Investigating sewer corrosion drivers using quantitative modeling

Abstract

The corrosion of concrete sewers presents a serious challenge to urban infrastructure, threatening the structural integrity and operational efficiency of wastewater systems worldwide. Corrosion occurs through chemical and biological reactions, where the formation of sulfuric acid due to microbial activity leads to progressive deterioration of concrete surfaces, ultimately weakening the material and accelerating failure. This degradation increases maintenance costs, shortens infrastructure lifespan, and poses risks to public health and environmental safety. Despite extensive research on sewer corrosion, most studies focus on individual factors rather than conducting a comprehensive assessment of all contributing factors. This study addresses this gap by systematically identifying and evaluating the most influential factors driving sewer corrosion. A multi-step methodology was employed, including a literature review to identify key sewer corrosion drivers (SCDs), an expert survey targeting professionals in infrastructure and environmental engineering, and a statistical analysis of the collected data. The findings were further validated using Partial Least Squares Structural Equation Modeling (PLS-SEM) to establish relationships between these factors. The results indicate that environmental drivers (ED) exert the strongest influence on sewer corrosion, followed by operational drivers (OD) and, finally, pipe-related drivers (PRD). These findings offer practical implications for infrastructure engineers, policymakers, and wastewater management agencies by guiding preventive maintenance strategies, optimizing material selection, and improving sewer system design. By implementing these insights, municipalities can enhance the resilience of wastewater infrastructure, minimize unexpected failures, and promote sustainable urban development.