Author(s): Wenhui Wu; Maziar Korzani; Lucy Marshall; Ana Deletic; Behzad Jamali; Kefeng Zhang
Linked Author(s): Behzad Jamali
Keywords: Blue-green infrastructure Water sensitive urban design Urban catchment Surface flooding
Abstract: As pluvial flooding intensifies under climate change, Nature-Based Solutions (NBS) offer a promising solution to mitigate flooding by capturing and reducing runoff. However, planning effective NBS for pluvial flood mitigation is challenging due to the wide range of potential implementations across a catchment, complex interactions with stormwater drainage networks, and high computational demand for detailed flood modelling. Existing target-oriented approach, while effective for rapid, exploratory planning of NBS for stormwater quality and quantity control, struggles with pluvial flooding reduction objectives. We propose a framework that generates NBS strategies to meet annual average damage reduction (AAD) targets in a fast and exploratory manner. The framework employs efficient scenario exploration by screening flood volume reduction scenarios under individual design storms. It then takes a data-driven approach to identify the minimum required flood volume reduction for the desired decrease in AAD as NBS planning targets. After implementing NBS in the screened scenarios, the most probable and effective NBS strategies are selected for long-term performance assessment. A semi-continuous simulation approach is applied to reduce simulation time whilst accounting for antecedent condition in NBS prior to each flood-inducing rainfall event. The effectiveness of the probable strategies in AAD reduction and their life-cycle cost is evaluated for decision-making. This framework empowers stakeholders with clear communication on the long-term benefits of NBS implementation and offers a valuable tool for rapidly identifying NBS strategies for a set long-term flood mitigation target at a catchment scale.
Year: 2025