Watershed management, groundwater recharge and drought resilience: An integrated approach to adapt to rainfall variability in northern Ethiopia

Abstract

Rainfall variability coupled with poor land and water management is contributing to food insecurity in many sub-Saharan African countries such as Ethiopia. To address such challenges, various efforts have been implemented in Ethiopia. The objective of this study was to evaluate the long-term impacts of different soil and water conservation and water harvesting interventions on groundwater and drought resilience of the Gule watershed, northern Ethiopia. The study involved: (i) documentation of the approaches followed and the technologies implemented in Gule since the 1990s, (ii) monitoring the hydrological effects of the interventions for ten years, and (iii) evaluation of the effects of the interventions on groundwater (level and quality), spring discharge and suspended sediment concentration (SSC) in runoff. Results showed that interventions were implemented at different stages and scales. As a result of the interventions, the watershed was transformed into a landscape resilient to rainfall variability: (a) dry shallow groundwater wells have become productive and the level of water in wells has raised, (b) the groundwater quality has improved, (c) SSC in high floods has reduced by up to 65%, (d) discharge of existing springs has increased by up to 73% and new springs have started to emerge. Due to improved water availability, irrigated land has increased from less than 3.5 ha before 2002 to 166 ha in 2019. Communities have remained water-secure during an extreme drought in 2015/2016. Implementation of watershed management practices has transformed the landscape to be resilient to rainfall variability in a semi-arid environment: a lesson for adaptation to climate variability and change in similar environments.