Hudson Bay drainage basin
The Hudson Bay drainage basin is the drainage basin in northern North America where surface water empties into Hudson Bay and adjoining waters. Spanning an area of about , the basin is almost totally in Canada (spanning parts of the Prairies, central and northern Canada), with a small portion in the United States (in Montana, the Dakotas, and Minnesota). The watershed's headwaters are in part on the Continental Divide of the Americas, and the watershed's connection to the Labrador Sea is at the Hudson Strait's mouth between Resolution Island in the Qikiqtaaluk Region and Cape Chidley on the Labrador Peninsula. On the Continental Divide the basin is bounded at Triple Divide Peak to the south, and Snow Dome to the north.
Drainage basin
A drainage basin is any area of land where precipitation collects and drains off into a common outlet, such as into a river, bay, or other body of water. The drainage basin includes all the surface water from rain runoff, snowmelt, and nearby streams that run downslope towards the shared outlet, as well as the groundwater underneath the earth's surface. Drainage basins connect into other drainage basins at lower elevations in a hierarchical pattern, with smaller sub-drainage basins, which in turn drain into another common outlet.