Taye Alemayehu (PhD)Seyoum Bezabih2024-03-122024-03-122024-01https://etd.aau.edu.et/handle/123456789/2362Water is one of the most essential commodities for mankind and the largest available source of fresh water is obtained from groundwater. The Hormat-Golina sub-basin is one of the groundwater-based irrigation areas located in north wollo zone of Amhara region. Due to the erratic nature of rainfall (both time and space) distribution in the area, people often fail to maintain the soil moisture requirement for growing crops. Thus, the need for agricultural development using groundwater resources in the area is growing continuously. However, the ambitious plans for expanding irrigation have not been adequately strengthened through the assessments of groundwater reserves and groundwater recharge estimations. Understanding the spatial variability of groundwater recharge in response to distributed Land-use, soil texture, topography, groundwater level, and hydrometeorological parameters is significant when considering the safety of groundwater resource development. Thus, this study was aimed at estimating the spatial groundwater recharge of Hormat-Golina sub-basin, in northern Ethiopia using a spatially distributed water balance model (WetSpass). Input data for the model were prepared in the form of grid maps using a 30 m grid size and the parameter attribute tables were adjusted to represent the Hormat-Golina sub-basin condition using expert knowledge and scientific literature. The model result shows there was a good agreement between the observed and simulated surface runoff with R2=0.90 and NSE= 0.85. The results of the model indicated that the long-term temporal and spatial average annual rainfall of 828.5 mm was partitioned as 156.4 mm (19%) of surface runoff, 616.7 mm (73%) of evapotranspiration, and 55.4 mm (8%) of recharge. The recharge corresponds to 4.2*105 cubic meters (m3) for the Hormat-Golina sub-basin (with an area of about 698.25 km2) from which 83% of the recharge takes place during the rainy /wet/ summer/ season, while the remaining 17% takes place during the bega (dry) season. The highest recharge was observed in forest land with sandy soil. The analysis of the simulated result showed that WetSpass works well to simulate water balance components of the Hormat-Golina sub-basin and is especially suitable for studying the effects of Land-use changes on the water regime in the basin.en-USEstimationGroundwater RechargeHormat-Golina Sub-BasinThesis