Assessing the Impact of Green Infrastructure on Urban Flood Resilience

Thesis Abstract

Urban flooding poses a significant challenge to sustainable city development, exacerbated by rapid urbanization, climate change, and inadequate drainage infrastructure. This study investigates the role of green infrastructure (GI) in enhancing urban flood resilience, aiming to evaluate the extent to which specific GI components—such as permeable pavements, green roofs, rain gardens, and urban wetlands—contribute to mitigating flood risks in densely populated urban neighborhoods. The primary objectives are to quantify the effectiveness of GI in reducing surface runoff, analyze community capacity for flood management through green spaces, and develop a comprehensive model linking GI deployment to flood resilience outcomes. Adopting a mixed-methods research design, this study combines quantitative spatial and hydrological analyses with qualitative assessments of community perceptions and governance structures. The research population includes urban planning agencies, environmental departments, and residents of flood-prone districts within the city, with a total population of approximately 25,000 residents in five key neighborhoods. A stratified random sampling technique is used to select 500 residents for household surveys and 50 urban planners and environmental officials for key informant interviews, ensuring diverse perspectives. Data collection instruments encompass GIS-based spatial analysis, hydrological monitoring sensors, structured questionnaires, and semi-structured interviews. Hydrological data are collected over a 12-month period to capture seasonal variations, while surveys and interviews explore perceptions, practices, and institutional readiness related to green infrastructure. Data analysis utilizes statistical techniques such as multiple regression analysis to identify relationships between GI features and flood mitigation performance, while ANOVA tests compare flood resilience indicators across neighborhoods with varying levels of GI implementation. Thematic analysis is applied to qualitative interview transcripts to examine community and institutional perspectives on GI’s effectiveness and barriers to implementation. A conceptual model grounded in the theory of Sustainable Urban Resilience and the Social-Ecological Systems framework is developed to illustrate how green infrastructure interacts with ecological, social, and institutional factors to influence flood resilience. The expected key findings indicate a significant negative correlation between the extent of green infrastructure and surface runoff volume, with neighborhoods deploying more GI components experiencing markedly reduced flood incidences during peak rainfall events. Additionally, community awareness and participatory governance are identified as critical mediators in the successful integration of green infrastructure strategies. The findings are anticipated to fill gaps in empirical evidence concerning the spatial efficiency and socio-institutional dynamics of green infrastructure in urban flood management, providing a nuanced understanding of its multifaceted impacts. This research contributes to academic discourse by advancing theoretical understanding of green infrastructure’s role within the resilient city paradigm, integrating hydrological, social, and institutional dimensions into a unified analytical framework. Practically, the study offers policy-relevant insights into optimal GI deployment, maintenance strategies, and community engagement processes to bolster flood resilience. The main conclusion underscores that strategic investments in green infrastructure significantly enhance urban flood mitigation capacity, contingent upon effective governance and community participation. Recommendations include prioritizing GI in urban master planning, fostering multi-stakeholder collaborations, and designing community-based education programs to increase acceptance and sustainability of GI interventions. The study advocates for further longitudinal research to monitor the long-term impacts of green infrastructure investments under changing climate conditions and urban growth patterns.