Seminar: Jason Green and Katharine DeVilbiss, Division of Water Resources

“To Solarbee or not to Solarbee ― that is the question.” The NC Division of Water Resources is currently performing monitoring to evaluate the potential of solar powered mechanical circulation (SolarBee) to reduce nutrient related impairments for Jordan Lake in Chatham County, NC. A preliminary assessment was conducted on historical, and project period water quality data to investigate efficacy of the Jordan Lake Nutrient Mitigation Demonstration Project. Overall success of the demonstration project will be measured by comparing concentrations of surface pH and photic zone chlorophyll a (Chl a) to water quality standards using the current assessment methodology for impairment as approved by the Environmental Management Commission in 2013. Water quality monitoring data were used to answer two questions: Did water quality improve in areas of the lake where SolarBees were deployed? This question was addressed by analyzing pH and Chl a values and percent exceedances during the SolarBee project against historical trends, in addition to statistically comparing results for pH and Chl a among sites spatially in the immediate vicinity of SolarBees (project treatment) versus outside of the project area in Jordan Lake (control).  Were there shifts in phytoplankton community composition at sites where SolarBees were deployed? This question was addressed by constructing algal similarity indices based on group densities among treatment and control sites, as well as statistically comparing relative abundances of Cyanobacteria and Chlorophyta among treatment and control sites.