|BRADSHAW, J - Environmental Protection Agency (EPA)|
|MOLINA, M - Environmental Protection Agency (EPA)|
|SIDLE, R - Environmental Protection Agency (EPA)|
|SULLIVAN, K - Environmental Protection Agency (EPA)|
|Meinersmann, Richard - Rick|
Submitted to: American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: 9/5/2013
Publication Date: 12/9/2013
Citation: Bradshaw, J.K., Molina, M., Sidle, R.C., Sullivan, K., Oakley, B., Berrang, M.E., Meinersmann, R.J. 2013. The relationship between land management, fecal indicator bacteria, and the occurrence of Campylobacter and Listeria spp. in water and sediments during synoptic sampling in the S. Fork Broad River Watershed, N.E. Georgia.. American Geophysical Union. December 9-13, 2014. San Francisco, California.
Technical Abstract: Fecal indicator bacteria (FIB) and pathogens stored in the bed sediments of streams and rivers may be mobilized into the water column affecting overall water quality. Furthermore, land management may play an important role in the concentrations of FIB and the occurrence of pathogens in stream water and sediments. The purpose of this study was to determine the relationship between FIB and pathogens in stream water and sediment based on three land management-affected categories: agricultural, forest, and waters receiving treated municipal wastewater. Two synoptic sampling events were conducted under baseflow conditions (<0.64 cm of rain within 24h) between October-November, 2012 and May-June, 2013. Counts of the E. coli and E. faecalis and occurrences of the enteric pathogens Campylobacter and Listeria spp. were measured in stream water and sediment samples collected at 15 locations (six agricultural (AG); six forested (FORS); and three receiving discharge from water pollution control plants (WPCP)) in the S. Fork Broad River watershed located in northeast Georgia, USA. Mean E. coli and E. faecalis concentrations were highest in the AG stream water samples (3.08 log MPN 100 mL-1 for E. coli and 3.07 log CFU 100 mL-1 for E. faecalis) and lowest in the FORS water samples for E. coli (2.37 log MPN 100 mL-1) and WPCP water samples for E. faecalis (2.53 log CFU 100 mL-1). E. coli concentrations (2.74 log MPN 100 mL-1) in the WPCP streams were intermediate. Similar to water samples, E. coli concentrations were highest in the AG sediments (4.31 log MPN g-1), intermediate in the WPCP sediments (4.06 log MPN g-1), and lowest in the FORS sediments (3.46 log MPN g-1). In contrast to E. coli, E. faecalis concentrations were lower (1.10 to 1.31 log CFU g-1) and relatively more constant than E. coli in sediments over the three land management categories. Campylobacter was detected in 27% of the water samples and 8% of the sediment samples. The highest occurrence of Campylobacter detection was in the AG streams (15% of the water samples; 5% of the sediment samples). Listeria was detected in 76% of the water samples and 65% of the sediment samples. The FORS and AG streams had the highest occurrence of Listeria in water and sediment (32% and 29% of the water samples, respectively; 24% and 29% of sediment samples, respectively) suggesting Listeria is fairly ubiquitous in these streams. Based on the high concentrations of E. faecalis in water and E. coli in water and sediment, and higher frequency of Campylobacter detection in the AG streams, this study indicates that E. coli and Campylobacter may occur in high concentrations in stream sediments in land management areas where fecal material is deposited directly by livestock into the stream or adjacent land in large doses.