Environmental Engineering Reference
In-Depth Information
“In a natural system, water is captured, stored, and released,
which provides both fl ood mitigation and water supply needs. In
an urban system, the traditional challenge has been one of getting
the water out of the neighborhood as soon as possible—typically
sending it underground or shunting it to the ocean or bay,” says
Williams. “Now that water has become the limit to growth and
development, the challenge is how to store the water within the
urban and regional pattern so that communities utilize the water
that lands there.”
Williams suggests that urban areas that historically fl ood could
be designed with small parks that pond or store water, “creating
a pattern of open spaces and neighborhood gardens paid for by
storm water dollars—a win-win.”
“We need to connect design and science—then you have real
solutions integrated into the urban fabric,” he adds.
Down the Drain—Literally
Remember the Boston metropolitan area's loss of potable water
through sewer pipes? It's not just leaky pipes that collect and lose
good water. “Add the impact of paved and impervious surfaces
in metropolitan areas, urban centers, suburbs, and exurbs in that
same forty-three-town metropolitan area, and in a dry year add
another 50 billion gallons of water that goes into storm drains and
is instantly lost rather than infi ltrating back into the ground,” says
Zimmerman of the Charles River Watershed Association. “In a wet
year, it's as much as 120 billion gallons. Added to the potable water
losses in sewer pipes for those same forty-three towns, we're throw-
ing away the equivalent of two Charles Rivers in their entirety every
single year!”
Zimmerman bases his numbers on his organization's analysis
as well as data from the 2002 study by American Rivers, the Natural
Resources Defense Council, and Smart Growth America titled
“Paving Our Way to Water Shortages: How Sprawl Aggravates the
Effects of Drought
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“With the exception of the semi-arid and arid Southwest, the
notion that somehow urban America is running out of water is ridic-
ulous,” says Zimmerman. “Instead, we're throwing our water wealth
