APPLICATION OF WATER QUALITY INDEX IN THE DRINKING WATER QUALITY ASSESSMENT OF A SOUTHEASTERN NIGERIA RIVER

The physico-chemical parameters of Ikwu River were studied between January and June 2016 in 3 stations to assess its drinking water quality using water quality index. Weighted arithmetic water quality index (WAWQI) method was used. Thirteen parameters were evaluated which included temperature, pH, electrical conductivity (EC), dissolved oxygen, total dissolved solid (TDS), chemical oxygen demand (COD), nitrate, alkalinity, phosphate, sulphate, chloride and calcium. The physico-chemical parameters recorded were within acceptable limits except dissolved oxygen and pH. One-way analysis of variance (ANOVA) showed that pH, EC, TDS, COD and Calcium were significantly different and station 2 was observed to be the source. The Water Quality Index (WQI) for stations 1 and 3 were 56.49 and 57.21 respectively; categorised as poor drinking water quality while station 2 was 79.70; categorised as very poor drinking water quality. This study also showed that pH and dissolved oxygen were the contributing parameters that rendered Ikwu River unfit for drinking. It was concluded that water of Ikwu River is unsuitable for human consumption.