Abstract
BACKGROUND: Immersive technologies-virtual, augmented, and mixed reality (XR)-are being piloted in the water sector for public engagement, training, and decision support. Within the European Commission's ICT4Water Cluster, multiple projects report XR tools, but comparable evidence on functionality, interoperability, and scalability is limited. METHODS: We conducted a two-stage survey across ICT4Water projects (preliminary project-level screening: September-December 2023; tool-level assessment: April-May 2024). Responses were triangulated with public project materials. Seven distinct immersive solutions were analysed using a four-dimension rubric covering functionality, interoperability, scalability, and perceived impact. RESULTS: The portfolio spans VR, AR, MR, decision-support dashboards, and public-facing installations. Reported deployment options include PCs (4/7; 57%) and smartphones (4/7; 57%), with online-only operation in 3/7 (43%) tools and offline capability in 2/7 (29%). Interoperability is uneven: 3/7 (43%) expose data integration or APIs, while 4/7 (57%) lack external interfaces. Evidence of scalability beyond single-site pilots is reported for 4/7 (57%) tools; 3/7 (43%) remain at pilot/proof-of-concept stage. CONCLUSIONS: XR can enhance awareness, learning, and operational insight, yet broader uptake depends on open interfaces, shared semantics, and post-project maintainability. We recommend designing against open standards and Smart Data Models, adopting modular packaging and open repositories to support post-project sustainment, and embedding XR within utility workflows and digital-twin initiatives to enable responsible scale-up.