Canada: Water surplus will emerge in Gatineau River Watershed

28 April 2020

THE BIG PICTURE
The 12-month outlook for Canada through December indicates a forecast of deficits for much of Quebec north of the Gouin Reservoir in the Mauricie region of the province including vast areas of exceptional deficit.

Canada_Composite_Adjusted_202001-202012_12mo_twitter.png

Exceptional deficits are forecast for western Labrador, a column along Ontario’s northeastern border, the southwest corner of Hudson Bay, a belt across central Manitoba north of Lake Winnipeg reaching into Ontario, central Alberta west of Edmonton and in the province’s northwest corner.

A large block of extreme to exceptional surplus is forecast surrounding Churchill Lake in northern Saskatchewan leading north well past Lake Athabasca and west past Fort McMurray, Alberta. Moderate to extreme surpluses are expected around Fort St. John in northern British Columbia, and intense surpluses in the southern Columbia Mountains.

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

The forecast through June for Canada’s most populated areas indicates nearly normal water conditions for Québec City, Montreal, Ottawa, Saskatoon, and Edmonton; surpluses near Toronto and Calgary; and deficits around Winnipeg and Regina and on Vancouver Island.

Canada_Composite_Adjusted_202001-202012_3mo_twitter.png

Deficits will shrink in northern Quebec (QC) though vast pockets will persist in the east, and also west of Lake Mistassini. Surpluses will emerge in the Gatineau River Watershed north of Ottawa and at the mouth of the St. Lawrence River. Intense deficits are forecast in a wide path along Ontario’s (ON) northeastern border; moderate to extreme deficits in pockets of Southern Ontario with surpluses near Toronto; and severe to exceptional deficits in the province’s northwest quadrant. Surpluses in Northern Ontario will shrink considerably.

In the Prairie Provinces, exceptional deficits are forecast in a wide band north of Lake Winnipeg, Manitoba (MB) and in the northeast along Hudson Bay; a small pocket of extreme deficit is expected around Winnipeg. In Saskatchewan (SK), moderate to severe deficits are expected around Regina, and exceptional deficits in the Upper Assiniboine River region. Intense surpluses will persist in a vast block of northwestern SK reaching across the border past Fort McMurray, Alberta (AB).

Exceptional deficits will persist in northwestern AB and the Middle Reaches of the Athabasca River Watershed in the center of the province. Surpluses will increase along the South Saskatchewan River and along the central border of AB and British Columbia (BC) in the Peace River region, reaching Fort St. John, BC. Surpluses will increase in southeastern BC and deficits will increase on Vancouver Island.

From July through September, deficits will increase in eastern Canada, covering much of QC and Labrador, though conditions in southern QC will normalize. Deficits will increase in ON, persisting in Southern QC and increasing in Northern QC. Surpluses will persist near Toronto. The forecast for the northern regions of the Prairie Provinces will be much the same as in the prior three months while anomalies will generally diminish in the south. Surpluses will persist in much of southern BC but transitional conditions are also forecast in the southeast, and deficits will intensify somewhat in southern Vancouver Island, moderating in the north.

The forecast for the final three months – October through December – indicates that deficits will shrink overall, particularly in QC as normal conditions return to much of the province. Southern Ontario will return to normal as well and near-normal conditions are expected in the southern regions of the Prairie Provinces.

(It should be noted that forecast skill declines with longer lead times.)

IMPACTS
Flooding in British Columbia’s Central Interior has prompted an evacuation order in the community of Williams Lake near the Fraser River, with the city’s emergency director describing conditions as “100 to 200 year flows going through the river valley.” Officials in the region, known as the Cariboo, are concerned that the flooding could overwhelm the Williams Lake sewage system, pushing raw sewage into the Fraser River.

Snowpack has been high in several BC regions, adding to flood concerns, particularly if May brings warm weather and significant precipitation. As of early April, three regions were classified as having “extremely high” snowpack, 135 percent of normal: Upper Fraser East, Upper Fraser West, and the Cariboo Mountains. Several other regions had “high” snowpack, 120 percent of normal.

Late April ice jams on the Athabasca and Clearwater RIvers caused widespread flooding in downtown Fort McMurray in Alberta Province, forcing thousands to evacuate.

Wildfire season in Alberta began March 1, a month earlier than any other province. The provincial government instituted a fire ban effective April 15 on 60 percent of the province and will hire an additional 200 firefighters at a cost of $5 million (US $3.6 million). Up to $20 million (US $14.3 million) more will be earmarked for fire prevention programs. Since March 1, the province has recorded 20 wildfires in its Forecast Protection Area, the area under the current fire ban.

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