Assessment of Common Nutrient Levels and Water Quality in Town Run Tributary of the Potomac River

Abstract

Town Run is a tributary flowing through residential and agricultural areas of Shepherdstown. Despite being an untreated water source of the local drinking water from the Potomac River, it’s unknown how conditions along the length of the run influence the quality of the water. This ongoing study aims to monitor and analyze fluctuations in water conditions across seven designated sampling sites. Abiotic parameters, including temperature, pH, salinity, dissolved oxygen, nitrate (NO₃⁻/N), phosphate (PO₄³⁻), and chloride (Cl⁻), are measured using a water meter probe and HACH test kits. In addition, bacterial counts are estimated by collecting water samples from each site and plating them on Eosin Methylene Blue (EMB) and Tryptic Soy Agar (TSA) to approximate bacterial abundance and search for the presence of coliform bacteria, especially Escherichia coli. Patterns in water temperature predictably correlate with air temperature and vary depending upon the season. Concentration levels of NO₃⁻/N, PO₄³⁻, and Cl⁻ have consistently fallen below detection level or been detected at such low amounts that they have been ruled as insignificant effectors of the water quality of Town Run. Further investigation is required to understand fluctuations in pH, salinity, and bacterial colony growth. Town Run flows over limestone rich areas, which we predict will be responsible for the variations in pH. Work is ongoing to detect calcium to verify this explanation. Variations in salinity following rain and snow events are also of future interest. This study provides insight into the dynamic interactions affecting Town Run’s water quality and contributes to the understanding of the effect of communities on urban water ways.