environmental chemistry, Lake Michigan, E. coli, water quality, public health, microbiology, qPCR, Annis Water Resource Institute


Biology | Environmental Chemistry | Microbiology


Dr. Richard Rediske


An investigation of Escherichia coli concentrations in a west Michigan stream was conducted to determine sources of fecal contamination that impact water quality. Little Black Creek (LBC) is located in Muskegon County and discharges into Lake Michigan at the P.J. Hoffmaster Campground Beach. Often referred to as an “indicator bacteria,” water contaminated with E. coli has a high probability to contain other enteric pathogens as well. Beach water testing in 2020 using Colilert-18 methods revealed E. coli levels of 579 cfu/100mL in the creek discharge area that exceeded total body contact criteria of 300 cfu/100mL. A follow-up study of the creek found concentrations of E. coli exceeding the total body contact criteria at multiple locations. Samples collected after a rain event found E. coli levels > 2,400 cfu/100mL in the mouth of LBC. Further investigation into sites of LBC nearest to the campground’s sanitary facilities found E. coli levels of 860 cfu/100mL where a drainage pipe empties into LBC. Spatial and temporal trends of microbial data will be discussed for the beach and the creek. Results of quantitative polymerase chain reaction (qPCR) using the human marker, HF183 were negative, suggesting the bacterial contamination was from wildlife sources.