Simulation of flood hazard, prioritization of critical sub-catchments, and resilience study in an urban setting using PCSWMM: a case study

Due to the dual pressure of rapid urbanization and climate change, urban flooding has become more common. Thus, for effective planning and mitigation strategies, it is of paramount interest to quantify the generated runoff and prioritize the urban critical sub-catchments. The present study investigates flood inundation in Hyderabad urban setting (zone-XII, zone-IV&V) using the Personal Computer Storm Water Management Model (PCSWMM) and prioritizes the critical sub-catchments using the compromise programming method (CPM) and PCSWMM. In addition, the system resilience is examined by integrating PCSWMM with GIS. The model simulation is performed for a 264 h (11 days) rainfall event that occurred in October 2020. The outcomes from the simulation are found to be satisfactory and in agreement with the field water logging points (WLPs). The inundation map results are validated with social media markers (SMMs). The critical sub-catchments are prioritized based on PCSWMM by runoff results and CPM by considering WLPs, slope and impervious percentage of sub-catchments as input criteria. The Integrated 1D-2D PCSWMM is used to examine the inundation velocity and depth. An urban flood hazard (UFH) map is generated to identify optimal low impact developments (LIDs). Subsequently, the present study showed how storage can improve the catchment capability and resilience of urban settings to tackle the excess stormwater.