AQUIFER CHARACTERIZATION OF ARDI RIVER CATCHMENT UPPER BLUE NILE, ETHIOPIA

Zemen Minale

dc.contributor.author	Zemen Minale
dc.date.accessioned	2022-01-24T06:32:57Z
dc.date.available	2022-01-24T06:32:57Z
dc.date.issued	2022-01-24
dc.identifier.uri	http://ir.bdu.edu.et/handle/123456789/12947
dc.description.abstract	This study was carried out to characterize the different aquifer systems in Ardi river catchment, Upper Blue Nile Basin, Northwestern Ethiopia. The catchment is characterized by different volcanic and metamorphic rocks overlain by sediments. Currently, fast growing of population and water utilized activities increment, inadequate water from the wells (declining water level and discharge), some wells are being completely dried and no study has made on aquifer characterization in the catchment were the challenges and the initiative of the study. To minimize the challenge, an indirect evaluation of hydraulic properties using integrated geological, hydrogeological, hydrogeophysical and hydrometeorological methods have been launched to characterize aquifers and evaluate groundwater productivity. Though several methods are used to characterize the aquifers and identify the groundwater prospects of an area, Vertical Electrical Sounding and pump testing of boreholes were the key methods used to recognize hydraulic properties of the aquifer system.VES and Electrical Profiling are carried out to determine resistivity, thickness, depth, vertical lateral and variations of the geological formations which are used to obtain entire geological picture of the area. The study result revealed four to five main geoelectric layers that differ in degree of weathering and fracturing basalt. The highly weathered and fractured shows low resistivity with high aquifer thickness is the main water bearing horizon which has good groundwater potential, especially in the Southeastern and Northwestern part of the study area. An effort has made to estimate transmissivity, hydraulic conductivity, and the thickness of the aquifer system by establishing a relationship between the pumping test results and vertical electrical soundings. As a result, it is found that transmissivity varies from 2.1 to 132m2/d, hydraulic conductivity ranges from 0.05 to 3.84 m/d and aquifer thickness varies from 3-111m. Accordingly, the aquifer of the catchment was classified into aquitards, low productive fissured aquifer, low to moderate productive porous aquifers, moderate and high productive fissures aquifer.The mean annual groundwater recharge estimated by conventional water budget (504.7mm/year) and Soil Moisture Balance (552 mm/year) is 528.4 mm/year. The general groundwater flow direction was from Eastern towards Western part of the study area nearly similar to surface water flow direction. Generally, the western part of the study area around Mentawuha are mostly covered by crystalline basement rock which is an aquitard, therefore, site selection of groundwater investigation needs care full attention. In general, from geological, hydrogeological and geophysical investigation results, the high potentiality aquifers were found mainly on the Northern, Northeastern and in Southeastern parts of the study area.	en_US
dc.language.iso	en	en_US
dc.subject	hydrogeology	en_US
dc.title	AQUIFER CHARACTERIZATION OF ARDI RIVER CATCHMENT UPPER BLUE NILE, ETHIOPIA	en_US
dc.type	Thesis	en_US