Community Scale Assessment of the Effectiveness of Designed Discharge Routes from Building Roofs for Stormwater Reduction

Urban flooding is increasing due to climate change and the expansion of impervious land surfaces. Green roofs have recently been identified as effective solutions for mitigating urban stormwater. However, discharge routes that involve receiving catchments stormwater runoff from mitigate high flows limited. Thus, a hydrological model was constructed investigate effects changing on flow. Three hypothetical scenarios were assessed using various combinations roof types. The reduction outflow overflow evaluated across six return periods designed rainstorms in Tai Hung Tulip House community Beijing. results showed green roofs, together with connecting pervious catchments, reducing peak flow (13.9–17.3%), volume (16.3–27.3%), drainage frequency, flood duration. Although mitigation can be improved by considering routes, it limited compared achieved roofs. integrating improve resilience longer periods. These provide useful information design future management strategies small-scale areas.