Assessment of Spatial Variability of Groundwater Potential using Remote Sensing and GIS-based-Criteria Evaluation for Dar es Salaam, Tanzania

Abstract

Groundwater is an important resource for the continuous provision of water supply in both urban and rural areas. Lack of enough knowledge about the spatial variability of groundwater potential zones (GWPZS) has a negative impact on groundwater extraction development and management and may result into over exploitation. In this study, analytic hierarchy approach (AHP)-coupled with multi criteria decision analysis (MCDA) and GIS techniques were employed to integrate hydrogeological, geological as well as topographical data to assess spatial variability of groundwater potential zones of Dar es Salaam city. Seven thematic layers such as lithology, slope, land-use, lineament, drainage, soil, and rainfall were processed in ArcGIS and assigned appropriate weightage and theme classes ranks using Saatys AHP. The rasterized and reclassified thematic layers was integrated using weight overlay to generate the overall groundwater potential map.