Integrating Nature-Based Solutions into Urban Spatial Planning: Stormwater Management, Green Space Optimization and the Urban Bioeconomy

Rapid urbanization and surface sealing have exposed the limits of conventional grey stormwater infrastructure, prompting a shift toward multifunctional blue–green infrastructure (BGI). This integrative review evaluates six nature-based solution typologies—rain gardens, blue–green roofs, bioswales, constructed wetlands, retention ponds and permeable paving systems—as instruments of urban spatial planning, through a bioeconomic lens. Searches of Scopus and the Web of Science Core Collection, supplemented by Google Scholar, yielded 272 publications classified by publication period, research method and thematic domain. The evidence is uneven: 43.4% of records address hydrological function, and 17.3% bioeconomic valuation; 49.3% are reviews or conceptual contributions, and only 8.8% apply a formal economic valuation technique. The reviewed literature indicates that the six typologies are complementary rather than substitutable, occupying distinct treatment-train positions—source control, conveyance and sub-catchment attenuation—and that hybrid green–grey configurations are more robust under extreme events. Applied economic valuation was identified for rain gardens and permeable paving, partially for blue–green roofs and bioswales, and not for constructed wetlands or retention ponds. Lifecycle cost analysis, disservice-adjusted valuation and performance-based planning instruments, rather than further hydraulic documentation, are likely to be decisive for adopting BGI as a standard municipal utility.