A High‐Resolution Hydrological Dataset for Ukrainian River Basins With an Interactive Web Interface

ABSTRACT The ongoing and post‐war reconstruction of Ukrainian water resources is critical for food production, public health, energy, industry and environmental protection. This effort, the most ambitious in Europe since World War II, faces challenges due to a lack of accessible decision‐support tools for managing water ecosystems effectively. In response, we developed a high‐resolution hydrological model of the Ukrainian Watershed using the SWAT (Soil and Water Assessment Tool) model to assess water balance across all nine major river basins, covering an area of 873,600 km 2 . The model is integrated into an interactive web interface—named ‘Land & Water’—which provides public access to model inputs and outputs and was designed considering FAIR (Findable, Accessible, Interoperable, Reusable) principles. A multifaceted calibration approach, combining soft and hard methods, ensures balanced performance for surface, lateral and groundwater dynamics. The platform enables users to visualise and download model results, supporting both experts and non‐experts in water‐related decision making. The study demonstrates how the model helps close critical data gaps—providing estimates of river discharge for transboundary inflows, total and groundwater flow around the Kakhovka reservoir, and potential transpiration and crop growth to assess irrigation needs. Overall, the dataset offers a valuable tool for Ukraine's recovery, fosters transparent water governance, and supports environmental research on water quality, climate adaptation and sustainable agriculture.