School of Earth Sciecne
Permanent URI for this communityhttps://repository.mu.edu.et/handle/123456789/202
Browse
1 results
Search Results
Item GROUNDWATER POTENTIAL EVALUATION USING AN INTEGRATED HYDROGEOLOGICAL APPROACH(Mekelle University, 2025-11-24) ATAKLTI GEBRETSADIKGroundwater is the main source of water for Abi-adi town and the people residing in its vicinity. The well field is found in Getskimlesley catchment located to the North of Abi-abi town. The potential of the well field was not estimated before and there is water exploitation each day. There is also high demand from different actors. So before creating social problems and damaging the aquifer due the excessive withdrawal, estimating the resource is mandatory. The study is to estimate the groundwater potential of the catchment; the amount of water that is recharging the groundwater, the runoff and the water that is evapotranspired annually, to estimate the potential & manage & protect accordingly. Water balance, pump test, geophysical and hydrogeological approaches employed to estimate the resource and to characterize the aquifer of the well field. The potential evapotranspiration is determined from the Penman-Monteith approach & its value is 2158.33mm per year. The actual evapotranspiration computed using Thornthwaite-Mather soil water balance method is 738.32mm per year. The value of runoff coefficient is 0.31 & this is affected by soil type, slope and vegetation of the study area. The amount of water that leaves the catchment as surface runoff & the water that merges to the groundwater system annually 363.88 & 71.60 mm/year respectively. The main lithological formations of the area are basement rocks and sandstone & the source of groundwater is relatively thick; medium to coarse grained and sorted Enticho sandstone & fractured basement rocks. There are a number of wells drilled in the basement rocks and sandstone formation in the catchment. The productivity of the wells ranges from dry well to 7 liters per second whereas the yield measured in the sandstone ranges from 5 – 30 liters per second. The average minimum & maximum Transmissivity of the aquifers which is calculated from the pump test data are 1.3 & 834.8 m2/day respectively. Then the catchment is categorized into three different zones of moderate, low and very low productivity. The maximum drilled depth in the sandstone formation is 194 meters and the thickness of this formation reaches 400 meters. The maximum depth drilled in the basement rocks is 120 meters. Groundwater Poteotential Evaluation of Getskimlesley Catchment, The main water type of the catchment is Ca-Mg-SO4-HCO3 & the quality is within the allowable limit of the standards for irrigation & domestic use. The amount of water that withdraws from this well field should be below the amount that is merging to groundwater.