What factors lead to high fecal indicator bacteria numbers in recreational waters?
The sources of fecal indicator bacteria include waste waters from sewage treatment plants; other types of sewage inputs such as combined sewer outfalls and drainage from septic tanks; runoff from agricultural fields or feedlots; effluents from food processing plants (especially meats and beverages); and stormwater runoff (which carries animal and bird droppings). The likelihood that fecal indicator bacteria added to the environment by these means will survive to be counted at a given water quality monitoring site is a function of the distance of the site from such sources, and also a function of the effect of all the environmental factors that influence bacterial survival. An early study (Burm, R.J. and R.D. Vaughan, 1966, Journal of the Water Pollution Control Federation, Vol. 38, pp. 400-409) compared the bacteriological quality of the separate stormwater distribution of the city of Ann Arbor, MI with that of the combined sewer system (specifically Conner Creek drain) of Detroit. Sam
