Nature-Based Solutions for Urban Stormwater Management: Assessment Frameworks and Empirical Evidence—A Systematic Review

This review examines how the hydrological performance of implemented, ground-based urban green and blue infrastructure (GBI) and nature-based solutions (NBSs) is monitored and assessed. It combines bibliometric mapping, a targeted systematic review, and an indicator crosswalk. The bibliometric dataset included 2426 publications, while the targeted review analyzed 12 empirical-monitoring articles and 7 assessment-framework publications. Empirical studies covered catchment and sewershed monitoring, practice-scale inlet–outlet monitoring, and local infiltration or media-hydraulic characterization. Frameworks instead interpreted hydrological evidence alongside broader planning, management, resilience, and governance objectives. The crosswalk compared thirteen water-related functions, of which six were shared between the two corpora. Infiltration was the only function for which the two corpora shared a closely related primary measurand, although even here they relied on different test designs and measurement resolutions. The other five shared functions corresponded functionally, but diverged in measurand, temporal basis, denominator, or comparator. The remaining seven functions were represented in one corpus only, accounting for 26 of the 66 empirical and 23 of the 42 framework indicator records.