Civil infrastructure and MIC corrosion

Many components of civil infrastructure, such as bridges, tunnels, and sheet piles, are constructed from structural metals. These materials can be susceptible to microbiologically influenced corrosion (MIC). MIC occurs when microorganisms, such as bacteria, archaea, and fungi, form biofilms and produce substances that attack metals. For example, sulfate-reducing bacteria convert sulfate into hydrogen sulfide, thereby creating corrosive conditions.

Early identification of high-risk areas, combined with regular monitoring and maintenance, is essential to limit damage caused by MIC corrosion.

MIC corrosion in bridges

In bridges, MIC corrosion can occur when microorganisms colonise metal surfaces and initiate or accelerate corrosion processes. Bacteria can form biofilms, particularly in wet areas, parts of the bridge that come into contact with water. This can accelerate the deterioration of steel and other metal components of the structure. MIC can thus contribute to material degradation and structural weakening. Regular inspection and maintenance are therefore essential to ensure the service life of bridges.

MIC in sheet piling

Sheet piling consists of steel or concrete structures that are placed vertically in the earth to hold back soil or water. When exposed to fluctuating water levels, they can be susceptible to a very rapid form of MIC corrosion, also known as accelerated Low Water Corrosion. This can cause defects in sheet piling, resulting in subsidence of the surrounding area. A similar mechanism can be observed in car parks, where pitting corrosion occurs when steel sheet piling is regularly in contact with water.

MIC in offshore wind farms

Conditions that promote microbial corrosion can arise on the monopiles of offshore wind turbines. The high salinity accelerates corrosion, and the nutrients present in seawater encourage the growth of microorganisms that cause MIC. If monopiles lack adequate protection, corrosion can occur rapidly. In both oxygen-rich and oxygen-poor zones, bacteria can become active, causing or accelerating corrosive reactions. This creates a risk of both chemical corrosion and MIC‑related degradation.

How Microbial Analysis can help you

Microbial Analysis investigates both the causes of MIC corrosion and potential preventive solutions. Based on our research, we draw up a suitable mitigation plan to limit further damage. This may involve applying an anti-corrosion coating, implementing cathodic protection, or other measures aimed at controlling microbial growth.

MIC Prevent Services MIC Diagnostic

Do you suspect that MIC corrosion is a factor in your structures?

Please contact Rob Elzinga or Elsemiek Croese.

elzinga@microbialanalysis.com croese@microbialanalysis.com