NC DOT Engineer Ordered Extra Inspections of State’s Truss Bridges

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2010

A senior state transportation official ordered extra inspections of truss bridges like one that collapsed last week on an interstate highway in Washington state, but he said that North Carolina’s 13,500 state-maintained bridges are safe, reports the News & Observer.

“We have our two-year bridge inspection program, and we crawl all over every bridge we have,” said Terry Gibson, chief engineer for the state Department of Transportation. “If we find a problem, we address it.”

Like other states, North   Carolina has struggled to reduce a backlog of aging bridges overdue for replacement. The legislature has set aside more money for the effort – $450 million in the past two years. DOT has modernized its strategy for rebuilding the worst bridges and aiming rehab efforts at others to prolong their useful lives.

Advocates for transportation investment say the state is making progress, but not enough. ‘We are in a big hole to begin with,” said Charles Hodges, executive director of NC Go, a nonprofit group that lobbies for road and transit improvements. “The good news is that they’ve got some practices in place that are moving the process forward more quickly than in years past. And they are still allocating extra funds to correct the problem. But it’s hard to imagine we’ll ever be caught up.”

DOT replaced more than 560 bridges and did preservation work on 450 more over the past two years, Gibson said. He said 736 bridges that were rated in poor condition will be elevated into the “good” category when these projects are completed.

He spoke a day after a four-lane Interstate 5 bridge span fell into the SkagitRiver north of Seattle. Washington authorities blamed a too-tall truck that struck the overhead steel truss frame supporting the structure. Three people were rescued from two cars that fell into the river.

North Carolina has 35 truss-style bridges, Gibson said. “I’m going to ask our division offices to go out and take a look at their truss bridges to make sure they’re safe,” Gibson said. “We don’t expect to find any issues.”

After 13 people died in the 2007 collapse of a freeway bridge in Minnesota, North Carolina officials said they would need to quadruple the pace of bridge replacement – then about 200 new bridges a year – to catch up with the demand.

Gibson said DOT makes its bridge dollars go farther these days. “It used to be the way we approached bridges was, we replaced them,” Gibson said. “Now we’re learning we can go in and strengthen the columns or rehabilitate the bridge deck, and keep it in good condition. We can get a lot of life out of a bridge for less money.” Hodges and Gibson said DOT also is saving time and reducing costs by bundling small bridges together in “express design-build” jobs.

Separate, multimillion-dollar contracts are still required for big freeway structures such as Capital   Boulevard and Interstate 440 Beltline bridges that date from the 1940s to the 1960s. But DOT now combines smaller, two-lane bridges to give a single contractor two or three years to design and build seven to 10 bridges on different roads.

The AAA Carolinas motor club keeps tabs on the state’s aging bridges and highlights the worst bridges that carry the most traffic. Last year’s 20-worst list included three in Wake – on I-40, I-440 and Capital Boulevard – that are slated for rehabilitation or replacement.

“A lack of funding has resulted in a significant number of substandard bridges in North Carolina,” said Angela Daley, spokeswoman for the Charlotte-based group. “There’s certainly more that needs to be done.”

Gibson told a House-Senate transportation panel last year that the added funds were helping DOT reduce its bridge backlog, but it was important not to divert too much money away from highway repaving and other road needs.

Legislators appear likely to reserve more than $300 million of DOT’s $3 billion budget for bridge needs over the next two years. As state leaders match shrinking gas tax revenues with growing transportation needs, Gibson said that looks like the right amount.

“We need to make sure we’re balancing our approach,” he said. “You can get too excited and put too much money there (into bridges). If we pull too much money from our resurfacing, then that side of the house starts to look bad.”   Read More.