Spatial and SocioEconomic Impacts Analysis of BUI Hydropower Dam on Downstream Communities

Abstract

The construction of hydropower dams is seen by many countries as developmental projects aimed at improving economic opportunities. However, global issues on environmental awareness have increased attention on the impacts of dams on communities, and as such fresh attention to the downstream dam impacts is overdue and urgently needed. Against this background, hydropower dam projects are gradually seen emerging in Ghana as by their contribution constitutes a key source of energy for the country. The Bui dam, however, was commissioned and fully operational since early 2013 on the Black Volta Basin at the Bui Gorge. The prime objective of this study adopts an integrated approach of remotely sensed data techniques with socioeconomic data in examining the spatial and socioeconomic impacts of Bui dam on downstream communities. Satellite imageries of Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and Landsat 8 Operational Land Imager (OLI) were used to evaluate the Land Use Land Cover (LULC) dynamics for the periods 2001, 2008, and 2017 over the study area. Five (5) LULC types were delineated from the classified output maps, viz Forest deciduous, Pasturelands, Bare land, Waterbodies, and Farmlands & Settlements. The results of the LULC dynamics from 2001 to 2017 show that there is a continuous and fast pace depletion of Forest deciduous, Bare lands, and Pasturelands LULC types at a rate of 0.60%/year, 0.50%/year, and 1.84%/year, respectively. On the other hand, increasing rates are observed for Farmlands & Settlements, and Waterbodies land use types at a rate of 4.81%/year and 2.21%/year, respectively, over the same observation periods. The overall accuracies are 93.45, 74.47, and 72.84% for 2017, 2008, and 2001 observation periods, respectively. The spatial area and dimension of reservoir formed is approximately 366.95 km at a spatial elevation of 176 m. Also, informal information solicited from questionnaires were conducted. The results showed that Bui dam has both positive and negative impacts in the area and tends to be selective both spatially and socially. However, based on the views of the respondents and field observations suggest that the adverse effects of the dam are far more common and usually outweigh the benefits to the downstream inhabitants. Socioeconomic lives of the people have worsened than when the dam was newly constructed. Feasible suggestions, however, have been spelt out from the research that could substantially alleviate these impacts.