CHICAGO — It's like a scene from a peaceful meadow: Where wildflowers bloom and the bees are busy. But to reach this slice of Eden, one doesn't travel out of town, one travels up, 12 stories up.
"I talked about building a green roof," says Chicago Mayor Richard Daley, "and everybody kind of looked at me whether or not I kind of lost it, ha ha ha."
But the crazy idea is paying off. Since Chicago installed a 20,000 square foot "green roof" atop City Hall five years ago, the city has saved about $25,000 in energy costs.
"Because there are plants on it, it's cooler than a regular flat, black roof," says Robert Berghage, an associate professor of horticulture at Penn State University.
Berghage's research has shown there are many benefits to going green.
"The water from the flat roof was about here," Berghage says as he demonstrates at a water measuring tank. "The water from the green roof is down here."
The plants can drink 60 percent of dirty rain water before it can overflow local sewer systems, soaking up some of the costs businesses pay to control storm water runoff.
"Anything you can do to get more plant material in the city is going to make a big difference in helping to make our cities more livable," says Berghage.
Ruth and Scott McElroy of Norfolk, Va., liked the idea so much, they took it home. They paid $4,000 to install a green roof.
"In the first month we had the roof installed, we saw our air conditioning bill drop by about $25," says Ruth.
It's not very often a simple idea comes along that's not only good for the environment but also the bottom line — and that's exactly what green roofers are hoping big business picks up on.
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In Dearborn, Mich., 10 acres of vegetation tops a Ford assembly plant. Green roofs are sprouting up on stores, schools, even a few dog houses.
Back in the Windy City, more than 250 buildings are going green on top.
"As everybody talks about the environmental movement, they're always pushing their finger someplace else," says Mayor Daley. "They should just turn their finger right into their own backyard, their own city."
A green revolution's underfoot, and it's looking down on America from above.
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