Abstract Manager

The New Brunswick Department of Transportation and Infrastructure (NBDTI) highway network contains over 3000 culverts greater than 1.2 m in diameter.  This inventory exhibits similar condition issues to the rest of North America, possibly more urgent due to harsh water conditions, multiple freeze thaw cycles and relatively low maintenance budgets.  Recent analysis has suggested that approximately 40% of the large culvert inventory is expected to require replacement or rehabilitation within the next 10 years. 

As part of the Department’s strategy to address this backlog of deteriorating culverts, a rehabilitation program was implemented in 2021.  The goal is to defer the high costs of conventional excavations and replacements, especially in deep fill embankments and high traffic roads. 

Although select culvert rehabilitations were carried-out in the past, the allocation of incremental funding toward rehabilitations ensures that these projects are not in competition with priority culvert replacements for budget.

Since implementation of the program in 2021, eighteen sites, ranging in size between 1.2 m and 3.35 m have been rehabilitated using a mix of conventional and trial methods including slip lining, concrete invert lining, spray-applied geopolymer and shotcrete.  There are five additional sites planned for rehabilitation in 2024.

This paper includes details on the following:

• Culvert inspections
• Identification of potential rehabilitation candidates
• Prioritization process and budget
• Renewal option selection
• Design
• Construction
• Quality Control/Quality Assurance
• Results and lessons learned

In addition to sharing the results of NBDTI’s Culvert Rehabilitation Program, the Department aims to generate further discussion with attendees on their experience with culvert renewals and emerging methods.