Groundwater Resources in the Main Ethiopian Rift Valley: An Overview for a Sustainable Development

Abstract

In arid and semi-arid areas, human health and economic development depend on water availability, which can be greatly compromised by droughts. In some cases, the presence of natural contaminants may additionally reduce the availability of good quality water. This research analyzed the water resources and hydrochemical characteristics in a rural area of the central Main Ethiopian Rift Valley, particularly in the districts of Shashemene, Arsi Negelle, and Siraro. The study was developed using a census of the main water points (springs and wells) in the area and the sampling and physico-chemical analysis of the water, with particular regard to the fluoride concentration. In many cases, fluoride content exceeded the drinking water limits set by the World Health Organization, even in the absence of anthropogenic contamination. Two different aquifers were recognized: A shallow aquifer related to the eastern escarpment and highlands, and a deep aquifer in the lowland areas of the rift valley on the basis of compositional changes from Ca–Mg/HCO3 to Na–HCO3. The distribution of fluoride, as well as pH and EC values, showed a decrease from the center of the lowlands to the eastern highlands, with similar values closely aligned along an NNE/SSW trend. All these data contribute to creating awareness among and sharing information on the risks with rural communities and local governments to support the adequate use of the available water resources and to plan appropriate interventions to increase access to fresh water, aimed at the sustainable human and rural local development of the region.

Review: Groundwater research in the Ethiopian Rift Valley Lakes region

“…Understanding the paleoclimate, lake-level fluctuation, the geochemistry of sediments, isotope pattern of precipitation, fluid-rock interaction, lake-groundwater relationships, and understanding the hydrogeological system of the CRV were among the topics that attracted researchers (Baumann et al, 1975;Gasse and Street, 1978;Darling et al, 1996; Rozanski Ayenew, 1998). Water quality deterioration and degradation; and modeling and evaluation of the water resources are emerging research issues (Haji et al, 2018;Thomas et al, 2019;Abraham et al, 2021;Bonetto et al, 2021;Kebede et al, 2021;Ligate et al, 2021). The increasing need for the development of water resources initiated mapping projects at different scales, and the development of master plan studies (Chernet, 1982;Chernet et al, 1988;HALCROW, 1989;MoWR, 2009).…”

“…There are studies done to assess and evaluate the water resources in the CRV and the Rift Valley. Among these studies are: Comparative assessment of the water balance and hydrology of selected Ethiopian and Kenyan Rift Lakes (Ayenew and Becht, 2008) (Thomas et al, 2019); Analytical Hierarchal Process (AHP) based analysis of groundwater potential in the western escarpment of the Ethiopian rift valley (Abrar et al, 2021); Groundwater Resources in the Main Ethiopian Rift Valley: An Overview for a Sustainable Development (Bonetto et al, 2021); and Quantifying the Regional Water Balance of the Ethiopian Rift Valley Lake Basin Using an Uncertainty Estimation Framework (Abraham et al, 2021). However, there are significant differences in the figures they are providing, and in the approaches, they are following.…”

“…At present, water education and research activities are carried out by more than eight universities found across the country. Research topics like groundwater hydraulics, interactions between groundwater and rivers, lakes, and wetlands; land use and climate changes; pollution, trans basin flows (Alemayehu et al, 2018) and evaluation and modeling are on the rise (Ayenew, 2001(Ayenew, , 2002Tekle-Haimanot et al, 2006;Kebede et al, 2007Kebede et al, , 2008Belete et al, 2016;Bonetto et al, 2021).…”

Does the urban poor want water service improvement? Residents’ preferences for future water service supply in the Central Rift Valley of Ethiopia

“…However, it is quite important to investigate the value of a safe drinking water supply in the Rift Valley area with excess fluoride concentration. In addition to excess fluoride concentration due to the geological setting, there is also a scarcity of water resources available for the local communities which is one factor that causes a problem of reliable water supply to the community (Bonetto et al 2021). This problem requires enough resource generation to overcome the issues of improved water supply.…”

Investigation of Hydrochemical Dynamics of Groundwater in Coastal Blocks of Tiruvallur District, Tamilnadu, India

“…The disturbances due to anthropogenic activities and the action of natural processes like geological formation, dissolution of minerals, infiltration rate, recharge water quality leads to the deliverance of contaminants which inturn makes the groundwater vulnerable to contamination [5][6]. In developing countries', the outcome of increasing climate extremes like droughts and floods, socioeconomic and technological developments affect the usage and quality of water resources [7].…”