Microbiologically influenced corrosion (MIC) is a widely recognized threat in the energy industry. Oil and gas production activities can introduce potentially damaging microorganisms to the midstream sector, impacting integrity of pipelines, tanks, and other assets. Stagnant or low flow areas where water accumulates are uniquely susceptible to microbial attack; these zones are important to test for microbial community composition as microbes harbored here can differentiate to form biofilms, leading to advanced corrosion rates and failures.
The microbial communities of water collected from seven dead legs were characterized using molecular microbiological methods (MMM) in Fall 2024 before the pipeline underwent winterization, and from the same locations in Summer 2025. Next generation sequencing (NGS) was used to identify the complete microbial community alongside quantitative polymerase chain reaction (qPCR) to detect specific corrosive biomarkers. MIC-related microbes including sulfide-producers, acid-producers, biofilm-formers, and corrosive biomarkers (micC and micH) were found. Shifts in ecological diversity occurred from Fall to Summer, with certain corrosive microbes increasing in abundance, including sulfate reducing bacteria, methanogens, and those containing the micH biomarker. Identifying growth trends of microbes responsible for MIC helps inform risk management and approaches to asset integrity.
