By Buyani Fakudze and Jonathan Lautze
The Incomati Basin spans Eswatini, Mozambique, and South Africa. With growing demand for water from the energy and agriculture sectors, as well as increasing threats posed by climate change, the need for effective and integrated transboundary resource management is greater than ever.
In 2023, a comprehensive river basin systems model was developed to address issues around data availability and serve as a decision support system (DSS) to support water allocation reform in the Incomati Basin. The DSS uses an open-source Python Water Resources (Pywr) framework to simulate multiple scenarios, and account for the water resource implications of water demands from the agriculture, domestic, industry, and energy sectors.
The model was designed under the CGIAR Initiative on NEXUS Gains, by researchers from the International Water Management Institute (IWMI) in partnership with the Incomati and Maputo Watercourse Commission (INMACOM) and the University of Manchester. Work on the model has been ongoing since August 2022, with young professionals from all the INMACOM member states meeting monthly to contribute insights and hydrologic data.
Zanele Lulane is Projects Officer at the Joint River Basin Authority – Project Board and one of the participating young professionals. Having experienced how it works, she is enthusiastic about the model’s potential.
“As water resource professionals working across river basins in Eswatini, we’re constantly seeking innovative tools to optimize water resource management,” Ms Lulane said. “With in-depth exposure and training in the model, I have come to realize its potential as a valuable decision support system for enhancing water management in Eswatini. The model integrates diverse data sets, and this comprehensive understanding is crucial for developing sustainable water management strategies that will ensure equitable access and environmental protection for all riparian countries.”
Fostering engagement
In January 2024, IWMI and INMACOM hosted a three-day workshop in Mbombela, South Africa to share progress made under the Incomati Basin-wide model project. The workshop brought together a community of practice focused on modeling of the river water resources. Participants included the INMACOM secretariat, representatives of member states, developers, operators under INMACOM (Komati Basin Water Authority, Inkomati–Usuthu Catchment Management Agency, and Administração Regional de Águas do Sul), and the young professionals who contributed to the development of the model.
The workshop opened with an overview of Incomati allocations and deliberations from a November workshop implemented through the River and Environmental Management Cooperation, a transboundary stakeholder cooperation initiative in the basin. This was followed by refresher exercises on Pywr and Water Strategy, an online platform for collaborative water management that can be used to run and share the model. The young professionals then used available data to present the progress on the various scenarios modeled through Pywr.
One key outcome of implementing this activity has been the application of the model – in the context of the water sharing arrangements, namely the Interim IncoMaputo Agreement – to better understand the impact of different scenarios on water availability across key sectors and countries in the basin. These included scenarios such as more efficient irrigation and the decommissioning of thermal power stations.
The workshop also introduced the participants to Water Accounting, a platform that allows for the study of the current status and trends in water availability and usage at various points across the basin. This platform is a possible add-on to complement the models presented by Pywr.
Outcomes and a way forward
At inception, the NEXUS Gains’ primary aim was to develop a system that could add value to INMACOM. The perception among participants at the workshop is that there is value in Pywr as a tool for understanding different scenarios, even though there remain some areas requiring improvement.
Edward Mswane, Interim Executive Secretary of INMACOM, shared his thoughts on the advantages of the model, and how it can support his organization. “As a transboundary river basin organization, INMACOM has a mandate to ensure the sustainable and equitable sharing of the resources. Data availability plays a fundamental role in this, and the basin-wide model seeks to support this aspect of INMACOM’s mandate. There are several advantages to this model, such as the ability to explore various scenarios helps in guiding deliberations on issues like allocations. Another advantage is that it runs on Python, which significantly lowers the cost. As the development nears completion, INMACOM looks forward to having the platform as part of its decision support system, used within the secretariat offices as well as by the INMACOM operators.”
The next phase of the project is the handover to INMACOM. A plan of action is being developed between INMACOM and IWMI, outlining how this will be undertaken. The handover will include strengthening the capacity within the INMACOM secretariat to use the DSS, including the ability to address minor bugs. The optimum performance of the platform is dependent on the capacity of the operators to effectively use Pywr in their localized context, which implies a need to build capacity with them as well.
Further reading
- Learn more about the Pywr model in this NEXUS Gains webinar
- Read about NEXUS Gains’ work in the Incomati Basin.
Buyani Fakudze is a Data Manager at INMACOM; Jonathan Lautze is a Research Group Leader at IWMI.
This work was carried out under the CGIAR Initiative on NEXUS Gains, which is grateful for the support of CGIAR Trust Fund contributors: www.cgiar.org/funders
Header image: Participants at the three-day, Incomati Basin-wide model workshop in Mbombela, South Africa.
