Seasonal Variations of Fecal Indicator Bacteria in Surface Water.

The detection of microorganisms in water is one of the basic concerns of public health.  Microbiological impairment of water is assessed by monitoring concentrations of total coliforms, E.  coli, and Enterococci.  Total coliform bacteria are commonly found in the environment (e.g., soil or vegetation) and are generally harmless.  However, the presence of E. coli and Enterococci, both found in the fecal excrement of humans, livestock and wildlife may pose human health risks.  This study compares the presence, absence and abundance of the three indicator bacteria from three surface water sources (Big Spring Park, Brahan Spring Park, and Ditto Landing) located in Madison, County, AL.  The analysis was performed using the IDEXX colilert (total coliform, E.coli) and enterolert (enterococci) tests. Results confirmed the presence and of all three indicator bacteria and revealed seasonal variations in the quantity of the bacteria in the in the water samples.  However, one of the samples, Big Spring Park, which is highly populated with ducks, had the highest level of total coliform, E. coli, and enterococci for all seasons.  Future studies will utilize microbial source tracking techniques to determine the origin of contamination. Understanding the sources of fecal contamination is critical for assessing associated human health risks, for developing management plans to protect recreational waters, and for preserving the integrity of water supplies.