Evaluating three simple methods to assess the microbial quality of drinking water in Indonesia

Abstract

AbstractThree simple microbial tests [H2S paper strip, lauryl tryptose broth + 4‐methyl‐umbelliferyl‐β‐d‐glucoronide (LTB + MUG), Colilert] were used to assess the microbial quality of water in the distribution system of Banjarmasin, the capital city of South Kalimantan Province (Borneo), Indonesia. Martapura River, the source of the drinking water, is contaminated with total coliform, Escherichia coli, and hydrogen sulfide producing bacteria. However, this water is treated and chlorinated to a residual of 1.0 mg/L before it is distributed to the city. No coliform or hydrogen sulfide producing bacteria were detected in the chlorinated water leaving the treatment plant. A total of 46 water samples were obtained from public taps at three subdistricts in the city located 2–8 km from the water treatment plant. Residual chlorine levels ranging from 0.0 to 0.8 mg/L were detected in the 46 drinking water samples. Of these, 47.8% was positive by the H2S test and the Colilert test. The LTB + MUG test was positive in 45.7% of these 46 water samples. Virtually all (96–100%) of the coliform positive samples contained E. coli. The H2S test appears to be a reliable, inexpensive, and especially suitable to assess the microbiological quality of drinking water in Indonesia.