The Expert Team on Hydrometry (ET-Hydrometry), established in 2024 under SC-MINT and INFCOM, expands the scope of the former Project X to cover a wide range of hydrometric activities and parameters. The team supports the adoption of innovative technologies, develops assessment methodologies and technology transition pathways, promotes freely accessible guidance and standardized approaches, and considers both high-tech and low-cost instrumentation. In 2025, ET-Hydrometry focuses on finalizing guidance for acoustic Doppler current profiler (ADCP) intercomparison events, which help National Hydrological Services compare and verify instruments, foster technical collaboration, and generate valuable datasets for assessing measurement uncertainty.