Navigating Water Infrastructure Challenges: Insights into Microbiologically Influenced Corrosion in Drinking Water Distribution Systems

Global population dynamics are shaping the demand for water supply infrastructure, with varying rates of growth across regions. This divergence in population trends presents challenges for water utilities, necessitating adaptation strategies to meet demands. In some regions experiencing rapid population growth, such as certain parts of the developing world, there is a growing reliance on alternative water sources like direct potable reuse due to constraints on traditional supplies. However, the adoption of such unconventional sources introduces complexities in ensuring microbiological
safety. Moreover, the aging water infrastructure in many developed nations
exacerbates these challenges, with increasing incidents of pipe failures and water losses. Beyond the tangible consequences of water loss and infrastructure damage, there are significant implications for water quality. The infiltration of contaminants into the network poses risks of biofilm formation, corrosion, organoleptic issues, and compromised flow efficiency. Addressing these multifaceted challenges requires not only substantial operational adjustments but also significant capital investments, highlighting the pressing need for innovative approaches in water management and infrastructure development.
In industrial pipeline systems and in drinking water distribution systems (DWDS),
microbiologically influenced corrosion (MIC), i.e. corrosion affected by the presence and/or activity of microorganisms, poses a significant challenge. Despite advances in our understanding of the microorganisms, mechanisms, and influencing factors associated with MIC, many aspects remain poorly understood. To address these knowledge gaps, the Euro-MIC COST Action (CA2013 – European MIC Network - New paths for science, sustainability, and standards) has been established. Within this initiative, Working Group 5 focuses on developing laboratory test procedures to reproduce and characterize MIC. Given the scarcity of data regarding MIC in DWDS, our study aimed to establish a test procedure using drinking water and corrosion products sourced from a DWDS impacted by secondary water deterioration. C 1010 mild carbon steel coupons were incubated for 35 days in the presence or absence of minimal medium, with abiotic controls included. Molecular microbiological, chemical, and metallurgical analyses were then conducted. By applying the multiple
lines of evidence (MLOE) approach, data obtained from ATP biomass measurements, shotgun metagenome sequencing, water chemistry assessments, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) analysis, and 3D optical microscopy were integrated and analysed. The findings and insights gained from this experiment will be presented and evaluated, shedding light on the mechanisms and implications of MIC in DWDS.

Acknowledgments
This publication/paper is based upon work from COST Action “CA20130 Euro-MIC” (https://www.euro-mic.org), supported by COST (European Cooperation in Science and Technology). COST (European Cooperation in Science and Technology) is a funding agency for research and innovation networks. Our Actions help connect research initiatives across Europe and enable scientists to grow their ideas by sharing them with their peers. This boosts their research, career, and innovation.