Audit Finds Errors In Weight Limits On Texas Bridges
By LIZ AUSTIN PETERSON Associated Press Writer
AUSTIN (AP) – Texas failed to post maximum weight limit signs on decaying bridges and the state’s calculations of how much weight some bridges could hold were not clear, according to a 2006 audit by the U.S. Department of Transportation’s inspector general.
The mistakes should have been caught by two Federal Highway Administration bridge engineers whose job it is to check Texas’ work, but the employees were stretched too thin to be effective, the audit said. In the wake of Wednesday’s bridge collapse in Minneapolis that killed at least five people and injured about 100, Texas officials have insisted all of the state’s about 50,000 bridges are completely safe.
But the inspector general’s report suggested some spans may be carrying more weight than they should, possibly compounding existing problems. “In a worst-case scenario, the lack of a correct load rating or the lack of a weight limit posting could allow heavier vehicles to cross and cause severe structural damage or the collapse of a bridge,” the report said. In a response to the audit, the Federal Highway Administration agreed that improvements in its oversight of state bridge inspections and data were needed.
A spokesman for the agency did not return telephone calls seeking comment Friday. Texas Department of Transportation spokesman Mark Cross said his agency was swamped with requests for information and it would take some time to respond to questions about the audit. More than 2,100 Texas bridges were classified under the same structurally deficient rating given to the bridge that collapsed in Minnesota, according to a 2006 report by the Texas Department of Transportation.
Another 7,800 were deemed functionally obsolete, meaning they were not designed to handle the current traffic demand. Most structurally deficient bridges can continue to handle traffic safely if they are properly inspected, the maximum weight they can hold is properly calculated and the correct maximum weight limits are posted, the inspector general’s report said. But officials with the U.S. Army Corps of Engineers found problems with the calculation and posting of weight limits on 9 of the 14 structurally deficient Texas bridges they reviewed, six of which were being used by too-heavy traffic.
For example, one Texas bridge did not have a weight limit sign but could only handle 20 tons, half of the maximum weight for trucks on state roads. Another bridge had been listed with three weight limits in two years ranging from 25 tons to 99 tons. But there was no proof that the bridges’ structural conditions had changed enough to support the varying calculations.
The corps found similar problems in other states and estimated that the load ratings for about 10 percent of the thousands of structurally deficient bridges on the National Highway System are inaccurate. But Federal Highway Administration engineers have little time for bridge oversight, the auditors found. The agency’s bridge engineer in Texas told the auditors he only spent about 15 percent of his time overseeing the bridge inspection program.
The rest was spent providing technical assistance, inspecting construction and participating in committee meetings. That meant the engineer and his assistant were only able to conduct follow-up reviews of 48 bridges each year, about 1 percent of the state’s total. And he did not necessarily select bridges for review based on whether they had been identified as deficient, the auditors said.
(Copyright 2007 by The Associated Press. All Rights Reserved.)
