For 30 years, the narrow swath of woods along Glade Stream in Reston has been an oasis for nearby residents as bulldozers cleared away thousands of neighboring acres for homes, shopping centers and parking lots.

Untouched except for a dirt trail, the forest, which stretches for about five miles, reminds residents of the way it was before Reston became one of the nation's largest so-called planned communities. It was even dubbed Reston's "nature center."

But then in January, residents living along the stream valley's ridge say they were startled to find a tractor with a backhoe plowing a meadow in the woods. Although it was to build a wetland pool and not another dreaded development, nearby residents say they were outraged nonetheless.

"I couldn't believe it," said Joan McWilliams, whose home sits on a ridge overlooking the stream valley. "It's part of the Chesapeake Bay Preservation Area and it's supposed to be left alone."

In a community where cutting down a wasp nest has political implications, the construction of the wetland pond has divided the community and has stirred stinging attacks and equally venomous counterattacks.

The small pond--about the size of a backyard swimming pool--and a storm-water retaining pool, also called the rain guard, built about 25 yards away have riled residents and have prompted a bitter debate over what to do with the last large undeveloped parcel of land in Reston.

On one side are the residents who live in homes adjoining the Glade Stream Valley that snakes east to west just north of Lawyers Road. They say the narrow 70-acre swath of forest should be left untouched as a nature preserve and not "Disneyized."

They have accused Robert E. Simon Jr., founder of Reston, of masterminding plans to turn the parcel into an education park open to county residents that would be similar to nature education centers found in Europe, where parts of the woods act as nature exhibits. In the process, they say, the project is damaging an environmentally sensitive area.

"He wants to make it into a regional park where people from all over can come," said Vera Hannigan, a Reston Association board member who opposes the project and has called for restoring the area to the way it was.

"People coming from all over can be detrimental to the fragile area. He's going to ruin a very fragile, beautiful place."

Simon says the residents are "flat wrong" and has come out strongly in defense of Reston Association officials who approved the project.

"They were done to resolve rain runoff problems. That is all," said Simon, who has called the residents protesting the project "ideologues who are throwing dust in the eyes of the public."

"It's not like we cut down a whole bunch of trees. We didn't damage anything. We just made the project a little better," he said. "I wish they would just shut up."

Both sides agree on one thing. The ultimate fate of the preserve will be left to Fairfax County officials, who must decide whether the wetland pool and the rain guard should remain or should be taken out and the area restored to its previous condition.

"We are essentially trying to clear up the issue after the fact," said John Friedman, special projects director for Fairfax County, who is assessing the project and must decide whether it should stay or go.

County officials entered the fray in the spring after residents complained about the project, accusing the Reston Association, which maintains public areas in the community, of violating county land-use ordinances.

The county agreed and cited the association with violating the Chesapeake Bay Protection Ordinance. A cease-and-desist order was issued and the association has been given the choice of either restoring the area to its original condition or applying for an exemption to the ordinance.

Reston Association officials, who say they were merely trying to address erosion problems and to keep water away from the walking trail, said they will file for an exemption. Part of the work included installing drains to divert water under the trail and into the excavated area, officials said.

"It's really just to retore the pathway and at the same time create a habitat for the wildlife," said Larry Butler, director of the Reston Association's park and recreation department.

Reston officials said that the project initially entailed work on less than 2,500 square feet, which doesn't require filing for an exemption from the county. But during work, Butler said, they found a large area filled with poison ivy that had to be cleared, enlarging the work area to about 3,000 square feet.

But residents aren't convinced.

"They seem to be trying to fix a problem when there isn't any," said Leonard Konikow, a certified hydrologist who is a resident in the area. "There is no evidence of significant erosion. There is no discernible problem."

McWilliams added, "That poison ivy story was cooked up in April after we complained."

In addition, residents say that since the wetland pool was built, they've gotten more unwanted pests.

"This is the first time in 20 years we've had mosquitoes," said Joe Jahoda, who lives on Drop Forge Lane. "We can't even cut down our own tree without having to fill out tons of paperwork and they just come in and do it without telling anyone. It's ridiculous."

Meanwhile, Reston officials have posted signs in front of the wetland pool and the rain guard, explaining the project to visitors walking along the trail.

"Uncontrolled stormwater is eroding the trail and creating impassable muddy areas," the sign posted in front of the rain guard says. Next to it is a new wooden bench.

The sign in front of the wetland pool, which as a result of the drought now resembles a puddle, explains that the pool "restores biodiversity to the nature center and provides wonderful habitat."

It adds, "Hope you will enjoy it throughout the season."

CAPTION: Reston Association official Larry Butler, center, explains the need for the pond to Fairfax County officials. Dawn Biggs, foreground, also works for the association.