This editorial introduces the Digital Water Special Issue, highlighting how artificial intelligence, machine learning, remote sensing, digital twins, and data infrastructure are transforming water monitoring, prediction, control, and planning. The seven featured papers cover water-quality assessment, process control, infrastructure calibration, flood-safe urban design, and responsible data governance. Together, they demonstrate the growing operational value of digital technologies while emphasizing the continued need for human oversight, cybersecurity, ethical responsibility, and equitable data access.