An integrated approach for urban flood risk prediction using AHP-TOPSIS model: a case study of Jaipur region

Urban floods pose a significant threat to cities worldwide, impacting lives and livelihoods. This study focuses on the urban flood risk assessment of the Jaipur Region, employing a multidimensional approach integrating Geographic Information System, Analytical Hierarchy Process, and Technique for Order Preference by Similarity to Ideal Solution models. The study utilizes morphological, hydrological, and land & socio-economic criteria, comprising 21 thematic layers generated from satellite and census data. The weights assigned to each criterion were obtained through discussion with key authorities along with a meticulous review of research articles using the Analytical Hierarchy Process methodology. The results emphasize the significance of land and demographic criteria, followed by morphological and hydrological criteria. The study reveals that the central and southern parts are highly prone and vulnerable to urban floods/waterlogging in the region. Afterwards, approximately 65 locations were identified and updated with the help of e-new records, key authorities and local resident in Jaipur city and other major towns in the Jaipur Region. Following this, using Google Earth, 780 locations were spatially mapped in a GIS environment. Additionally, to reinforce the study, a random field survey was conducted at 141 (18%) locations to assess the impact of flash floods or waterlogging in the area. The resultant map of the urban risk zone shows that on average about 33% of the area under Jaipur Region falls under urban flood risk. Subsequently, the model's reliability is validated through ROC curve analysis, yielding an Area Under the. Curve (AUC) of 0.849, indicating robust discriminatory power. The Kappa coefficient further affirms the model's accuracy, with an overall agreement of 85%. The study uniquely focuses on future planning areas delineated for upcoming urban.