Pollution level assessment of dam water used for domestic activities, in builpela of the tamale metropolis, Ghana

In the Northern parts of Ghana, highly turbid rainwater runoff and intermittent streams are collected in earthen dams. These dams serve as main source of drinking and domestic water for many communities despite their physical and microbial contamination. This study was conducted at Builpela in the Tamale Metropolis of Ghana to analyse the levels of chemical properties in the dam water used by the people in the area. Eight water samples were collected in May 2012 for the analysis. Atomic Absorption Spectrophotometer (AAS,) Flame photometer, Turbidimeter amongst others were used for laboratory analyses. The mean concentration of the parameters analysed were; 624.1 µS/cm for Electrical Conductivity (EC), 8.72 for pH, 57.3 mg/l for Chloride (Cl-) 50.1 mg/l for Potassium (K+), 260.2 for Bicarbonate (CHO3-),16 mg/l for Magnesium (Mg+), and 75 mg/l for Sulphide (SO4-). Apart from the mean Arsenic (As) concentration level of 0.0152 mg/l, all the heavy metals (Lead, Cadmium, Mercury) analysed were found to be absent in the dam water. Comparatively, most of the parameters were found to be within the WHO and Ghana EPA limits. pH, CHO3, K+ and As were however high in concentration. ANOVA on the concentration of these chemicals at the various banks of the dam realised significant difference for EC, pH and CHO3- with F probability (Fpr <0.05) of 0.005, 0.008 and 0.012 respectively. Even though pollution of the water was observed, concentrations were not alarming. The protection of the catchment and upstream activities which result in pollution of the reservoir should be controlled.