Duke is expected to begin construction in June on a large-scale water reclamation pond near Erwin Road between Circuit Drive and Towerview Road.
Once operational, the pond will collect rainwater and runoff from 22 percent of the main campus area for use in a nearby chilled water plant, which pumps water across campus to cool buildings.
The pond initiative is another significant sustainable step by Duke since the record drought in 2007. It's expected to save about 100 million gallons of potable water a year.
"In the years following this area’s historic drought, Duke has continued to innovate and find ways to conserve a precious resource," said Tallman Trask III, Duke's executive vice president.
The $9 million reclamation pond will sit on a 12-acre site that will provide a place for education and research. Plans call for a pavilion, boardwalk, nearly mile long walking path and amphitheater with lawn seating. Construction will take about a year.
Project managers are working with state and federal agencies on permits and are consulting with the Duke University Wetland Center to select native plants that thrive at varying pond depths under dry and wet conditions.
"The aquatic shelf is going to be unique," said Stephen Carrow, project manager for Facilities Management. "We want plants that can tolerate being wet and dry, and a woodland area that ties back into the forest."
Work will begin this week on removing some trees for a construction entrance on Towerview Drive, about halfway between Erwin Road and Circuit Drive. Around June, trees will be removed to situate the pond and its supporting structures, including a pump house and 20-foot tall dam. Some trees will be replanted, while others will be reused as lumber for decking, handrails and other structures at the site. In addition, some trees will be used for hardwood mulch around paths and plantings.
"Careful planning and design have been done to save as many trees as possible," Carrow said. "For example, instead of going to a Home Depot to buy a sheet of plywood, we're going to take rough sawn lumber and use that on-site."
Any surplus wood will be sold to an area mill, and the proceeds will be donated to the Duke Forest.
Considerable planning has also gone into other vegetation at the site. The pond’s edge will include 40 herbaceous species that can tolerate hot, dry summers or soaking wet conditions. Plans also call for 21 different shrubs and 60 tree species, including maples, cedars and magnolias.
The pond will be incorporated into a shallow stream that runs through the site and will hold about 6.7 million gallons of water, at up to a 10-feet depth.
"When complete, the pond will be an amenity at Duke, but it will also have a sustainable benefit and educational component as a place to showcase native plant life in a natural setting," Carrow said.