Floods are natural events typically occurring in regions with intense rainfall. The South District of Dera Ismail Khan in Khyber Pakhtunkhwa (KP), Pakistan, is particularly vulnerable to such events, which frequently lead to destructive floods, causing significant damages. This chapter presents a comprehensive methodology for flood risk modeling in Dera Ismail (DI) Khan, using a multi-criteria decision-making analysis (MCDA). Following the devastating 2022 floods, the study aims to improve flood risk management strategies in this susceptible region. The factors considered in this study include the topographic wetness index (TWI), elevation, slope, land cover, precipitation, stream distance, drainage density, and soil type. These factors were assigned weights and ranks through the Analytic Hierarchy Process (AHP) and analyzed within a GIS to develop a flood risk assessment model. The resulting flood risk map identified three risk zones: low (15.74%), moderate (59.60%), and high (24.66%). The model was validated by the 2022 flood extent, with approximately 88% of past flood occurrences aligning with the high-risk zones identified in the model, confirming its reliability. Ultimately, the integration of GIS and AHP provides a quick, reliable method for flood risk assessment, which can be applied to other flood-prone regions globally.