Inundation risk of sewerage system according to the concepts of hazard and vulnerability-case of Algiers city

Abstract

Algiers city frequently experiences significant flooding during rainy weather due to the overflow of its storm sewer network (SSN). Through modeling, simulation, and field studies, vulnerable points of the network have been identified. These points are classified based on a combined assessment of hazard and vulnerability. Hazard is estimated using the Analytical Hierarchical Process (AHP) method, which considers the return period, overflowing height, slope, elevation, and waterproofing. On the other hand, vulnerability is determined by population density. Risk is determined by multiplying hazard and vulnerability. Additionally, a classification based on the FMECA method's criticality index has been performed to complement the approach. The concordance between the two methods is evaluated using Lin's concordance correlation coefficient (CCC), showing strong agreement. The sensitivity analysis conducted on the models highlights their reliability and robustness, making the obtained results trustworthy and useful for network managers. This analysis aids in effective flood management by allocating resources and interventions to the most vulnerable areas of Algiers city.