Developing a decision support system for regulating urban runoff by centralized blue-green infrastructure

The expansion of impervious surfaces and climate change have weakened urban drainage systems (UDSs), resulting in frequent urban waterlogging. Compared to decentralized green infrastructure, centralized blue-green infrastructure (CBGI) offers greater storage capacity and better adaptability to future uncertainties. However, the integration of CBGI with gray infrastructure for intelligent runoff assignment and enhanced UDS resilience remains underexplored. This study develops a Smart Stormwater Management ApplicaTion for CBGI (SSMAT-CBGI) to support dynamical and adaptive runoff assignment and storage management for CBGI. By integrating spatial analysis, SWMM, and the NSGA-II algorithm, SSMAT-CBGI can simulate and evaluate different runoff assignment strategies in real time, respond rapidly to rainfall events, and automatically identify optimal control solutions through built-in decision support tools. SSMAT-CBGI was applied to the Central Green Corridor Park in Xixian New Area, Shaanxi Province, China, to evaluate its applicability and control stability under various uncertainty conditions by simulating twelve scenarios. As the return period increased from 5- to 50year, the UDS resilience with CBGI remained above 0.76 (out of 1), and the maximum reduction in peak outflow at the outlet of UDS reached 48.69 %. Even under climate extremes and increased impervious ratio in the future, CBGI can still regulated over 25.93 % of the runoff from drainage units. SSMAT-CBGI with intuitive user interface enables stakeholders to express their concerns and preferences, while also supporting real-time updates and result visualizations.