When summer arrives, gardeners will wish they
could have saved some of the rain that ran down their driveways in the
spring. A University of Georgia scientist is studying ways people can
"Outdoor use is a
major component of the total
water demand for urban areas," said Rose Mary Seymour, a UGA
engineer.. "But in times of drought and water restrictions, landscape
will most likely be a low priority for potable water
researcher in the UGA College of
and Environmental Sciences, has found that using rainwater can reduce
amount of drinkable water used for irrigation.
rainwater is of suitable quality to be
used for irrigation if the rain falls on relatively clean, impermeable
areas," she said. "Collecting rainwater in a retention area also helps
remove nutrients and other pollutants and recharges the groundwater."
studies highlight two rainwater
called rain harvesting, collects
in a cistern, tank or pond. The other involves installing a rain garden
or bioretention area in your landscape.
systems most often collect
in a storage tank, either above or below the ground. A pumping system
supply an automated irrigation system, but the water must be filtered.
Or the rainwater can be siphoned from the tank and applied by hand.
Unlike gray water,
or wastewater from clothes
showers, etc., collecting and applying rainwater doesn't require
plumbing codes, Seymour said. It doesn't contain the detergents and
found in gray water.
The catch is that
rain harvesting systems are best
when they're designed and installed in a new building, Seymour said.
retrofit rain harvesting systems are more expensive and may not fit
with the existing overall site design," she said.
Rain-harvesting systems add some costs over using
municipal water alone for irrigation. But Seymour said landscape
need to be forward-thinking.
water costs continue to rise and
water utilities set up conservation fee structures, the payback period
for rainwater harvesting could be shortened," she said.
and bioretention areas are other
both intentional low areas where runoff
water from impervious surfaces is diverted and contained so the runoff
will infiltrate the soil," Seymour said.
are most often used in home or other
small-scale landscapes, she said. Using plants that fare well in wet
dry extremes, these gardens create a more natural flow. They keep
in the landscape, rather than letting it run into streets and storm
"A rain garden
catches the runoff water from a
particular impervious area such as a rooftop, patio, driveway or
area," Seymour said.
shouldn't stand in a rain garden
more than 48 hours after the rain stops. Since it isn't standing water,
mosquito breeding isn't a problem.
Don't install rain
gardens over the drain field
of septic systems or next to building foundations.
Bioretention areas serve a similar function, but
tend to be part of large, commercial landscapes. They collect rainwater
from large roofs and parking lots.
businesses can combine rain harvesting
bioretention areas and rain gardens, Seymour said.
rain garden downstream from the
of a rain harvesting system can be an even better on-site storm-water-
reduction system than either independent method," she said.
which system you choose," she said,
"using rainwater to reduce the use of potable water on landscapes is a
win-win strategy for both commercial and residential