WATER QUALITY ASSESSMENT TOOLS: A COMPARATIVE STUDY OF DIFFERENT ASSESSMENT TOOLS

Achieving high water quality is one of the major goals of stream cleanup and monitoring, especially at recovering agricultural sites. It is, therefore, imperative to frequently assess the water quality of streams at such sites. Surface water is typically assessed using biological indices (fish, macroinvetebrates, phytoplankton), physiochemical parameters (dissolved oxygen, temperature, pH, nutrients and other chemicals) or physical habitat assessment tools. Each of these tools provides insight into the causes of poor water quality in a given water body and can help guide restoration efforts. The goal of this study is to compare different assessment tools along Tobler Creek, located in the lower Oconee watershed in Milledgeville, Georgia. The creek is listed as impaired based on biological indices but the causes are not yet known. This project also assesses the role of hyporheic interactions on the water quality with respect to nutrients and algal concentrations. Two sites along the creek and one site in a nearby pond were sampled for water quality. Preliminary results show a discrepancy among the assessment tools. An initial visual assessment shows habitat degradation due to bank erosion and accumulation of woody debris. Despite the creek being listed as impaired based on a fish study, all the physiochemical parameters, nutrient and heavy metal results fell within the healthy range. Biomass measurements of primary producers like Cynobacteria, green algae and diatom concentration are also low and all primary producer communities are dominated by diatoms. Preliminary data on fish studies from the sites confirm the discrepancies. Since this site is located on land that is recovering from agriculture, nutrient fluxes might be unreliable and hard to predict.