Extent of Corrosion May Limit Repair Options

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

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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: 3132
Revision Date: 09/15/2022