Assessing the Effect of Land/Use Land Cover and Climate Change on Water Yield and Groundwater Recharge in East African Rift Valley using Integrated Model

•Integrated model was used to assess water yield and groundwater recharge (WYGR).•Effects of land use and climate change on WYGR were assessed.•Average annual precipitation and temperature are projected to rise.•Compared with the dry, the climate change effect in the wet seasons is substantial.•Land-use change reduces recharge while increasing groundwater discharge to the river. East African Rift Valley basin. Water availability in the rift valley relies heavily on the discharge from the highlands to rivers that run to the rift floor. This research explores the effect of Land use/Land cover (LULC) and climate change on water yield and groundwater recharge (WYGR) using coupled SWAT-MODFLOW, which integrates Soil and Water Assessment Tool (SWAT) and Newton Modular Finite Difference Groundwater Flow (MODFLOW-NWT). The LULC change was analyzed using artificial neural network-based cellular automata. The dominant LULC is cultivated land and expanded by 5% to the forest and grassland areas. The average temperature and precipitation are expected to rise by 8–11% and 3–6%, respectively. Climate change affects the spatiotemporal distribution of WYGR significantly, while LULC change has a trivial effect. Under the baseline scenario, the recharge was 10% of the average annual precipitation, but climate change is projected to reduce it by 47–53%. Water yield reduction up to 48% and change of perennial rivers to intermittent are expected in the coming decades. The region will experience water scarcity, emerging mainly from climate change.