A May 22 article and its headline misstated the amount of green space that is disappearing to development each day across the 3,000-square-mile Washington region, according to the study's authors. The amount is 28 to 43 acres. (Published 5/24/04)

The greater Washington region lost nearly half as much green space to development from 1986 to 2000 as it did in its entire prior history, according to a soon-to-be-released study.

Each day, 28 to 43 square miles of green space in the region are overtaken by the builder's bulldozer, say the authors of the study, co-sponsored by the Metropolitan Washington Council of Governments and the National Park Service.

"I'm amazed at the rate it's disappearing, and it seems to be regionwide," said Brian LeCouteur, senior environmental planner and urban forester with COG. "This isn't a question of tree-hugging; it's about breathing clean air and drinking clean water.

"It's about protecting where we live."

The study, called the Green Infrastructure Demonstration Project, used satellite imagery to map a 3,000-square-mile area, defined by the outer borders of Prince William County on the south, Frederick County on the north and Prince George's and Loudoun counties on the east and west. By comparing detailed aerial images dating back to 1986, the authors were able to track the rate of development over a 14-year period and compare it with what existed previously. They also organized the open space into a dozen types, from croplands to wetlands, to better assess its quality.

One recent morning, LeCouteur unrolled one of the tabletop-size maps outside his office. Developed areas are color-coded by year, with the most recent portrayed in purple. At first, there isn't much purple visible. But upon closer scrutiny, thousands of violet dots emerge like paint spatters, each representing a strip mall, a subdivision or a parking lot built between 1996 and 2000.

"It's like looking at the night sky," LeCouteur said. "The more you look, the more you see."

Across the region, the percentage of developed land increased from 12.2 percent before 1986 to 17.8 percent in 2000. By now, LeCouteur estimates, the proportion of developed land has topped 18 percent.

The maps show what looks like a reassuring amount of green -- yet, LeCouteur pointed out, that's deceptive. As home builders avoid the stricter rules governing density in close-in suburbs and development moves farther from cities, swaths of open space surrounding the metropolitan area are broken up with islands of homes and shopping centers.

While scarcely visible on the map, this atomized development leaves fewer areas big enough to support wildlife, creating problems ranging from deer overpopulation to destruction of native plant species.

"When we think about green space, we don't have any real master plan for what places we need, why we need them and how they connect," said Glenn Eugster, assistant regional director of the National Park Service's Partnerships office in Washington. "We tend to do a little park here, a wetland there. The hope is that at some point all these dots will be connected.

"But right now it really is a tyranny of small decisions."

Michael T. Rose says it's those small decisions -- not developers -- that are mostly to blame for the shrinking of the green. Rose, 60, of Potomac, founded Michael T. Rose Cos., based in Laurel, in 1975. Since then, the residential home developer has earned kudos from environmentalists for projects that spare mature trees and use environmentally sensitive materials and construction methods. But he says archaic zoning laws make such approaches time-consuming.

"The pressure to go along with the codes the way they've always been makes it easier if the trees are gone," he said.

Take Northridge, his development in Bowie. Built in 1988, the community has helped earn the company several environmental awards for design amenities such as a man-made lake, traffic islands and narrower clearances around homes that save trees, and a grass-lined drainage system.

"We had a three-inch book requesting [development-related] waivers, and it took 31/2 years to get approval" for the project, Rose said. "There are still many areas that don't know how to respond when the developer says, 'I want to save a tree and have open space.' "

Another problem, he said, are building codes that focus almost solely on density, instead of innovative ways to cluster more homes in population centers. The codes drive up housing prices and contribute to sprawl, he said.

"We've got roads and transport and sewer and water that could be upgraded, instead of pushing people over the Pennsylvania line," he said.

By comparing the green space inventory detailed on the maps with their own land-use plans, local governments can guide future development and maximize the amount and size of green space they have left, LeCouteur said.

The authors of the study hope it will someday underpin a regional development plan, as an alternative to the patchwork of local plans. In a recent report, Eugster wrote that although more than 311,036 acres of open space will have gone under the bulldozer from 1990 to 2020, no major green space protection initiative exists in the region.

Eugster offers the country's interstate highway system as a model. "It's a coordinated, connected system that clarifies the role of the feds, state and local governments and the private sector," he said. "That's a good model for green infrastructure, too."

New housing in Urbana, in Frederick County. With development dotting the landscape, experts say, fewer areas are big enough to support wildlife.