Building climate-resilience into basin water management

Project summary

Anthropogenic activities including illegal and uncontrolled mining and logging have seriously degraded the landscapes of many river basins in West Africa posing significant challenges to sustainable water resources management (WRM). Climate change (CC) is projected to impose additional stress on the water resources of these basins. The Pra (23,200 km2, 6.2 million people) and Densu (2,600 km2, 2.5 million people) are 2 river basins of high economic importance to Ghana that also face the above problems. They are the main sources of domestic water supply for major cities such as Koforidua (1.7 million people) and Accra (40% of a population of 3.2 million) and contribute substantially to the livelihoods of basin dwellers via irrigated agriculture and bottled water production. Both basins have existing WRM plans but new ones are required soon. These can benefit from a more robust climate change impact analysis using the newest IPCC scenarios. Existing impact studies on West African basins have not focused on a fully integrated analysis of the consequences of CC, LULC changes, and changes in the socio-economic and political developments.

This study proposes an interdisciplinary and cross disciplinary approach that considers WRM in two key river basins in Ghana in an integrated manner. The systems approach integrates CC, Shared Socio-economic Pathways (SSPs) and LULC change scenarios, water supply sources, quantities and quality, and competing demands (industrial, irrigation, livestock, municipal, ecosystems etc.) with analysis of current and projected future water uses, water infrastructure portfolios, existing natural water infrastructure in the basins, indigenous knowledge in WRM and water governance in the impact analysis. The generated trade-offs in WRM decisions and the developed stakeholder framework for basin WRM ensures that the study approach also supports and facilitates the much desired stakeholder engagement in sustainable WRM in river basins.

Outputs

Midterm report
Over the past 3 years, the project has made significant progress in all the key research areas of climate, hydrology, ecosystem valuation, water system optimization and water governance. Comprehensive literature reviews on water governance, groundwater resources and ecosystem valuation methods among others were completed; two of which were published in Journal of Hydrology - Regional Studies, and Water Policy. The project has significantly improved existing monitoring networks of climate, streamflow and groundwater in the Pra and Densu Basins through installation and monitoring of 60 weather stations, 22 groundwater wells, and 12 river gauged stations. Large proportion of data required for analysis and setting up simulation models have been collected and quality-controlled, and an article published in the Hydrological Sciences Journal. The project has setup an ensemble of hydrological, groundwater and water allocation simulation models and is in the process of adapting them to the project basins through extensive calibration processes. Narratives of SSPs for development in Ghana and the two project basins have been developed and are undergoing validation. The PhD students on the project have completed mandatory university coursework and are conducting their research. Covid-19 caused delays to implementation of some activities including joint research activities and stakeholder trainings. Hopefully, these activities will be covered in the remaining period of the project.