A Comparative Analysis of the Effectiveness of Nature-Based Stormwater Management Solutions at the Neighbourhood Scale

Water is a primary resource for humans to live; however, due to the high urbanization and the effects of Climate Change, impervious urban surfaces have largely increased, which easily leads to flood problems during intense rain events, threatening the resilience of the built environment and communities. Nature-Based solutions (NBSs) are deemed as effective means to address water-related hazards; furthermore, they can contribute to climate change adaptation and mitigation, thus improving urban resilience. However, their effective planning and implementation is still difficult because it lacks a comprehensive framework for their integration in existent environments. This paper aims to pave the ground for future studies on this gap and explore integrated hydrological contributions for designing resilient cities. To accomplish this, the authors compare the effectiveness of the most popular Nature-Based stormwater management solutions (green roofs, rain gardens and vegetated swales) at the neighbourhood scale according to two relevant hydrological performance indicators: runoff volume reduction and peak flow reduction. It also evaluates their contribution to urban resilience with relevant resilience indicators. In conclusion, these three solutions show high efficiency in managing stormwater but vary in contributing to resilience performance regarding their own characteristic. KEYWORDS: Nature-Based Solutions, runoff volume reduction, peak flow reduction, stormwater management, urban resilience