Environmental Engineering Reference
In-Depth Information
(American Planning Association), and author of
Sustainable Design:
Ecology, Architecture, and Planning
( John Wiley & Sons, 2007). As
an architect and urban and regional planner, Williams has stud-
ied water and planning issues in Hawaii, Washington, Florida,
Colorado, Arizona, New York, Louisiana, and points in between.
For example, he says, “Colorado sells its water to Arizona, which
is basically one desert selling it to the other. The aquifer that serves
Tucson, Arizona, is down three hundred feet from water levels one
hundred years ago. We're irrigating desert for our food source,
because we've built all over the best arable land. A large percent-
age of our breadbasket right now is irrigated with million-year-
old [ancient aquifer] water and water from Canada through the
Columbia River and some of the other large transcontinental rivers.
No city in the country supplies its own water within its geopolitical
boundaries. So it's literally
stealing
water from another place, which
isn't a problem as long as that other place doesn't need it. But once
they need it, there's a big problem.
“It's a disaster waiting to happen,” adds Williams, who currently
is working on a topic on urban design with climate change in mind.
“No one thinks the United States has a water problem,” says Mike
Hightower, water expert, environmental engineer, and Distinguished
Member of the Technical Staff, Sandia National Laboratories. Based
in Albuquerque, New Mexico, Sandia is part of the U.S. government's
National Nuclear Security Administration, which studies water as
a national security issue. “We have developed an extensive network of
dams over the last hundred years, which has helped harness our vast
fresh surface water resources. But we haven't built any major dams in
the last twenty-fi ve years, and we've maximized the use of our avail-
able surface water resources. To meet the growing demand for fresh-
water over the past several decades, we've gone to major utilization
of groundwater in our aquifers [underground water supplies], and
we've begun to overpump those.”
A consequence of overpumping water from many of the aquifers
that have been drawn down is that the water left over is often brackish
or salty. Saltwater is heavier than freshwater and generally settles closer
to the bottom of an aquifer, says Hightower. States that have had to deal
with overpumping and salinity issues in parts of their aquifers include
Arizona, North Dakota, Nebraska, California, Minnesota, Ohio, Illinois,
