Feces-Associated Bacterial Contamination of the Dry Creek Watershed

1. A B C Feces-Associated Bacterial Contamination of the Dry Creek Watershed Dr. Geoffrey W. Gearner and the Fall 2007 Class of the Principles of Microbiology Morehead State University • Introduction • Fecal contamination (human and animal waste) comes from native wildlife, domesticated animals, and humans. • Sources include straight pipes, failed household septic systems, and farmland run off of animal waste. • The amount of certain bacteria that are associated with the feces of mammals, birds, and humans can be measured from water samples collected from Dry Creek. • At present, we test for fecal coliform, Escherichia coli (E. coli), and fecal enterococci (streptococci) bacteria. • Results • In the present study, we evaluated bacterial densities in eight locations along the Dry Creek watershed over a 30-day period. The results will be used to establish a baseline database, and to refine our identification of sampling sites, and to help determine the sources of fecal contamination. • All bacterial counts varied over the range of the sampling sites and over time (Fig. 4). • The highest counts observed followed a significant rain event on 23-24 October 2007. • Fecal coliform to fecal streptococci (enterococci) indicate that the possible source of fecal contamination is animal (FC:FS < 0.7) or a mix of animal and human (FC:FS = 0.7 – 4.0). • Analysis of the data show that none of the sampling sites in the watershed exceeded State or EPA standards for primary contact recreational water for fecal coliform bacteria, however, one of the sites (Nichols Branch) did exceed EPA and State standards for E. coli (Fig. 5). • Five of eight sites sample exceeded EPA standards for fecal enterococci bacteria. Discussion The monitoring of fecal-associated bacteria in the Triplett Creek watershed, including the Dry Creek basin, has been an ongoing project at Morehead State University. The development of improved methods for detecting and enumerating these microbes have provided us with a better picture on the sources of fecal contamination our watersheds. The preliminary results of our water sampling indicate that current practices in the Dry Creek watershed is causing fecal contamination to reach our waterways . The Commonwealth of Kentucky has designated Dry Creek as an impaired stream, having been placed on the Second Priority 303b list. Continued bacterial monitoring will assist with the identification of possible sources of fecal contamination. The development of a watershed-based plan will address contamination issues and gauge the effectiveness of remediation efforts. The overall goal of the watershed-based plan is the removal of Dry Creek from the impaired streams list. Figure 1. Examples of bacteria grown in the lab from water samples. Recent Bacterial counts in Dry Creek sites, Fall 2007 Dc-06 Dc-05 Dc-04 Note: The bacterial counts highlighted in RED have exceeded water standards. Figure 2. Map of the bacterial sampling sites in the Dry Creek watershed. Legend: Co-01=Catron#1; Co-02=Catron#2; Co-03=Jenning’s Septic; Dc-02=Lambert Branch; Sr-01=Amanda Bridge; Dc-04=Nichol’s Bridge; Dc-05=Ravenswood Bridge; Dc-06=Tile Storage Road. Contacts Katie Holmes, Watershed Program Director April Haight Kentucky Waterways Alliance MSU’s Center for Environmental Education 222 Bakery Square LC 101A, IRAPP Louisville, KY 40206 Morehead, KY 40351 (502) 589-8008 (606) 783-2455 This project is funded by non-point source pollution grant by the Federal Environmental Protection Agency, Kentucky Waterways Alliance, and Morehead State University