Climate change, extreme weather, and increasing water demands pose new challenges for the water industry and require innovative solutions. The Water Management Data Space provides a secure, federated framework for data exchange and collaboration. Among other things, it integrates IoT sensor data, geological models and historical data into a common platform. This enables early risk identification, optimized infrastructure operations, and data-driven investment planning. We explain the architectural and governance principles that create trust and interoperability and, using concrete practical examples, demonstrate how data can be turned into intelligent decisions – for a resilient and sustainable water industry.