Analysis of Water and Sediment from Plum Creek to Investigate Potential Sources of Fecal Contamination.

Water quality standards are necessary considerations in assessing water bodies and allocating state resources. Total Maximum Daily Load (TMDL) limits set forth by the Minnesota Pollution Control Agency (MPCA) set parameters for maximum concentrations of pollutants a water body can contain, receive, and still maintain basic water quality standards. In 2009, Plum Creek in Stearns County, MN was found to have elevated levels of Escherichia Coli, qualifying the water body for the Impaired Water Body List. This listing incited action of the local community who performed preliminary research in order to identify the source of contamination. Regular citizen water sampling for E. coli testing has been performed since 2014 and recent bacterial source tracking performed on water samples tested negative for source-associated fecal gene biomarkers of ruminants, poultry and humans. This information along with land use data from the watershed, indicating no nearby feedlots, septic systems, biosolids applications, presented a challenge in identifying fecal contamination sources. The objective of this project is to expand on previous study by performing additional intensive sampling to determine potential sources of fecal contamination. Increased water sampling will be performed in collaboration with local citizen sampling to increase sampling frequency and spatial resolution along previously-nonsampled portions of the creek. Additionally, this study will analyze E. coli in stream sediments and water samples to determine the possibility that increased fecal contamination in water may be from naturalized populations of E. coli in stream sediment. These results will assist local regulators in elucidating potential sources of contamination, necessary to effectively target resources and mitigation efforts.