Bacteriological quality of drinking tap water in selected districts of north showa zone, Amhara, Ethiopia

摘要

The importance of good drinking water in maintaining health was recognized early in human history. People can survive days, weeks or months without food, but only about four days without water. But water remains the major source of transmission of enteric pathogens. A cross-sectional study conducted on drinking tap water quality from December to February 2015 at selected districts of north showa zone, to isolate indicator microorganism of water quality and to analyze the physiochemical parameters of water samples. A total of 15 tap water samples collected from three districts (Ataye, Shewarobit and Alem town) & transported to Debre Berhan University Biology department laboratory for bacteriological analysis. Of 15 water samples from public drinking water sources, 3(20%) samples were found negative (0) for total coliform whereas the remaining 12(80%) had coliforms ranging from 2 to 900/100ml of water. Analysis of physicochemical parameters temperature revealed that of the fifteen water sample 11(73.33%) had greater than 20oC while the remaining 4(26.66%) had a temperature of between 15-20 oC. Nine (60%) of the sample had pH range 6.5-8 on the other hand six (40%) of drinking water samples had pH less than 6.5. Analysis of total dissolved solids (Tds) showed that 8(53.33%) of water samples had Tds greater than 500 (mg/l) and 7(46.66%) comprises of less than 500(mg/l). Most of the investigated water samples had coliform count beyond the WHO standard. Regular quality control mechanisms need to be in place to ensure safety of drinking water.