INTEGRATED DECISION SUPPORT SYSTEM FOR PRIORITIZING SEWER SYSTEM REHABILITATION: A GIS-AHP APPROACH

Abstract

Sewer networks form a part of modern society's critical infrastructure, due to their function that ensures public health and environmental protection in urban areas and their capital-intensive nature. These systems, however, have been undergoing deterioration, malfunctioning and overloading, mainly caused by their long lifetimes, inadequate maintenance, or population growth. These issues require repair or rehabilitation. Still, due to an insufficient sewer system rehabilitation budget, utility managers have been forced to prioritize competing projects. Therefore, prioritizing sewer rehabilitation interventions have become crucial to address these problems and optimize the allocation of limited resources. This study proposes an integrated decision support system integrating the Analytic Hierarchy Process (AHP) and Geographic Information Systems (GIS) to prioritize sewer system rehabilitation in Gdyel, Algeria based on both physical and hydraulic criteria. A set of 18 indicators ware used to rank sewer network of Gdyel city, under two different scenarios. The results showed that 13% of the network in Scenario 1 and 31% in Scenario 2 require urgent intervention. In addition, a methodology was introduced to confirms the proposed approach accuracy, which effectively aligned high-priority areas with known high-risk zones.