The Worlds Water Supply
Water is one of the Earth's most abundant natural resources, but
the total amount of water available is fixed. Earth has the same
amount of water today as it did when life first emerged on the
That's because our water is in a continuous process of use
and reuse. In fact, the water we drink today was the same water the
dinosaurs drank. You could actually be sharing a drink with Julius
Caesar, Cleopatra or even George Washington!
Most of the world's water supply is in the form of salt water
stored in the oceans. Since converting salt water to fresh water
for drinking is generally expensive, it is rare to find a city that
relies on salt water as its water source.
Only three percent of the world's water supply is fresh water, and
two-thirds of that water is frozen, in the form of polar ice caps,
glaciers and icebergs. Thus, only one percent of the overall supply
is fresh water that can be found as either surface or groundwater
and used for human consumption.
You'll find surface water in lakes, rivers, ponds and streams,
while groundwater is underneath your feet in underground aquifiers.
Groundwater systems are more numerous, but serve smaller
populations, while surface water systems serve larger groups.
Others receive their water supply from private wells that also tap
As the world's population continues to increase, so does the demand
for water; however, the world's water supply does not increase.
What there is, is unevenly distributed through precipitation
because of varying conditions such as climate and water consumption
by plants and animals.
So there is not always enough water in places where it is needed.
And due to growing populations and industry, the total amount of
clean water available is constantly diminishing.
Those of us who reside in developed countries should count
ourselves among the fortunate, in terms of water supply. Relatively
clean water is a constant in our lives, readily available whenever
we need it.
However, even developed countries suffer from water woes and
contamination issues related to aging infrastructure,
treatment breakdowns, human error and geological influences.
In underdeveloped countries, the water crisis tops the list of
issues to be addressed. More than 1.5 billion people around the
world lack a safe and reliable supply of drinking water, and
water-related diseases are the leading cause of deaths across the