Evaluation of Groundwater Potential Using Aquifer Characteristics in Urambo District, Tabora Region, Tanzania

Abstract

In developing countries like Tanzania, groundwater studies are essential for water resource planning, development, and management. Limited hydrogeological information on groundwater occurrence, availability, and distribution in Urambo District is termed a key factor that hinders groundwater development. This research was aimed at the evaluation of groundwater potential zones in a granitic gneiss aquifer in Urambo District by integrating six indicators (transmissivity, specific capacity, static water level, yield, total dissolved solids, and geology) that were developed and applied in the study area. The indicators were further combined, and a groundwater potential index map (GWPIM) was prepared using relative weights derived from the analytical hierarchy process (AHP). The results show that 67% and 27% of the study area are categorized as moderate and high groundwater potential zones, respectively. Groundwater is controlled by both Quaternary sediments (sands and gravels) and weathered to fractured granitic gneiss. Quaternary sediments host the major shallow aquifers (<35 m) with relatively high transmissivity, specific capacity, and yield (1.5 m2/day, 16.36 m2/day, and 108 m3/day, respectively). Granitic gneiss is not strongly fractured/weathered and forms an aquifer with a relatively low yield of about 10.08 m3/day. The findings were validated using three boreholes, and the results are consistent with the developed GWPIM. Such findings are of great importance in groundwater development as the techniques applied can be extended to other areas in Tanzania as well as other countries that experience similar geological environments.