Canada: Water surplus will intensify in N Thompson Rv, BC

27 May 2022

THE BIG PICTURE
The 12-month outlook for Canada through January 2023 indicates widespread water deficits in the eastern half of the nation.

Deficits will be exceptional in many regions including southern Newfoundland, the Miramichi River watershed in east-central New Brunswick, the Smallwood Reservoir region in Labrador, the Manicouagan Reservoir region in Quebec, and a vast area near Lake Mistassini. Deficits will be somewhat less intense in Southern Ontario east of Georgian Bay, while a small pocket of surplus is forecast west of Toronto. Exceptional deficits are expected in a broad column along Ontario’s eastern border reaching James Bay. Deficits will be widespread in Northern Ontario and will include exceptional anomalies in Kenora District.

Widespread exceptional deficits will belt central Manitoba and are also forecast in the province’s northeast reaching Hudson Bay. Some pockets of severe deficit are expected in southern Manitoba, but surpluses are forecast near the U.S. border in the Red River Watershed. Elsewhere in the Prairie Provinces, nearly normal conditions are forecast across southern Saskatchewan. Central Saskatchewan can expect deficits, but widespread surpluses are forecast in the northwest quadrant leading west past Fort McMurray, Alberta. Exceptional deficits are expected in northwestern Alberta, deficits of varying intensity in the Middle Athabasca River region, surpluses north of Banff, mixed conditions in the south.

Surpluses are forecast in the Thompson River Watershed of southern British Columbia leading east into the Columbia Watershed. Deficits are expected at opposite ends of the province’s southern region in Vancouver Island and in East Kootenay. The Upper Fraser and Nechako River Watersheds will see intense deficits as will British Columbia’s central far north from Williston Lake well into Yukon and Northwest Territories.

The 3-month maps (below) show the evolving conditions in more detail.

FORECAST BREAKDOWN
The forecast through July indicates that vast areas of intense deficit will persist from Quebec (QB) into Labrador and surrounding Lake Mistassini and will emerge in the Ungava Peninsula in Quebec’s far north. Deficits will also persist in eastern Newfoundland while surpluses emerge near St. John’s and in the Exploits River Basin. Deficits will continue in east-central New Brunswick and emerge in Nova Scotia. In Southern Ontario, deficits will be moderate in Ottawa but intense east of Georgian Bay and will increase north of Lake Erie as surpluses retreat. A broad column of exceptional deficit will persist along the province’s eastern border. Deficits will continue in much of Northern Ontario though surpluses are forecast on the U.S. border near International Falls and also farther north around Trout Lake in Kenora.

In the southern regions of the Prairie Provinces, near normal conditions are expected in Saskatchewan (SK) and mixed conditions in Manitoba (MB) and Alberta (AB). Intense deficits will persist in central regions of the Prairies and northern MB and AB, while intense surpluses persist from northwestern SK into AB and increase in the Canadian Rockies of southern AB. In southern British Columbia (BC), surpluses will intensify in the North Thompson and Quesnel River Watersheds. Deficits will retreat from Vancouver Island but persist with intensity in the Upper Fraser and Nechako River Watersheds and from Williston Lake in the far north into Yukon and Northwest Territories. Surpluses will emerge in a pocket near Fort St. John.

From August through October, deficits will shrink and downgrade somewhat in eastern Canada as surpluses nearly disappear. Anomalies will persist in the Prairies though deficits will downgrade a bit and surpluses in southern AB will shrink. Anomalies will shrink and downgrade in BC.

The forecast for the final months – November through January – indicates deficits in northern MB, Northern Ontario, and pockets in Quebec and AB. Scattered pockets of surplus are expected in BC with a pocket of deficit in the far north.

Please note that WSIM forecast skill declines with longer lead times.

IMPACTS
Heavy rainfall and snowmelt combined to produce widespread flooding in Manitoba this spring, particularly in the Red River Basin. As of early April, part of the basin has received between 400 and 600 percent of normal precipitation. Floodwaters turned one farm near Winnipeg into an ocean, waves rippling over cropland. Evacuations were ordered in Montcalm south of Winnipeg as floodwaters breached roads.

Several other regions in Manitoba experienced flooding as well. An ice jam on the Fisher River inundated the Peguis First Nation community in the Interlake Region north of Winnipeg with river levels at the highest in 60 years, forcing 1,000 residents to evacuate and damaging roads, bridges, and water infrastructure. In the west-central Manitoba town of Mafeking, erosion from flooding destroyed bridges, isolating some residents and tearing down trees. In the eastern reaches of the province, the Winnipeg River is at record volume with unprecedented flows from Ontario, flooding much of the river’s massive drainage area.

Nearby in Ontario, a flood warning has been extended through 3 June for several townships near Lake of the Woods in Kenora, Ontario.

NOTE ON ADMINISTRATIVE BOUNDARIES
There are numerous regions around the world where country borders are contested. ISciences depicts country boundaries on these maps solely to provide some geographic context. The boundaries are nominal, not legal, descriptions of each entity. The use of these boundaries does not imply any judgement on the legal status of any territory, or any endorsement or acceptance of disputed boundaries on the part of ISciences or our data providers.

Subscribe to our monthly Water Watch List

Search blog categories

Search blog tags