Right: This 60-inch diameter corrugated metal pipe culvert, located under Interstate 480 in Cuyahoga County, Ohio, failed on Dec. 14, 2001. The failure and subsequent replacement efforts disrupted travel of almost 170,000 vehicles a day for a little more than a week. Photo: Ken Banaszak, Ohio DOT
Far right, top: Crews survey the site of an emergency repair triggered by a culvert failure along Interstate 70 east of Vail, Colo. Costs to replace this culvert totaled $4.2 million. Photo: Colorado DOT. Far right, bottom: This 66-inch diameter corrugated metal pipe culvert, located under Interstate 70 east of Vail, Colo., failed on June 1, 2003. The failure and subsequent replacement efforts required a 54-mile, two-hour detour of almost 21,000 vehicles a day until repairs were completed on July 20. Photo: Colorado DOT
Analyzing Case Studies
Agencies also were asked by the researchers to submit case studies of culvert failures. For the seven case studies presented in the report, Perrin and Jhaveri found a wide range of traffic conditions, replacement costs, and user impacts and costs.
Four of the case studies presented in the report occurred along interstates; the remaining three occurred along two state routes and a Canadian highway. All failures took place between 2000 and 2003. AADT on these routes ranged from 5000 to 300,000 vehicles with heavy commercial traffic between 3% and 30%. All culvert failures took place in pipes that had met or exceeded expected design life. All but one required detours to be provided, which extended travel times from 20 minutes to 4 hours. Total replacement costs, including user costs, ranged from $265,000 to more than $8 million.
Based on responses, Perrin and Jhaveri report that “some of the failures had met the agencies' expected life for that pipe type but no planned replacement was scheduled. This raised the concern that there is a lack of inspection and/or tracking of useful life expectancy.”Preventing Failures
Perrin and Jhaveri conclude in the report that the “reality is that pipes are not being replaced as they approach their expected design life. Only one agency inspected all culverts within its jurisdiction every two years and there are no reported failures from that agency.”
Based on case studies and survey results, the authors offered the following observation. “By quantifying the additional costs of emergency replacement it is clear that an inspection/maintenance program provides an attractive cost benefit.”
In addition to setting up a regular inspection and maintenance program for culverts, the authors stressed the importance of adding replacement costs of the culvert and user costs to the LCCA in order to obtain a more accurate cost of culvert placement.
The authors suggest “a need to establish a standard procedure of documenting culvert failures and expand the existing limited data into a nationwide database.” They call for AASHTO or TRB to take the lead in development of such a report.
— This article was developed and portions of it excerpted from “The Economic Costs of Culvert Failures,” by Joseph Perrin Jr. and Chintan S. Jhaveri. The complete report is at the TRB site at www.trb.org or the ACPA site at www. concrete-pipe, org.