Bacteriological assessment of Spoon River water quality

Data from a study of five stations on the Spoon River, Ill., during June 1971 through May 1973 were analyzed for compliance with Illinois Pollution Control Board's water quality standards of a geometric mean limitation of 200 fecal coliforms per 100 ml. This bacterial limit was achieved about 20% of the time during June 1971 through May 1972, and was never achieved during June 1972 through May 1973. Ratios of fecal coliform to total coliform are presented. By using fecal coliform-to-fecal streptococcus ratios to sort out fecal pollution origins, it was evident that a concern must be expressed not only for municipal wastewater effluents to the receiving stream, but also for nonpoint sources of pollution in assessing the bacterial quality of a stream.