Assessing Flood Risk through GIS-Based Weighted Overlay and 1D Flood Simulation in Critical Sub-Catchment

作者：Ajay Kalra, Utsav Parajuli, Omar Faruk, Md Sayeduzzaman Sarker, Abhiru Aryal, Bishal Poudel, Ritu Gupta · 年份：2024 · DOI：10.1061/9780784485477.005 · 被引用次数：4 · 研究领域：Flood Risk Assessment and Management、Hydrology and Watershed Management Studies、Soil erosion and sediment transport

Urban flooding is the result of the increase in impervious areas and changes in rainfall patterns. The study can be based on flood simulation and mapping of the creeks to prevent urban floods. Flooding in a small area and catchment is not given high significance and is understudied. Therefore, this study aimed to develop the framework for the comparison of flood extent generated using the Personal Computer Storm Stormwater Management Model (PCSWMM), geographic information system (GIS)-based weighted overlay method, and compromise programming method (CPM) for identifying the potential flood risk zone. The primary comparison is among the flood risk extent from hydraulic modeling in PCSWMM and analytical hierarchy process (AHP) by applying nine flood conditioning factors in the GIS-based weighted overlay method. Later, the prioritized list developed from CPM is overlaid in the flood risk extent to identify the critical sub-catchments. As a result, the flood extent from the PCSWMM-based and GIS-based methods showed similarity in flood risk zones in the upstream and the mid-portion of the watershed. CPM identified the upstream and downstream as a high-risk zone of the watershed. The overlapped flood risk extents in the watershed and prioritized sub-catchments show the high and moderate flood risk zone with their similarities and differences, which are crucial for planning flood-resilient urban infrastructure since the limitation of one model could be overcome by the other.