This research group developed an automated, quantitative design method for water-sensitive, sustainable design, considering water runoff and water capture to reduce pluvial flooding on-site and surrounding. The automated method starts with a water runoff analysis using a particle-based approach to identify heights, slopes, flood points and flow lines. These are then used to categorise a grid of cells or points for different programmes, including HDB estate facilities, water related facilities and ABC water strategies. Subsequently, a Cellular Automaton is developed to clean up the point sets into consolidated areas. In a final step, Stable Diffusion is adopted to generate a corresponding master plan. The design method can be automatically applied to varying sites, offering the designer both an analytical understanding of the site conditions and a possible design outcome.