STREAM CONTAMINATION: ESCHERICHIA COLI IN MIDDLE TENNESSEE

Three tributaries of the Cumberland River in Middle Tennessee were placed on the Environmental Protection Agency’s 303(d) list in 2006 due to Escherichia coli (E. coli) measurements above the maximum allowable contaminant levels. Placement on the 303(d) list prohibits municipal usage of water from Mansker’s Creek, Slater’s Creek, and Lumsley Fork. Sources of the contamination may include, but are not limited to: municipal sewage, agricultural runoff, sanitary waste discharge, improper trash disposal runoff, leakage of septic systems, animal waste, and storm water runoff. Multiple occurrences of exposed pipes, sewage drains and excessive trash have been observed in two of the three streams. Each of the three streams have been monitored periodically since the spring of 2013, with analyses of water temperature, pH levels, total dissolved solids, electrical conductivity, nitrates, dissolved oxygen, and alkalinity to determine whether chemical trends are present. Weekly monitoring and water sample collection have been performed during 2015. A DNA-detection technique known as Polymerase Chain Reaction (PCR) is being utilized to detect the presence of E. coli in collected water samples. To date, PCR results indicate very little presence of E.coli. In order for the streams to be removed from the 303(d) list, allowing for unrestricted water usage, the primary source(s) of contamination must be determined prior to the enactment of remediation processes.