Climate change is a major global issue, with sea level rise, hurricanes, flash floods, and heat and cold waves all being major threats that have led to significant human and economic losses. Egypt's high-speed electric train project is aiming to reduce climate change and improve public health by providing a greener mode of travel. Flooding is a global threat, particularly in arid regions where it is more severe due to climate change and rapid development. The investigation aims to identify flood-prone zones in the study area, including the proposed third track of the high-speed train Qena-Hurghada-Safaga (QHS), using multi-criteria decision analysis (MCDA). The Analytic Hierarchy Process (AHP) was used to identify seven potential factors for flash floods. AHP was used to assess the significance of each factor in the flood susceptibility map by assigning weights. The most crucial criteria to determine flood-prone locations were surface runoff characteristics (30%), watershed morphometric parameters (22%), and average rainfall distribution (16%). A flood susceptibility map was created by overlaying thematic layers and categorizing them into five categories based on the level of flood intensity in the area. According to the prepared map, the research regions were, in order, very low, low, moderate, high , and very high-prone flood zones (6.04%), (36.02%), (14.63%), (33.30%), and (10.01%), respectively. Finally, the runoff curve number (CN), which regulates the key factor in the flood susceptibility map, was validated using a total of 24 soil samples that were collected along the proposed track between the Red Sea Mountain valleys from Qena to Hurghada. In addition, using receiver operating characteristic (ROC) and area under curve (AUC) analyses, the mapping of flash flood susceptibility was verified. The validation findings revealed an AUC value of 0.81, demonstrating the dependability of the AHP approach. Moreover, some of the recommended technical solutions have been documented to enhance security against such frequent events in particular areas susceptible to flooding and storms.