Environmental Engineering Reference
In-Depth Information
Freshwater 3%
Other 0.9%
Rivers 2%
Surface
water
0.3%
Swamps 11%
Groundwater
30.1%
Saline
(oceans)
97%
Lakes 87%
Icecaps and
glaciers 68.7%
Earth's water
Freshwater
Fresh surface
water (liquid)
FIGURE 1.1 Distribution of Earth's Water
Source:
U.S. Geological Survey.
According to a 2003 report from the U.S. General Accounting
Offi ce:
2
Oceans provide 97 percent—salty and undrinkable, and not
usable for irrigation without costly desalination.
Glaciers, polar ice caps, and groundwater contribute 2
percent—generally frozen and inaccessible.
Surface water, including rivers and lakes, supplies 0.3
percent—generally accessible to satisfy freshwater needs that
include energy, agriculture, and industrial and personal use.
The water crisis is global in scope, yet hits each of us person-
ally. Not only do we need water to live, but we require massive
quantities of it to produce energy, power industries, develop com-
munities, and grow food. Even processing water for consumption
requires huge amounts of water to produce the energy necessary
for pumping, conveyance, treatment, and more. If water is in short
supply, the costs of goods and services that rely on it go up, too.
For years, recycling bathtub and dishwasher water into the
garden or onto the yard was the norm in water-short states like
