The water cycle continuously revitalizes the Earth's
fresh water supplies. This supply has been constant for millions
of years. What changes, is the demand for water by an increasing
world population and the accompanying industrial municipal and
agricultural demands. Currently, the world's water supply is
sufficient to supply four times the Earth's existing population, if it
was available in the right places at the right time. As we all
know however, it is not!
Of all the water in the
world, 97.5% is salt water. The remaining 2.5% is fresh but a
significant amount is tied up in the polar ice caps. This leaves
less than 1% of the world's water supply available to meet the fresh
water demands of all living things. Some parts of the world
experience floods, other parts are drought-ridden.
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Access to good
quality water is not equally shared throughout the globe. Even in
Canada, which has the largest per capita water supply in the world,
water shortages can be experienced. Most Canadians live within 200
kilometres of the Canadian-American border, yet a significant portion of
our water is in the northern regions of Canada. Even in Alberta,
80% of our water supply lies in the north while 80% of the water demand
comes from the southern half of our province. Locally, as well as
globally, disparity in the available water supply is a common theme that
helps drive the need for conserving water. For most of Alberta,
however, there are other reasons to conserve water that are equally
important.
Reprinted from Focus On Water Conservation (1993) with permission of
Alberta Environment.
[Biological
Properties][Chemical
Properties][Physical
Properties]
[Changing Quality][Conservation
Need][How
to Conserve]
[Effects on Organisms][Pollution][Quality][What
Can You Do?]
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