Canada's renewable water assets each year amount to a volume of water about the size of Lake Huron. These assets are mostly the result of rain and melted snow that flow over the ground, eventually reaching our rivers and lakes.
Between 1971 and 2000, the volume of this water runoff amounted to an annual average of 3 435 cubic kilometres. Lake Huron contains roughly 3 540 cubic kilometres.
This is the first comprehensive estimate of freshwater flow at the national level using a systematic methodology that has been consistently applied across the country.
The quantity of runoff varies across the country. There is less runoff and greater year-to-year variability in the Prairie provinces and in parts of central and south-east British Columbia. Smaller quantities and higher variability point to potential issues between the availability of water resources and the often competing demands for those resources.
Each year the Canadian economy withdraws about 1.4 percent of the country's renewable water resources.
More at
http://www.statcan.gc.ca/daily-quotidien/090618/dq09...