Application of National Sanitation Foundation and Weighted Arithmetic Water Quality Indices for the Assessment of Kaani and Kpean Rivers in Nigeria

Rivers present a continuous renewable physical resource for domestic and agricultural purposes. Kaani and Kpean rivers in Bori town in Rivers state, Nigeria are the common sources of water to the people. The water quality assessment of these rivers is carried out using fifteen physicochemical parameters. These parameters were measured for three consecutive months of July, August and September 2017 at three sampling points for each river. These months are the months of the rainy season. The samples were analysed using the standardized method of the American Public Health Association (APHA). The concentrations of all the analysed parameters were compared to World Health Organization (WHO) guidelines for drinking water. National Sanitation Foundation Water Quality Index (NSF WQI) and Weighted Arithmetic Water Quality Index (WA WQI) were used for assessment. The NSF WQI values of 59.77 and 63.45 were obtained for Kaani and Kpean respectively. The NSF WQI was able to give a good evaluation of the gradual change in the water quality of these two rivers as they flowed through the communities from Kaani to Kpean. The results obtained using the WA WQI gave values of 1.68 and 6.04 for Kaani and Kpean respectively indicating that these water bodies have excellent water quality rating and both methods find useful application in the assessment of Kaani and Kpean and rivers. This study shows that in the months of the rainy season, these two rivers have good water quality and are fit for use