"By restoring the natural flood plain that used to be here before the onslaught of urban development, we'll recreate a healthy wetlands ecosystem that sops up pollutants and improves wildlife habitat," said Curtis Richardson, director of the Wetland Center and professor of resource ecology at the Nicholas School.

The project will include re-contouring and replanting more than 2,000 feet of degraded stream, and constructing an earthen dam and four-acre stormwater reservoir. Duke Forest's Al Buehler Trail, located near the Washington Duke Inn and Golf Course, will pass along the dam.

Stormwater from about 1,400 acres of Durham, including much of Duke's campus, drains into Sandy Creek, carrying heavy concentrations of sediment and urban pollutants. Sandy Creek is a tributary of New Hope Creek, which meets all state pollution standards when it enters northern Durham County but often is in violation by the time it leaves southern Durham County bound for Jordan Lake, part of the Triangle's drinking water reservoir.

A hike along Sandy Creek's current path, as it flows under N.C. 751 east of its intersection with Duke University Road, reveals a sediment-choked streambed with crumbling banks, downed trees and vegetation too sparse to retain soil during heavy downpours. During big storms, nitrogen and phosphorus levels in the water can reach three to five times the state limits.

Increasingly large amounts of land in Durham are covered by impervious paving. Over the years, torrents of storm water diverted by this paving have cut deeply into Sandy Creek's banks, eroding its natural bends and creating "a straight chute for sediment and pollution," Richardson said. "We've lost the bends and contours that allowed the water to overflow into surrounding bottomlands, where wetland plants and soils could absorb the majority of the pollutants."

Richardson's team will address that problem by engineering a new, more naturally meandering streambed for Sandy Creek and filling in its old channel. Creek banks and low-lying areas will be re-contoured and planted as hardwood wetlands, which researchers believe will remove up to 70 percent of the creek's sediment and nutrients.

The new dam and reservoir to regulate stormwater will replace a deteriorating dam farther downstream. A short stretch of the Art Buehler Trail will be re-routed across the dam to provide unobstructed views of the reservoir, wetland and wildlife. Trail closures during construction will be brief, Richardson said, and advance notices will be posted at the trailheads.

A four-acre wooded area to be flooded by the reservoir will be cleared in coming weeks, and other trees that will not survive the raised groundwater levels around the reservoir and new flood plain also will be removed. Cleared trees will be used as "rootwads" to help stabilize the new stream channel and to provide habitats for fish. New wetland trees will be planted to replace any that are removed.

"Our goal is to recreate an ecosystem similar to what you would have found here 75 to 100 years ago," Richardson explained. He and his team have completed a biological census of the area and collected three years worth of pre-restoration data on its soil, water, plants and wildlife.

Besides being an example of a rare Piedmont wetland, the eight-acre ecosystem will provide a site for research on biological diversity, hydrology, mosquito control, invasive plant species and other environmental concerns, Richardson said.

"What we learn here will benefit many wetlands and watersheds nationwide," he said.