LAND USE PRACTICES AND ELEVATED LEVELS OF ESCHERICHIA COLI IN THE COOSAWATTEE RIVER, GEORGIA.

Because fecal coliform bacteria levels have exceeded Georgia Water Quality Standards over the last ten years, portions of the lower Coosawattee River, Georgia, are listed as impaired by the state of Georgia and do not support its recreational-use designation. The suspected cause of elevated fecal bacteria is the location of agriculture areas adjacent to the river's bank and poor management practices. Escherichia coli (E. coli) bacteria are a subset of the fecal coliform bacteria group and because fecal coliform bacteria were elevated in the lower Coosawattee River, were probably elevated as well. Fecal coliform and E. coli bacteria are not typically pathogenic in water, but indicators of fecal contamination whose presence increases the possibility of illness in humans using the water. In order to assess E. coli densities in. the Coosawattee River, 60 water samples were collected on the main river (some near tributary inflow) and analyzed along 75 km of river. Eight of the 60 water samples analyzed for E. coli produced inconclusive results due to improper incubation temperatures. The E. coli results were plotted on satellite imagery and compared to elevated levels and land use. In this paper, elevated levels are those that are >235 cfu/100 ml as established by United Stated Environmental Protection Agency (USEPA) for single-sample beach criterion. Of the samples collected, 15% exceeded the USEPA criterion for E. coli. All of the samples containing > 235 cf u/100 ml were collected in the lower Coosawattee and are adjacent to agricultural land use. This study makes reiterates unacceptable levels of E. coli contamination in the lower Coosawattee River due to non-point sources. [ABSTRACT FROM AUTHOR]