Dam-induced Pollution in Ghana: Assessment of the Activities of Resettled Communities in the Vicinity of Bui Power Project on Freshwater Bodies

Abstract

Dam-induced pollution of freshwater bodies in sub-Saharan Africa has increased with its attendant resettlement challenges. The damming of the Black Volta in Ghana led to the resettlement of some inhabitants who lived close to the Black Volta. The study aims to investigate the impact of the Bui Power Project on the surface water quality of its resettlement communities, 5 years after the operation of the dam. The study employed standard operating protocols to assess selected physicochemical indicators of pollution in selected freshwater bodies in the study area over a 12 month period. Parameters analyzed included pH, conductivity, total dissolved solids, alkalinity, calcium, magnesium, BOD, COD, SO42−, DO, and total hardness. A membrane filtration technique was employed to enumerate total coliform, faecal coliform, and E. coli using Chromocult Coliform Agar. The result showed that pH levels did not differ significantly among the analyzed freshwater bodies. The Black Volta showed a large deviation from its baseline pH value (7.0). Agbelekame South and Bongaase Nsuano freshwater bodies recorded significantly high electrical conductivity (78.97 ± 2.758) and alkalinity (33.38 mg/L), respectively. TDS of the Black Volta was also significantly high (96.5 mg/L), however, it had a much lower value than its baseline (166.3 mg/L). Magnesium level in the Agblekame South was high (31.83 mg/L) followed by Gyama Nsuano (23.23 mg/L). The Black Volta also had elevated BOD (26.75 mg/L) and COD (71 mg/L) values. Faecal coliform from Agbelekame North and Agbelekame South (4.4 × 104 and 4.0 ×104 cfu/100mL, respectively) exceeded the GEPA/WHO acceptable guidelines for drinking water. Bongaase Nsuano and Gyama Nsuano recorded high total coliform count (9.1 cfu/ 100 mL and 15 cfu/100 mL, respectively) with values exceeding the recommended guidelines. Our study has provided evidence to show that adjoining surface water bodies around the Bui power project were microbiologically polluted due to the resettlement of communities around the Bui Dam environs.