Assessing the vulnerability of urban areas to natural hazards with an emphasis on urban floods, case study: Lar city

Urban flooding is a significant natural hazard, necessitating the precise identification of susceptible zones for effective management. This study aims to evaluate and zone urban flood susceptibility in the city of Lar, Iran. To achieve this, ten key criteria were selected, including spectral indices (NDBI, NDVI, BSI) and topographical and hydrological features (elevation, slope, TWI, SPI, distance to rivers, soil texture, and precipitation). Following data standardization and fuzzy transformation, the criteria were weighted using the Analytical Hierarchy Process (AHP). Subsequently, a final susceptibility map was generated using the Weighted Linear Combination (WLC) method within a Geographic Information System (GIS) environment.The results of the weighting process indicated that “distance to rivers” (0.223) was the most influential factor, followed by precipitation and the Topographic Wetness Index (TWI). Analysis of the final map revealed that 43.3% of the study area falls into high and very high susceptibility categories, primarily concentrated in the central and northern sections of the city. This spatial distribution is largely attributable to the overlap of topography, proximity to river channels, and impervious surface characteristics. Ultimately, the integration of GIS, fuzzy logic, and AHP proved to be an effective strategic tool for runoff management and urban planning to mitigate flood risk in Lar.