Alberta thus gives rise to the two great rivers Saskatchewan and Mackenzie.
With the organization of Manitoba and the opening of improved communication immigrants began to move rapidly westward, and government surveyors were soon busy laying off lands in the Saskatchewan valley.
The precipitation in southern Saskatchewan and Alberta is much more variable than farther east and north, so that in some seasons crops have been a failure through drought, but large areas are now being brought under irrigation to avoid such losses.
All of these are rapid and shallow, affording navigation only for canoes; but the largest of them, Nelson river, drains the great Manitoban lakes, Winnipeg, Winnipegosis and Manitoba, which are frequented by steamers, and receive the waters of Lake-of-the-Woods, Lake Seul and many others emptying into Winnipeg river from Ontario; of Red river coming in from the United States to the south; and of the southern parts of the Rocky Mountains and the western prairie provinces drained by the great Saskatchewan river.
This great plain runs north-westward between the border of the Archean protaxis and the line of the Rocky Mountains, including most of Manitoba, the southern part of Saskatchewan and most of Alberta.
The northern part of Alberta and Saskatchewan and much of northern British Columbia are drained through the Athabasca and Peace rivers, first north-eastwards towards Athabasca Lake, then north through Slave river to Great Slave Lake, and finally north-west through Mackenzie river to the Arctic Ocean.
The completion of the St Andrew's Rapids canal on Red River, and the Grand Rapids canal on the Saskatchewan river will again give an impetus to inland navigation on the tributaries of Lake Winnipeg.
By the Canadian provinces of Saskatchewan and Manitoba, S.
Of this total wheat acreage, 2,721,079 acres were in Manitoba, 2,117,484 acres in Saskatchewan, and 223,930 acres in Alberta, with average yields per acre at the rates of 20.02 bushels in Manitoba, 23.70 in Saskatchewan and 26.49 in Alberta.
By way of the North Saskatchewan river Alexander Mackenzie crossed the height of land, and proceeding northward discovered the river which bears his name, and also the Arctic Sea.