Geospatial Based Optimum Site Selection for Wastewater Treatment Plant: The Case of Debre Berhan Town, Amhara Regional State, Ethiopia

Wastewater treatment plant is one of the most serious problems the world facing, the problem gets more serious in developing countries. The city of Debre Berhan is currently generating wastewater simply discharging on the road, open fields and waterway sites that has not been selected by scientific study which is environmentally sound and socio-economically acceptable. Hence, it is found necessary to study and select new wastewater treatment plant site for the city that is environmentally, socially acceptable and economically feasible. This study was conducted by using Geographic Information System technique for selecting suitable wastewater treatment plant sites. Factors such as slope, elevation (altitude), proximity from ground water table, depth of ground water well, soil types, wind direction, geological types, land use/ land cover, proximity from roads and proximity from water bodies were used for selecting suitable wastewater treatment plant within the study area. The factor maps were reclassified and standardized in ArcGIS environment followed by preparation of their suitability maps. The weighted overlay analyses of the final map with final weighted factor map were integrated and produced the final suitable wastewater treatment plant site map using ArcGIS Spatial Analyst tools. As a result, 0.41km2 (0.72%), 10.24km2 (18.09%), 22.21km2 (47.91%), 18.35km2 (32.37%) and 0.9km2 (0.91%) of the total study area was found to be very highly suitable, highly suitable, moderately suitable, lowly suitable and unsuitable for wastewater treatment plant siting, respectively. The area of very high suitable are preferable for wastewater treatment plant sites, because of their minimum effect on environment, public health and cost effective than other parts of the study area. Therefore, the study will help the concerned authorities to formulate their development strategies according to the selected suitable wastewater treatment plant site available to the area