McKay Lake is a lake

Lake

A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

 in Lake Superior

Lake Superior

Lake Superior is the largest of the five traditionally-demarcated Great Lakes of North America. It is bounded to the north by the Canadian province of Ontario and the U.S. state of Minnesota, and to the south by the U.S. states of Wisconsin and Michigan. It is the largest freshwater lake in the...

 drainage basin

Drainage basin

A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

 in the east part of Thunder Bay District

Thunder Bay District

Thunder Bay District is a district and census division in Northwestern Ontario in the Canadian province of Ontario. The district seat is Thunder Bay....

 in northwestern

Northwestern Ontario

Northwestern Ontario is the region within the Canadian province of Ontario which lies north and west of Lake Superior, and west of Hudson Bay and James Bay. It includes most of subarctic Ontario. Its western boundary is the Canadian province of Manitoba, which disputed Ontario's claim to the...

 Ontario

Ontario

Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....

, Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 and the source of the Pic River

Pic River

The Pic River is a river in the east part of Thunder Bay District in northwestern Ontario, Canada. It flows from McKay Lake southeast of the community of Longlac and empties into Lake Superior southeast of the town of Marathon.-Course:...

. The northeast tip of the lake is 2 kilometres (1.2 mi) southwest of the Canadian National Railway

Canadian National Railway

The Canadian National Railway Company is a Canadian Class I railway headquartered in Montreal, Quebec. CN's slogan is "North America's Railroad"....

 mainline, 15 kilometres (9 mi) south of Ontario Highway 11 and 17 kilometres (11 mi) west of the community of Caramat.

The lake is 19 kilometres (12 mi) long and 6 kilometres (4 mi) wide and lies at an elevation of 321 metres (1,053 ft). The primary inflows are (counterclockwise

Clockwise

Circular motion can occur in two possible directions. A clockwise motion is one that proceeds in the same direction as a clock's hands: from the top to the right, then down and then to the left, and back to the top...

from the Pic River outflow): the Pout River at the southeast; an unnamed creek from Little McKay Lake at Yankee Bay at the north; and Sandlink Creek at Northeast Bay at the northeast. The primary outflow is the Pic River at Outlet Bay at the southeast tip of the lake, controlled by the McKay Lake Dam.

Big Island in the centre of the lake is surrounded by the North, Morrin, South and West Channels. Other named bays include Boot Bay and Portage Bay at the southwest and Reedy Bay at the east.