News - Conover Station Stormwater Treatment System – Conover, NC
October 1, 2012 – Conover Station is an active brownfield re-development project located on the site of a former furniture plant just south of downtown Conover, NC. Under a contract with the City of Conover, JEWELL Engineering Consultants designed the stormwater system that manages runoff from the site as well as runoff from a large portion of Conover’s downtown area. Stormwater runoff from the downtown area is conveyed by a wide swale through the upper half of the site. This swale is unique in that it serves as both a stormwater treatment system and primary stormwater conveyance. The swale includes three stone drop-pools to dissipate excess energy and a continuous French drain to de-water the swale and drop pools following rain events. Runoff from the swale and French drain discharges into a collection structure connected to an existing culvert under 5th Avenue.
Discharge from the 5th Avenue culvert enters a concrete diversion structure that allows stream base flow to pass unimpeded while diverting mandated first-flush flows into a two-cell stormwater wetland system for treatment. Stormwater pollutants are removed as the runoff passes through the upper and lower cells before being discharged back into the stream. The diversion structure allows flood flows to pass directly downstream. Site topography required the use of two wetland cells and the upper cell contains a forebay to trap sediments. A unique feature of the diversion structure is that it also doubles as an emergency spillway for the upper wetland cell. Each wetland cell is designed with shallow and deep pools, as well as native aquatic plants, grasses and shrubs, to mimic both the function and image of a natural wetland. To maintain wet conditions even during drought, each wetland cell is hydraulically connected to natural ground water.
To round out the project and maximize stormwater quality benefits, a riparian buffer will be constructed along the northeast side of the existing stream to control runoff and manage pollutants as it flows to the stream. The entire site is being blended into a passive, park-like recreation area that includes walking trails, wetland boardwalks, interpretive signage, a children’s playground, and community gazebo.
The project was funded in part through a grant from the Clean Water Management Trust Fund.