Microbial Induced Corrosion in Ports and Harbors Worldwide

Microbial Induced Corrosion (MIC) consists of microorganisms that through their biological processes, cause metallic elements to corrode at an accelerated rate. Cases have been documented were MIC has accelerated corrosion by as much as 10 times the normal rate. At this rate, structures could be left in an un-repairable condition in a very short period of time, leaving costly total replacement as the only viable option. Although cases of MIC have been documented centuries ago, their abundance and geographic location seem to be spreading at an increased rate in recent years. Cases of MIC have been documented on steel structures submerged in water with all types of salinity, ranging from fresh water to ocean water throughout the world. No specific water quality conditions or geographic phenomenon are known to contribute or inhibit the growth of MIC. Because of the destructive power and unpredictable nature of MIC, it is essential that inspection personnel be well versed in identification and remediation techniques. Identification techniques are typically constrained to visual and nondestructive testing and are carried out through the use of divers during routine underwater inspections. Inspection, testing, and documentation techniques as they pertain to the inspector/diver will be discussed in detail for MIC. In addition, preventative design, in-situ repair, and remediation techniques will also be discussed.