This dataset contains the input data and settings needed to run a Community Water Model (CWatM) of the Ebro River basin in Spain. The input data include: an elevation model of the catchment, flow direction map, river routing, lakes and reservoirs, soils, groundwater, land cover, crop coefficients population and GDP, and water demands for irrigation, livestock, industry, and domestic sectors. CWatM is a distributed hydrological model simulating the water cycle at global and local levels maintained by IIASA BNR Water Security group. The model was used to assess water supply and demand, and environmental needs, including water management and human influence within the water cycle in the Ebro River basin.