Abstract

Water quality was assessed from 11 hand dug wells in the Adentan Municipality using Water Quality Index (WQI) and bacteriological load as indicators. The sampling was conducted during the months of July to September, 2019. A total of 33 samples were taken from 11 hand dug wells at monthly intervals. Weighted Average Water Quality Index (WAWQI) was used to compute parameters which include temperature, pH, conductivity, total dissolved solids, turbidity, total solids, biological oxygen demand, salinity and total alkalinity. Indicator fecal coliforms were also enumerated. All samples showed presence of E. coli and Salmonella in the dug wells with AD₂ having the highest E. coli count of 1.32x10³cfu/100 ml. AD₁₁ had the least count of both E. coli and Salmonella (1.28x10² cfu/100 ml and 1.68x10¹ cfu/100 ml) respectively. The highest WQI value was recorded for AD₇ and the lowest was recorded for AD₉. 36.4% of the wells were graded as “A” whilst the remaining 63.6% were graded “B”. The combined results of WQI and bacteriological assessment shown that the water quality determined only by WQI (physico-chemical) parameters cannot reflect the true water quality status.

Key words: Water quality index, bacteriology, weighted average water quality index, indicator.