Extent of Corrosion May Limit Repair Options

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Message: The longer we wait, the fewer options we have. Understanding the severity of corrosion is important to recommend the appropriate rehab method.

Minor corrosion and abrasion can cause superficial rust and minor pitting and can be rehabilitated with a nonstructural method. Moderate corrosion leads to scattered heavy rusting and deep pitting and can be addressed with a semistructural rehabilitation method. Major corrosion can cause structural failure and collapse due to extreme rusting and deep pitting perforations and needs a fully structural rehabilitation method.

Content Courtesy of USDA Decision Analysis Guide for Corrugated Metal Culvert Rehabilitation and Replacement Using Trenchless Technology

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  Moderate corrosion caused heavy rusting and deep pitting in a corrugated metal culvert

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  Major corrosion caused structural failure of a corrugated metal culvert (D.A. Van Dam and Associates and Ohio Department of Transportation)

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  Moderate corrosion allowed piping of embankment material through the conduit, leading to eventual failure of the dam. (damfailures.org)

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  Minor corrosion caused rust and pitting in a corrugated metal culvert

Note: The content on this page was originally created as part of DamOutletWorks.org (DOWL, 2018). It has subsequently been updated and reformatted as part of the Dam Safety Toolbox.
Revision ID: 6864
Revision Date: 06/19/2023