Aquifer characterization and groundwater flow dynamics in the upper left bank of Jemma River catchment, Blue Nile Basin, Ethiopia

Abstract

The complex nature of the Ethiopian aquifer requires detail, characterization, and analysis. Consequently, characterization of groundwater flow and major aquifer systems was conducted in the upper left bank of the Jemma River catchment in the Blue Nile Basin. The research area covered 1255 km2. The main objective of the research was to characterize the aquifer systems and groundwater flow dynamics of the area. The software applied during the research work were aquifer test, ArcMap 10.2, global mapper 17, AutoCAD, Exelis ENVI, geomatics, and rockworks. Pumping test data and spring discharge together with qualitative field description were used to classify the aquifer system. Accordingly, the different aquifer classes are fissured aquifer developed on basalts on the plateau (moderate to low groundwater potential), mixed aquifer (high permeability and very high productivity), fissured aquifer developed on basalts in the valleys (high permeability and low to moderate storage), porous and fissured sandstone aquifer in deep valleys, and localized aquifer with intergranular porosity and permeability (high permeability and high productivity). From the analysis of water level measurements of boreholes, hand-dug wells, and springs, the groundwater flow system is controlled by surface morphology and lineaments. Therefore, the groundwater flows from SE and S-SSE corner towards the N and NW corner of the catchment. Understanding groundwater dynamics and characterizing the aquifer in the catchment are very crucial which in turn help to manage the available water resource for domestic, industrial, and agricultural purpose. Besides, the research will be used to manage aquifers from depletion.