Tag Archives: groundwater recharge

Groundwater Recharge Assessment using WetSpass and MODFLOW: Case of Hormat-Golina sub-basin, Northern Ethiopia (Published)

Water scarcity in northern Ethiopia, as well as its socio-economic relevance in terms of water demand for agriculture and domestic use, are at the root of the search for new groundwater resources and the development of groundwater models that can be used to control and manage the resource. WetSpass-MODFLOW was used to estimate groundwater recharge in the Hormat-Golina sub-basin. The purpose of this study was to determine the amount of groundwater recharge in the Hormat-Golina sub-basin. Following that, the MODFLOW groundwater flow simulation model is utilized to simulate the hydraulic head distribution. The Steady-state groundwater flow calibration was determined by comparing measured and simulated hydraulic heads. The mean annual evapotranspiration, surface runoff, and groundwater recharge, according to WetSpass result, were 516.6, 204.9, and 35.6 mm, respectively. Groundwater recharge accounted for 4.7% of precipitation, while actual evapotranspiration and surface runoff accounted for 27%t and 68% of precipitation, respectively. In such seasonal variations (summer, winter and annual), the groundwater head distribution is 9.37 to 29.86m in winter (dry season), 9.53 to 29.89 m in summer (wet season), and 9.58 to 30.17 m in Annual stress periods (recharges). For all stress periods, the estimated hydraulic heads in steady-state fit well with the measured ones, with a correlation coefficient of 0.86 (summer, winter and annual recharge). The balance between groundwater recharge and expected abstraction rates for agriculture and domestic water supply must be considered in future groundwater resource development plans in the valley to ensure the resource’s long-term sustainability.

Keywords: Ethiopia, MODFLOW, groundwater recharge, hormat-golina, wetspass

Assessment of Water Balance Components by Using Wetspass Model: The Case of Dengego Sub-basin, Eastern Ethiopia (Published)

The search for new water resources, as well as the development of water balance models that can be used to control and manage the resource, is at the heart of the search for new water resources in eastern Ethiopia, particularly in the Dengego sub-basin, and its socio-economic significance in terms of water demand for agriculture and domestic use. The water balance components of the Dengego sub-basin were investigated using the WetSpass hydrological model. The goal of this study is to assess the water balance components in the Dengego sub-basin. According to WetSpass, the mean annual evapotranspiration, surface runoff, and groundwater recharge were 494.2, 173.6, and 20.2 mm, respectively. Actual evapotranspiration and surface runoff accounted for 25.2 percent and 71.8 percent of precipitation, respectively and recharge made up 2.9 percent of precipitation. Annually 7.3 million m3 of water recharges into the groundwater table as recharge from the precipitation on the entire watershed.The contribution of this study could be used as baseline information for regional water resource experts, policy makers and researchers for further investigation. It can also be concluded that integrated WetSpass and GIS-based models are good indicators for estimating and understanding of water balance components in a given watershed to implement an integrated watershed management plan for sustainable utilization and sustainable development.

Keywords: Ethiopia, Water Balance, dengego, groundwater recharge, wetspass