Child mortality is a critical indicator of societal health, largely driven by unsafe water, poor sanitation, and stagnant water, which spread infectious diseases. While the links between water, sanitation, and hygiene (WASH) are well-documented, the specific role of water governance in human health is under-explored. Existing research often focuses on legal frameworks, limiting practical progress in sustainable freshwater management. The YAKU project addresses this gap by investigating how community water governance affects the health of children under five in the Andean and Maghreb regions. Using a transdisciplinary approach, it examines four governance aspects—legal, managerial, participatory, and intergovernmental—to support the child mortality targets of the Millennium and Sustainable Development Goals.