A framework to assess cooperation benefits of new infrastructure in transboundary river basins without formal water sharing arrangements and operating rules

New dams can alter river flow regimes impacting downstream benefits and multi-sector services from water infrastructure and ecosystems. Impacts can be unpredictable in complex transboundary river basins that do not follow standardised operating rules nor have extensive historical data. In this case it is more difficult to assess the consequences of new infrastructure and provide a structured approach to achieve cooperative operating strategies to avoid transboundary water conflicts. This study presents a framework to evaluate the benefits of cooperation on managing new dams in transboundary multi-sector river basins that do not have formal cooperating strategies. A case study of the new Pwalugu Multipurpose Dam (PMD) located in Ghana’s Volta river basin is provided. The PMD could impact downstream riverine livelihood, ecosystem services, and water infrastructure like the downstream Aksomobo hydropower plant, the country's largest installed generation plant (1,020 MW). Also, the PDM could be impacted by future irritation developments of the Bagre Dam, an existing upstream dam managed in Burkina Faso. We show that a non-cooperative operation between the PMD and the Bagre dam in Burkina Faso could reduce inflows into the Akosombo dam, negatively impacting national hydropower generation. Also, a non-cooperative operation could decrease floods in Northern Ghana, impacting environmental services and local communities that depend on flood recession activities. We show that cooperative infrastructure management achieved by the proposed approach could offset possible negative impacts produced by the new PMD.