GROUNDWATER HYDROLOGY AND NITROGEN REMOVAL IN A DYNAMICALLY ENHANCED STORMWATER TREATMENT WETLAND

Wetlands are highly studied and valuable as remediation sites due to their high nitrate removal efficiency. This research examines the extent to which denitrification is occurring at an innovative enhanced wetland. Results from the creation of laboratory wetland emulated microcosms and field measurements will be presented. Preliminary modeling of denitrification dynamics is being conducted to determine if subsurface removal of nitrogen is a significant factor in this treatment system.

The study site is a riparian wetland that has been enhanced by the City of Greensboro, NC in order to reconnect a riparian wetland with an incised creek, 303(d) listed South Buffalo Creek. The wetland is the City's primary BMP to address the water quality issues of a highly urbanized watershed (31% impervious surfaces). Furthermore, the impervious area of the wetland's watershed is expected to continue to increase drastically, thus the functioning of this wetland has significant importance. The primary enhancement to the wetland is a conditional response flow control gate that temporarily deploys after rainfall events based upon stream stage. Research that examines wetlands with unique enhancements, such as this regionally uncommon flow control gate, can provide information to improve the wetland's functional abilities.