Mumbai: IIT-B Study Reveals 'Green Roofs' Can Mitigate Urban Flooding By Upto 60%

Situated in India, a recent study by researchers from IIT Bombay and CEPT University focused on the potential of green roofs to mitigate flooding in densely populated urban settings. The Odhav area of Ahmedabad was selected for evaluating how effective these installations could be in controlling stormwater runoff. Green roofs, consisting of vegetation and soil on rooftops, were analyzed for their flood reduction capabilities in various rainfall scenarios. Researchers developed a detailed computer model that simulated water flow and runoff behavior across different terrains, taking into consideration parameters like soil type and stormwater network layouts. By systematically exploring various scenarios with different percentages of green roof coverage, the study found that the effectiveness of flood mitigation varied significantly based on these conditions. Results demonstrated that when green roofs covered 25% of suitable buildings, flood reductions were minimal, only reaching around 5%. However, as coverage increased to 50% or 75%, the positive impact on flood volume drastically improved. Notably, flood volume reductions correlated with rainfall intensity, revealing that higher rainfall levels could exacerbate flooding if drainage systems were not designed to accommodate such volumes. The implications of this research are significant for urban policymaking. It provides a robust argument for incorporating green roofs as a practical and efficient strategy to enhance urban resilience against flooding. With continued urban expansion and increasing climatic unpredictability, integrating green infrastructure is paramount for sustainable city development.