Manitoba Infrastructure and Transportation’s Hydrologic Forecast Centre reports the lake
wind-effect forecast for tomorrow suggests a high to severe wind warning for Lake Manitoba and Lake Winnipeg. The south-southwest winds could increase water levels and result in significant wave action on north and east shorelines of the lake.
Environment Canada has issued a rainfall warning for much of western Manitoba:
A slow-moving, low-pressure system will move into southwest Manitoba this afternoon and will intensify tonight. Precipitation associated with this weather system spread into southwest Manitoba and the extreme southeast corner of Saskatchewan this morning. The system is expected to move into the Parklands area of Manitoba this afternoon and east central Saskatchewan tonight. Rain will intensify tonight and continue Sunday. General rainfall amounts around 50 millimetres are expected. The Dauphin, Minnedosa, Yorkton and Kamsack regions will see 50 to 75 mm of rain. Weather conditions will begin to improve Sunday night.
Heavy downpours can cause flash floods and water pooling on roads. Localized flooding in low-lying areas is possible. Watch for possible washouts near rivers, creeks and culverts.
The storm system yesterday brought significant rainfall to parts of western Manitoba, with Brandon receiving 51 mm, Dauphin 28 mm, Carberry 38 mm and Melita 15 mm. Winnipeg received 11 mm and Gimli received 24 mm.
Rainfall for Saturday and Sunday will be heaviest in western Manitoba, with general rainfall amounts of 50 mm expected and an area west of Roblin could receive up to 75 mm. Further east, by end of day Sunday, Winnipeg is expected to receive 30 to 35 mm, the Interlake is expected to receive 20 to 40 mm, and eastern Manitoba approximately 25 mm.
Warnings and Advisories
Flood warnings continue for:
Assiniboine River, from the Shellmouth Dam to Brandon, due to high flows;
all points along the Winnipeg River System including Nutimik Lake in the Whiteshell Provincial Park;
Lake St. Martin; and
A flood watch is in place for:
Lake Manitoba, and
High water advisories are in place for:
all points along the Red River; and
all points along the Saskatchewan River.
The Red River is rising at all points in Manitoba from Winnipeg upstream. The Red River at James Avenue in downtown Winnipeg is at 16 feet and is forecast to go up to 16.7 ft. in the next week. The river is forecast to stay above 14 ft. until mid-July.
There is the potential the Red River Floodway could be operated under Rule 4, to reduce the risk of basement flooding damages within Winnipeg, depending on weather conditions.
The water level on the Shellmouth Reservoir has increased to 1,410.4 ft. The summer target level is 1,402.5 ft. and the crest of the spillway is at 1,408.5 ft. As the water level has exceeded the spillway crest elevation, flows are occurring over the spillway. Spillway flows will increase or decrease as the reservoir level rises and falls. Inflows to the reservoir are approximately 3,430 cubic feet per second (cfs) today; outflows from the reservoir are approximately 2,650 cfs. Outflows include 1,050 cfs of conduit flow and 1,600 cfs of spillway flow.
The Portage Diversion is not in operation. Flow on the Assiniboine River upstream of the Portage Diversion is 9,450 cfs. The Portage Diversion will be operated if required to maintain 10,500 cfs along the lower Assiniboine River.
Weather conditions in the Assiniboine River basin will determine if and when the Portage Diversion will be operated.
Lake Manitoba is presently at approximately 813.6 ft. and is forecast to peak in early July at approximately 813.6 ft. with normal weather, or at approximately 813.8 ft. if wetter conditions persist. Lake Manitoba is currently approximately 1.8 ft. below unregulated levels (the levels that would have occurred in the absence of all provincial water control infrastructure) because of the high outflows out of the Lake through the Fairford River Water Control Structure. The actual outflows have been higher than what the natural outflows would have been for all of 2014 and also in previous years.
The Fairford River Water Control Structure is being operated for maximum possible discharge and the outflow from Lake Manitoba is approximately 13,270 cfs. The estimated natural outflow from Lake Manitoba at the current lake level, if the Fairford River Water Control Structure and associated channel improvements hadn’t been constructed, is approximately 4,500 cfs.
The Lake St. Martin gauge is registering a water level reading of 803.1 ft. The wind-eliminated lake level is forecast to peak just above 803 ft.
Work to re-open the Lake St. Martin Emergency Outlet Channel will begin July 2. Operation of the Lake St. Martin Emergency Channel will increase outflow from Lake St. Martin, directly lowering levels and allow the Fairford River Water Control Structure to remain at maximum discharge longer, thus allowing for higher outflows from Lake Manitoba later in the year. The channel is expected to stay open until the spring of 2015 and will help bring the Lake St. Martin water level below 801 ft. by Oct. 31.
Lake Winnipeg is at 715.4 ft. and Manitoba Hydro forecasts that it will rise to approximately
716.1 ft. by late July. The water level regulation range for Lake Winnipeg is between 711 and
715 ft. Manitoba Hydro is operating its structures at the outlet of Lake Winnipeg to allow for maximum possible outflow from the lake.
Dauphin Lake is at 858.5 ft. and is forecast to peak at 859.3 to 859.6 ft. by mid-July. The flood stage on the lake is 858 ft. and the summer target level is 855 ft.
Nutimik Lake, which is part of the Winnipeg River system, is at 908.3 ft., a record high level on the lake. Dorothy and Eleanor lakes, which are downstream from Nutimik Lake, are also experiencing high water levels and some overland flooding. There are reports of boathouses being flooded and some sandbagging is underway. The Lake of the Woods Control Board has indicated that Nutimik Lake could rise by an additional foot by mid-July, depending on weather conditions.
Some roads may be affected, limiting access to cottages in the area. In addition, there are reports of boathouses being flooded and some sandbagging is underway.
Sandbags are available for cottagers at strategic locations.
Cottagers can call the Seven Sisters District Office at 204-348-4004 for more information.
If possible, cottagers are asked to consider pumping out septic tanks that may be affected by overland flooding and refilling them half full with water to prevent them from overflowing or being damaged.
Boaters are encouraged to be cautious as high water levels can lead to more debris in area lakes and rivers.
The Pas and Northern Manitoba
The flow on the Saskatchewan River at The Pas is at 60,990 cfs. Saskatchewan River flows at The Pas are forecast to peak on July 10 at 63,000 cfs, which is approximately 10,000 cfs lower than the open water crest this past spring.
Cormorant Lake is at 844.5 ft. and is forecast to rise by another 0.5 ft. due to the forecast rainfall. Wind setup and wave action on the lake is forecast from 0.3 to 1.5 ft., depending on wind speed and direction.
States of local emergency continue in the rural municipalities of Arthur, Edward and Wallace.
The province will deploy flood mitigation equipment, such as Tiger Tubes, to areas that may be most affected by flooding.
Flood-affected Provincial Parks
Provincial park campgrounds with sites affected by flooding include Birch Point, Watchorn,
St. Malo, Rainbow Beach, Camp Morton, Falcon Beach Campground and Falcon Lakeshore Campground.
All campers with reservations for affected sites have been contacted directly.