Environmental Engineering Reference
In-Depth Information
all the water gets absorbed. If you develop it with roads, houses,
driveways, and sidewalks, you can't add anything to the runoff.”
That means all the rainwater from the downspouts, off the roofs,
and running on the pavement has to be stored and cleaned—in the
case of some pollutants, removed—before it goes back into the gutters
as runoff. That's a tall but doable order, helped by several techniques
including using sand, trees, and grassy areas as fi lters, says Austin.
Downspouts aren't connected directly into storm drain systems, either.
Instead, they come down to the bottom of a house and in general
pour onto gravel, rock, and natural grasses—not turf—that naturally
slow down the water fl ow and cleanse the water. Another drain system
then may dump the water into a large planter strip between the curb
of the street and the sidewalk. The native grasses in the planter absorb
much of the water, cleanse it, and then allow it to fl ow through to the
lowest point in a subdivision, where the cleansed and slowed-down
water then fl ows into the drainage system.
Such environmental awareness comes at a price, however, because
it requires more space, which means less room to build homes. “The
Water Quality Control Board has legal status in our state and can
fi ne or arrest people if they're violating water quality laws,” says Austin.
“You can't get a subdivision here approved unless you are meeting the
requirements of [the] laws, so everybody is on an equal playing fi eld.
Every builder has to do it. They know everybody else is spending the
money or devoting the land to do it, so they all do it.”
Implementing that kind of legal requirement is the way to get
water-conscious construction techniques implemented elsewhere in
the country, adds Austin. “It's not going to be popular. But it can be
done, and it has to be done. This can be done city by city, but it's
far more effective on a state or regional basis.”
YET ANOTHER BLUEPRINT
The Subcommittee on Water Availability and Quality of the
National Science and Technology Council's Committee on
Environment and Natural Resources in 2007 proposed a strategy to
