Six years ago, Richard McKown decided to build an affordable housing
community of half conventional homes and half homes with green
infrastructure to see which performed better.
It would have been a radical idea in any place, but it was practically
unheard of where McKown worked: Norman, OK, a place with clay soils,
extreme weather and so little in the way of green infrastructure that
the city officials weren’t even using that term. Everything that was not
a traditional curb-and-gutter simply fell into the category of “best
management practices.”
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| Brandon Holzbauer-Schweitzer stands by his stream gauge. The water
eventually goes into the lake that provides drinking water to the
region. (Rona Kobell) |
Today, Trailwoods, the community he built, stands as a monument to
innovation and cooperation. It includes 17 lots that were developed with
conventional stormwater management practices, sitting across a
stormwater basin from 17 homes designed with porous concrete, rain
gardens, rain barrels and downspouts that divert and capture rainwater.
The neighborhood doesn’t just look different, with one side a typical
bare suburbia and the other lush with native plants so high they cover
some of the mailboxes. It is also an experiment. It is one of the few
developments that clearly demonstrates the value of green infrastructure
to control stormwater from small lots.
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Developer
Richard McKown shows a group where his Trailwoods home development is
within the watershed. Half the neighborhood was built with green
techniques, and half with traditional storm water management. (Rona
Kobell)
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A $500,000 EPA monitoring grant to the University of Oklahoma, located
in Norman, has documented impressive water quality results from the
green side: a 30 percent reduction in nitrogen, a 32 percent reduction
in suspended sediment and a 152 percent reduction in phosphorus compared
with the conventional side. All of those eliminated pollutants would
otherwise be flowing into Lake Thunderbird, which provides drinking
water for Norman and surrounding areas.
“There is a very big difference in runoff,” said Shanon Phillips, water
quality division director of the Oklahoma Conservation Commission,
which oversees conservation practices in the state. “If we can make it
work in entry-level homes in Oklahoma, then I think we can make it work
in other places.”
McKown said he got the idea for green development while in Prince
George’s County, MD, for a conference on stormwater. But the Chesapeake
Bay region has few, if any, side-by-side projects like this one,
according to Cecilia Lane, stormwater coordinator of the Chesapeake
Stormwater Action Network. More rare, still, she said, is to find a
project that scientists are monitoring under a multiyear plan as
Oklahoma University is doing at Trailwoods.
“It’s so expensive to do the monitoring, and then to collect the data,
and then to show a difference,” Lane said. “We have seen studies that
show one specific thing. It’s so challenging because there are so many
variables.”
Brandon Holzbauer-Schweitzer, the graduate student who is monitoring
and testing the water samples, said he only knows of one other place
that is testing stormwater practices side by side: a suburb of
Milwaukee, WI. He said that he hopes the Trailwoods results will inspire
other communities to attempt a similar plan and get the same
reductions.
“We hoped that it would show something like that, but I wouldn’t have
expected to have that much phosphorus retained in the system,” he said.
“It makes sense, because the plants took up more phosphorus, but it
still was kind of impressive that it removed that much.”
Other benefits to the green side of the development, McKown said,
include lower energy bills, less need for landscaping and, he hopes, a
sense of the greater good. To that end, all of the streets in the green
part of Trailwoods are named after characters and terms from Dr. Seuss’
“The Lorax.”
Houses in Trailwoods started at $110,000, and the green ones did not
cost more, though they did cost more to build, because, McKown said, he
had to learn how to construct rain gardens and rain barrels.
“We have gotten good enough at building rain gardens that don’t blow
out,” said McKown, who owns Ideal Homes with his brother. “But we would
like to get the cost down.”
The rain gardens McKown built cost $8,000; he would like to build them for $1,000 apiece.
The monitoring was also a challenge. The university worked with the
developer and the Oklahoma Conservation Commission to set up the
monitoring stations, which consist of a stream gauge checking the
nutrient concentration from two holes in a flume. But the project’s
beginning coincided with Oklahoma’s drought, and there wasn’t much to
measure until last spring. The monitoring project concludes in December.
Still, McKown and the conservation commission members are excited about
the results, and hopeful they will be able to secure funding for more
monitoring at Trailwoods, as well as replicating the project elsewhere.
Already, the commission has worked to install several wetlands and
restore a grass area to a wild meadow with the support of the broader
Norman community. They are, noted commission communications officer
Robert Hathorne, the same kind of practices that farmers have been using
and calling best management practices for decades. They can still be
that for stormwater, whether managers call them that, or green
infrastructure or something else entirely.
“These practices that we achieve success with on the landscape level we
are now applying to a landscaping level,” Hathorne said. “These
stormwater areas, they are just streams in an urban area.”
