A comprehensive framework combining fuzzy decision-making and scenario analysis has been introduced to assess the benefits of low impact development (LID) measures for urban flood management. The study focuses on providing municipal leaders and urban planners with actionable insights to prioritize and effectively implement LID practices.
With rapid urbanization and increasing rainfall intensity driven by climate change, cities like Chengdu, located in Southwest China, face heightened flood risks. The Chenglong Road Subdistrict, characterized by its dense population, is particularly vulnerable due to its insufficient drainage infrastructure. This urgent situational backdrop establishes the need for deploying efficient stormwater management strategies and highlights the importance of comprehensive evaluations of LID benefits.
The authors of the article outline their multi-indicator fuzzy comprehensive benefit evaluation methodology, which integrates qualitative and quantitative features to assess various LID configurations. By leveraging the Storm Water Management Model (SWMM) alongside ArcGIS for scenario-based analysis, they aim to improve the decision-making robustness for LID implementations. This innovative approach not only considers technical quantitative data but also incorporates uncertain but relevant qualitative insights through expert evaluations.
The methodology was applied within the Chenglong Road Subdistrict, where 26 LID configurations were simulated under five distinct rainfall return period scenarios: 5, 10, 20, 50, and 100 years. Results indicated significant potential benefits with specific LID combinations, particularly using sunken green spaces and permeable pave, leading to impressive reductions in both runoff volume and peak flow rates. The findings are timely and pertinent, delivering clear guidelines for urban flood mitigation strategies.
The results found through SWMM simulations demonstrated comprehensive benefits for LID measures, from eco-environmental refinements to economic advantages. Specifically, when evaluating configurations, the study revealed synergies between three primary LID measures - sunken green spaces, permeable pavements and green roofs - emphasizing the value of synergistic approaches over disjointed implementations.
More so, the analysis conducted signaled the necessity of accounting for various rainfall intensities to understand the broader efficacy of LID applications under changing climate conditions. The results suggested some configurations yielded superior performance during lower intensity rainfall events, whereas others excelled as rainfall intensities escalated. This stratification offers stakeholders insights when tailoring flood management strategies.
Highlighting key aspects of their findings, the authors found “the comprehensive benefits of LID configurations were conducted under five rainfall return period scenarios.” This statement encapsulates the core of their research—balancing nuanced scientific assessments of LID measures through established empirical data with expert evaluations, thereby enhancing objectivity within municipal decision-making processes. Further, the findings bolster the notion for adapting LID measures to align with localized environmental conditions, reinforcing their applicability as practical solutions for urban planners.
Another notable takeaway from the research is the call to action for city planners to “identify practical LID implementation priorities for decision-makers.” This recommendation emphasizes the practical application of the findings, addressing the necessity for locally adaptive LID solutions. The combination of LID measures can alleviate urban flood risk and promote eco-friendly infrastructure, positively influencing urban resilience and sustainability.
Overall, the study concludes by reiteratively emphasizing the importance of LID solutions, urging municipal authorities to not only evaluate their benefits holistically but to also adopt layered LID strategies for cohesive urban flood management. With relevant insights grounded firmly within scientific metrics and expert consensus, the authors open avenues for advancing urban climate resilience and environmental stewardship through informed planning and community engagement.