[Quantitative studies of fecal indicators in various purification stages at two sewage purification plants in...

In two sewage treatment plants, situated in Kiel (Bülk) and Plön, Schleswig-Holstein, FRG, fecalcoliforms, totalcoliforms and enterococci were investigated as to quantity from October 1981 till November 1982. The number of the investigated bacteria varied widely during the whole investigation period. Showing the most distinct variations fecalcoliforms decreased in number, especially in December 1981 and January 1982. The majority of the samples yield bacterial numbers with the gradiation totalcoliforms greater than enterococci greater than fecalcoliforms. In the course of the purification process increasing variations of all bacterial parameters were found predominantly in the final settling tank. The possibility of influences induced by the input of catch pit's sludge is discussed.