Stakeholder-Informed Socioeconomic Scenarios for Water Use Projections: A Novel Approach to Assessing Climate Change Impacts in the Sudano-Sahelian Region

Water security in the Global South is increasingly threatened by rapid socioeconomic changes, including urbanization, population growth, and the expansion of irrigated agriculture. These dynamics not only intensify competition for limited water resources but also amplify vulnerability to climate change impacts. The Sudano-Sahelian region, including the Sokoto Rima Basin (study area) in Nigeria, is particularly sensitive to these pressures, having experienced severe droughts in the 1970s and 1980s. This study adopts a participatory approach, leveraging stakeholder input to develop socioeconomic scenarios within the Shared Socioeconomic Pathways (SSPs) 4.5 and 8.5 frameworks. It projects future water use in the region and evaluates the combined effects of socioeconomic and climate change. While the CMIP6 GCMs agree on a wetter future climate for the region, uncertainty persists regarding the magnitude of these changes. Drivers of socioeconomic changes are better understood due to direct stakeholders involvement. Key findings indicate that by 2050, irrigated land, and population are expected to increase by 470%, and 200% respectively, relative to the reference period (1990–2004). This growth is projected to drive water demand up by 190%, outpacing the anticipated 160% increase in water availability due to climate-driven changes. The results underscore that socioeconomic changes pose a significant risk to water security and must be considered when planning climate change adaptation. Informed by stakeholder feedback, the study highlights adaptation strategies, including the adoption of water-efficient technologies, mechanized irrigation, and advanced seed technologies. Small-scale stormwater harvesting through dam construction is proposed as a viable strategy to conserve water and support municipal supplies during drought periods. This novel participatory based scenario development approach provides valuable insights into managing water resources under concurrent socioeconomic and climate challenges, with implications for policy and planning in water-scarce regions.