on the Shellmouth Reservoir are 1,407.21 ft., decreasing 0.09 ft. since yesterday. Inflow into the Shellmouth Reservoir was 2,580 cfs and outflow was 3,270 cfs today.

Flow at Holland on the Assiniboine River was down to 42,800 cfs this morning. The recession will become more gradual, but is forecast to continue based on the current rainfall forecast.

Inflow upstream of Portage la Prairie was 46,790 cfs. Flows in the Portage Diversion channel are 28,760 cfs. Flows on the Assiniboine River at the Portage Reservoir control gates are 18,030 cfs.

Water levels in the Baie St. Paul area are 799.99 ft., decreasing 0.05 ft. since yesterday.

The flood warning for the Assiniboine River at all points downstream of the Shellmouth Dam remains in effect.

Souris River

In response to recent rainfall in Saskatchewan, the outflows from the Rafferty and Alameda reservoirs were increased, which will affect flows on the Souris River.

The Rafferty Reservoir is currently 2.54 centimetres above the maximum allowable flood level with an outflow of 14,832 cfs. Portions of the basin received 30 to 60 mm of rain yesterday, with a further 50 to 60 mm forecast for today. The Saskatchewan Water Authority opened the gates fully as there were concerns the additional inflow from yesterday’s rainfall might exceed the spillway capacity of 20,483 cfs.

Outflows of the Alameda and Boundary reservoirs may also have to increase in response to recent rainfall over Saskatchewan, although not to the extent of the Rafferty Reservoir. It is expected the Boundary Reservoir will exceed its prior peak.

The combined Rafferty, Alameda, and Boundary reservoir flow is forecast to result in a crest near 18,000 cfs at Sherwood, N.D.

Forecasts for the Souris River Basin in Manitoba will be updated once the U.S. National Weather Service forecast for points from Minot, N.D., through Westhope, N.D., is revised. The crest is expected to be significantly attenuated by Lake Darling and the J. Clarke Salyer Wildlife Refuge, as well as the over-bank storage, but high flows will be sustained within Manitoba. Precipitation during the next three weeks will be very critical.

Water levels at Wawanesa are at 1,157.86 ft., decreasing 0.09 ft. since yesterday. The flow at Wawanesa is 17,900 cfs. Water levels at the town of Souris decreased 0.17 ft. since yesterday to 1,358.89 ft. today with flows of 17,000 cfs.

Plum Creek decreased 0.04 ft. since yesterday to 1,375.3 ft. A flood warning for all reaches of Pipestone Creek and downstream into the Oak and Plum Lake system, then on Plum Creek to the Souris River including the town of Souris remains in effect.

The flood warning for the Souris River remains in effect.