Toward an improved decision-making framework for two of Africa’s transboundary basins
By Patience Mukuyu, Researcher, IWMI-South Africa
Africa’s Omo-Turkana and Zambezi River Basins, like other transboundary systems across the developing world, pose a complex dilemma for stakeholders in the management of water and land resources. How to boost regional growth in the basins through hydropower development and irrigation, while also addressing concerns about the impacts of infrastructure development on ecosystem services and the local communities whose livelihoods depend on these?
To help create a better understanding of the impacts of particular development pathways in the two basins, ETH Zurich is leading a team of researchers from various African and European organizations, including the International Water Management Institute (IWMI), in the development of a decision-analytic framework to explore the water-energy-food nexus. Ongoing stakeholder engagement is a key feature of the framework, which is a central focus of the DAFNE project, funded by the Horizon 2020 Programme of the European Union.
Since the project’s launch in 2016, researchers have contributed important insights and solutions. In the Omo-Turkana Basin, for example, they have shown how increases in the human and livestock populations, together with changes in hydrology and land use, have intensified competition over pasture and water rights. At the same time, hydropower generation and irrigation schemes have reduced flows in the Omo River, affecting aquatic ecosystems and floodplain agriculture. These developments underline the need for an integrated basin-wide management approach, aimed at maintaining ecosystem services for generations to come. These include provisioning services, such as food and fuel, as well as regulatory functions related to the climate, water quality, flood control and soil retention.
In the Zambezi Basin – which harbors wetlands and lakes, and is rich in biodiversity – the DAFNE team is examining options to combat water hyacinth, an invasive floating plant species originally from South America. Water hyacinth seriously compromises ecosystem services, particularly the fishing and food production on which local communities depend, while also lowering water quality. The problem is especially acute along the Kafue River, one of the biggest tributaries of the Zambezi. Drainage from mining, industrial and urban areas releases nutrient-rich effluent into the river, causing water hyacinth to proliferate. Manual and biological control have so far proved ineffective. Using water hyacinth as an indicator of change in nutrients and flows, project researchers have concluded that increased “environmental” releases from the Kafue Dam may succeed in ridding the river system of the plant, which tends to predominate in stagnant, nutrient-rich, slow-flowing waters.
The DAFNE Project is also investigating ways to reduce the high incidence of malaria on the shores of the reservoir created by the Kariba Dam in the Zambezi Basin. Previous research has established a clear link between this infrastructure, which is critical for hydropower generation, and disease spread. Research results suggest that regulating water levels through dam releases may help solve the problem by making “hotspots” of malaria incidence along the reservoir shoreline less suitable for breeding of the mosquito vector.
During 2019, DAFNE will further strengthen its decision-support system for assessing development options. For this purpose, project researchers will conduct negotiation simulation laboratories (NSLs) in the two basins, bringing together stakeholders to test and provide feedback on prototypes of DAFNE’s multi-perspective visual analysis tool and geoportal. The latter will include a data catalogue, interactive maps and dynamic charts. The events will also provide a space for evidence-based engagement and discussions on water-energy-food issues. The series of NSL events will culminate in “mock” negotiation workshops, taking place in 2020. By simulating the negotiation of issues around management of the water-energy-food nexus, using data from the basins, stakeholders will develop the critical thinking and skills they will need to tackle real-life basin-wide challenges.
