Development of an interactive web-based tool for flood risk analysis and climate–resilient road drainage design: RiskDRAIN

As climate change intensifies extreme rainfall, traditional design storm methods based on stationary assumptions are increasingly inadequate, often leading to misdesigned drainage infrastructure. To address this and manage projection uncertainties, we developed RiskDRAIN, a web-based application designed for the risk-based adjustment of projected design storms. RiskDRAIN, which stands for Risk -based D esign for R esilient A daptation to I nfrastructure N eeds, integrates risk analysis with Canadian downscaled CMIP6 projections (CanDCS-M6). The framework incorporates Intensity-Duration-Frequency (IDF) curves derived from the IDF-CC tool, considering two projection techniques (Clausius-Clapeyron scaling and Equidistance Quantile Matching) with GEV and Gumbel distributions, covering a range of emission pathways (SSP2-4.5, SSP5-8.5) and future horizons. Through an interactive interface, users refine design storms by evaluating provincial and site-specific risks derived from hazard exposure and multi-dimensional vulnerability (socio-economic, transportation, and environmental). Validated through a highway drainage case study, RiskDRAIN empowers practitioners with a data-driven platform for cost-effective, climate-resilient infrastructure planning.