Cooperative Extension Neuse Team member converts former high school pollution eyesore to functioning, dynamic wetland classroom |
|
At Smithfield-Selma High School, an eyesore ditch filled with broken concrete, algae and trash transformed into an attractive wetland is now a lush and growing ecosystem.
Installed in 2001 after a soggy soccer field sparked interest in stormwater management at Smithfield-Selma Senior High School, the wetland treats and slows runoff, limits downstream flooding and erosion and is a high school and university outdoor classroom. Seeking advice on how to drain the field, Kenneth Bateman, county extension director in Johnston County, contacted Neuse Team members Bill Lord, Franklin-county-based area environmental agent, and Bill Hunt, NC State University Biological and Agricultural Engineering stormwater specialist. Extension agents, concerned about the amount of nutrient leaching coming off the campus, envisioned a double use for this wetland. “Maybe we could use this to do some actual monitoring to see if we did have some leaching [of pollutants],” says Bateman.
The next step was to convince others that the stormwater wetland would be perfect for treating the school’s runoff. Says Bateman, “It just wasn’t one agency or organization. It became a networking venture for the board of education, the school and school administration and the Town of Smithfield.”
The partnership didn’t end there, but continued to grow: the N.C. Cooperative Extension Service, the NC State Department of Biological and Agricultural Engineering and the Natural Resources Conservation Service also are involved. Site plans for the wetland were created by NC State student Amy Lewis as part of her senior design project, with Hunt advising. The N.C. Division of Water Resources and the Neuse Education Team provided $15,000. Now the wetland treats stormwater from nearly 26 acres of SSSHS’s watershed. Runoff is directed into the wetland through both from the parking lot surface and two subsurface storm pipes that drain the buildings and grounds. Says Lord, “Parking lot surface water tends to be hot and high in phosphorous, and the subsurface water tends to be cooler and higher in nitrogen.”
Excessive nitrogen and phosphorous harm water quality, and drastic water temperature changes can injure fish and other organisms, so the state monitors the SSHS wetland for its ability to reduce pollutants in stormwater. Studies show a drastic reduction in nitrate, total nitrogen and total phosphorous concentrations as well as a temperature drop in stormwater that has been treated by the wetland, says Lord. How does a wetland reduce pollutants?
“In a wetland,” Lord explains, “you get plant uptake of nutrients, you get a fair bit of transformation through processes like de-nitrification, and you get nutrient and sediment deposition because of all the filtration going on. So you have this complex plant, animal and microbe community at work there.” For instance, three deep pools take groundwater input and stay wet during droughts to support aquatic plants, mosquito fish and other organisms that aid in treatment. And 29 species of native wetland plants stabilize wetland soil and slow and treat stormwater: including cardinal flower (see photo) and duck potato. The project has not been without challenges, especially since the word “wetland” can evoke images of a swamp — stagnant water full of mosquitoes and other health hazards – in the minds of those unfamiliar with the concept.
But through careful management and maintenance of a very diverse ecosystem — water level manipulation, invasive cattail control, mosquito fish stocking — the wetland was established without Lord, a trained entomologist, spotting a single mosquito larva. Education warmed public’s perception of the wetland: the site was the focus of a stormwater professionals’ statewide training, a workshop with N.C. Department of Transportation engineers and three international tours. “It’s been of tremendous educational value to us in our stormwater program and to the school in its environmental biology program,” says Lord. When Ellen Ennis started teaching about our environment at SSSHS several years ago, one environmental science class had partial enrollment. Now all eight classes are full. “Students learn the difference between abiotic and biotic systems. They get to get out there and find out what is really alive,” says Ennis. Grab a camera and a wetland plant book, and learn for yourself. at SSSH Wetland, 700 Booker Dairy Road, Smithfield, N.C. For information: Bill Lord, 919.496.3344. -- Lilly Loughner |
||||||||||||||
|
||||||||||||||
