Water Quality Assessment of Lower Usuma Dam Water from Treatment plant to points of Consumption in Federal Capital Territory, Nigeria

Abstract

This study investigated and compared the bacteriological, physicochemical and heavy metals concentrations of drinking water quality of Lower Usuma Dam from treatment plant to the points of consumption in three Area Councils (Bwari, Abuja Municipal and Gwagwalada) of the Federal Capital Territory, Abuja, Nigeria. Most probable number technique was employed for coliform detection. Molecular characterization of isolated bacteria was carried out. Seven out of the 26 water samples analyzed in this study were contaminated in the range of 7 MPN/100ml to >23 MPN/100ml. Physicochemical parameters such as colour, pH, temperature, turbidity, total dissolved solids (TDS), total hardness, electrical conductivity, total alkalinity and seven heavy metals were also determined using Atomic absorption spectrophotometry. Results showed that Bwari had the highest value for colour, 16.67 Pt.Co while AMAC had the least with 1.00 Pt. Co, Gwagwalada had the highest pH value (7.33±0.12) and Bwari the lowest pH of 6.77±0.06. Bwari also had highest temperature of 30.23±2.80oC while AMAC recorded the least (27.29±0.26oC). Turbidity ranged from 1.86 to 2.83 NTU. The highest level of the other parameters [(TDS 54.27 mg/L, conductivity 90.10 µs/cm, total hardness 34.00 mg/L, total alkalinity 28.00 mg/L, Cl– 20.82 mg/L)] was observed in water samples from Gwagwalada Area Council. Gwagwalada recorded the highest values for iron and zinc at 0.09mg/l and 0.003mg/l respectively. Copper concentration was highest in AMAC (0.043mg/l) and lowest in Bwari area council (0.007mg/l). There was no significant difference (p>0.05) in the concentration of Cr detected in all the water samples. There is need for provision of adequate sanitation facilities and improvement on monitoring of distribution system in order to maintain drinking water quality and prevent water borne disease outbreaks.