PHYSICOCHEMICAL AND BACTERIOLOGICAL ANALYSES OF BOREHOLE WATERS IN ANINRI, AWGU AND OJI RIVER LOCAL GOVERNMENT AREAS OF ENUGU STATE, NIGERIA

ABSTRACT

Physicochemical and bacteriological analyses of borehole water samples were randomly collected from ten boreholes which supply drinking water to various communities of Aninri, Awgu and Oji River Local Government Areas of Enugu, Nigeria. The boreholes were sampled in both dry and rainy seasons. The following physicochemical parameters: pH, temperature, colour, electrical conductivity, turbidity, total dissolved solids, hardness, calcium, magnesium, sodium, potassium, alkalinity, acidity, lead, copper, cadmium and iron were determined using standard methods. E. coli count was determined by membrane lauryl sulphate broth method. Results of physicochemical tests were in compliance with WHO guideline values, except in the cases of sulphate level of 1,670 mg/L in water sample from Mpu in Aninri L.G.A., high chloride levels in samples from Ndeaboh and Mpu with values of 18,088 anrd 1,095 mg/L respectively. Similarly, sodium was also very high in the two boreholes, 5,625 and 8,500 mg/L. The water samples showed acid pH particularly in Oji River with values ranging from 4.30 to 6.30. Most of the water samples were soft waters, except samples from Ndeaboh, Mpu and Mgbowo with hardness values of 6,250, 6,250 and 840 mg/L respectively. Trace metal concentrations were below WHO guideline values, except samples from Mgbowo and Nnenwe with iron values of 4.54 and 3.13 mg/L. E. coli was isolated in two boreholes located in unkept surroundings in Oduma and Agbogugu with E. coli counts of 7 and 108 cfu/100 mL respectively. Generally, the borehole waters are considered safe for drinking except these ones polluted with E. coli and sodium chloride. The effects of unsafe drinking water are discussed, with recommendations to the Authorities regarding the safety measures to be applied.