An Assessment of Coliform Bacteria in Water Sources Near Appalachian Trail Shelters Within the Great Smoky Mountains National Park

Objective: Hikers and campers are exposed to risks while in the wilderness. One of these risks is the possibility of contracting an illness, including infectious diarrhea. This project tested for coliform bacteria in water samples taken near popular Appalachian Trail shelters.

Methods: Water was collected from access points within the Great Smoky Mountains National Park. Samples were collected in sterile bottles and inoculated on a commercially available coliform detection kit for quantitative determination of total coliform and Escherichia coli counts.

Results: Water samples were taken during summer and fall seasons. During summer, 7 of 10 samples were positive for coliform bacteria and 6 of those 7 for E coli. The most probable number (MPN) of colony-forming units (CFU) for coliform bacteria ranged from 0 to 489 CFU/100 mL, with the MPN for E coli varying from 0 to 123 CFU/100 mL. These data differed from the fall collection, revealing 3 of 7 samples positive for coliform bacteria and 1 of those 3 for E coli. The MPN of CFU for coliform bacteria in fall samples varied from 0 to 119 CFU/100 mL and 0 to 5 to CFU/100 mL for E coli.

Conclusions: Environmental Protection Agency drinking water standards set the standard of 0 CFU/100 mL to be considered safe. This analysis of water samples along the Appalachian Trail emphasizes that the majority of water access points require treatment during the summer season. Coliform burden was not as high through the fall months. These data suggest one infectious disease risk for wilderness travelers.