Assessment of Water Quality Index in Densely Populated Areas of Jos Metropolis Central, Nigeria

Abstract

Water quality index refers to the quality of a given water sample represented by its index number that indicates the general water quality for various intended uses. The study aims to assess the water quality index in densely populated low-income areas of Jos metropolis. Thirty-three (33) water samples were collected from hand-dug wells (26 from high-population-density areas and 7 from low-population-density areas) using 100 mL sanitized water bottles. A BWB XP flame photometer was utilized to analyze the anions, a HACH DR1900 portable spectrophotometer was used to analyze major ions, while HCO3 - was determined by the titrimetric method. In the biological analysis, total coliform count, total plate count, and their isolates were determined by membrane filtration. The weighted arithmetic method was used for the computation of the water quality index. The chemical parameters in the area showed that Na+ > Mg2+ > K+ > Ca2+ for the cations and HCO3 - > Cl- > SO4 2- > NO3 - for the anions. Results obtained from the water quality index showed that 15.2% of the water samples were excellent, 24.2% were of good quality, 18.2% were of poor water quality, 15.2% were of very poor quality, while 27.2% were unsuitable for drinking. There is no variation for these water quality indices irrespective of the population density. The water quality index showed that 72% of the water is potable for drinking, whereas 28% is not potable. The presence of pathogenic and indicator organisms in most of the water samples may render it unfit for human consumption without proper treatment.