Simple Rating System for Identification of Failure-Critical Culverts and Small Structures

Although bridges are a highly visible and crucial part of the highway infrastructure, smaller structures typically classified as culverts exist in even greater numbers. Nearly invisible to the public, culverts are crucial components of highways. Failure of culverts can lead to flooding, roadway damage, interruption of traffic, and even fatal accidents. Several states have implemented successful culvert inspection programs, but others are only beginning to formalize their culvert inspection and maintenance. Even after periodic inspection programs are in place, planners need a tool for consistent guidance to identify structures most in need of attention. This paper reports on a simple rating system based on a new culvert inspection program recently implemented by the Indiana Department of Transportation. The rating system uses weighting factors that can be adjusted by the user to provide an overall rating of a culvert based on ratings of specific characteristics of a culvert. The tool can be used to provide a consistent comparison with other culverts across the state and to provide quality control of the inspectors’ overall rating as entered into a database.