The neighborhood recycling potential index: Diagnosing the spatial implementation gap in urban waste systems

Municipal recycling rates alone cannot distinguish whether underperformance reflects spatial deficits or implementation failure. In this study, we develop the Neighborhood Recycling Potential Index (NRPI), a neighborhood-scale diagnostic of recycling participation potential based on accessibility, network permeability, and residential morphology. Using annual district-level waste-flow data for paper and cardboard, glass, organic waste, and total recycling across 17 districts in Lausanne, Switzerland, we found that NRPI varied substantially (0.219–0.750) but showed weak association with aggregate recycling performance. This divergence highlights the key policy signal: potential–performance gaps identify priority areas for intervention and whether the priorities are infrastructural or governance-related. Glass recycling aligned strongly with accessibility and permeability, whereas organic recycling was associated with morphology. Standardizing spatial potential and observed performance yielded a typology distinguishing capital investment from governance-based instruments. Sensitivity analyses indicated robustness across topographic penalties and equal weighting. Overall, NRPI supports decision-making rather than deterministic prediction.