MnDOT disputes critical report on 35W bridge

35W bridge construction
Construction on the new I-35W bridge is ahead of schedule. This morning, legislative leaders were given a tour of the construction site where half of the concrete columns for the bridge are already in place.
Photo courtesy of MnDOT

Responding to a harsh assessment over bridge maintenance before the Interstate 35W failure, top Minnesota highway managers defended their approach to that span but said they were recruiting more engineers and changing inspection practices going forward.

Senior Minnesota Department of Transportation officials went before state lawmakers again Tuesday -- this time to offer a detailed response to an investigative report released last month by a law firm hired by the Legislature.

The Gray Plant Mooty report issued in May said money worries, imprecise inspections and disregard of policies at the department may have led to bad maintenance decisions ahead of the Aug. 1 catastrophe that killed 13 people.


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In a 12-page letter delivered to lawmakers at the hearing's outset, Commissioner Tom Sorel insisted bridge safety "has not been compromised because of funding considerations."

"Since 2001, MnDOT has consistently invested heavily in bridge construction projects, particularly in the Twin Cities metropolitan area," Sorel wrote. "When a safety concern arises about a bridge, it is addressed."

He wrote that the bridge had been a lower priority for replacement than some other bridges with fatigue problems. Frequent inspections of the I-35W bridge didn't note those same problems in critical truss features, which would have elevated the bridge on the replacement list.

Sorel also disputed a claim that MnDOT ignored the advice of an engineering firm it had hired to review the bridge's integrity. He noted that the agency was working through URS Corp.'s recommendations at the time the bridge fell into the Mississippi River.

A design flaw surrounding beam-connecting gusset plates and the weight of repaving equipment on the bridge have been the focus of forensic experts examining the collapsed structure. A federal report on the collapse is due later this summer or early fall.

Chief bridge engineer Dan Dorgan said inspectors would have presumed the plates to be properly designed and wouldn't have analyzed their size during routine inspections.

Since the collapse, three Minnesota bridges have been temporarily or permanently closed because of gusset plate concerns.

MnDOT's inspection program has undergone a full-scale review in the last 10 months.

Sorel said the agency hopes to hire eight extra inspectors to place particular emphasis on bridges that lack redundant support features. He warned that a public salary structure that isn't competitive with the private sector could make it hard to reach the personnel goal.

Rep. Melissa Hortman talked of changing a law that says state employee salaries can't be higher than the governor's.

"It may be that the marketplace says an engineer is a more valuable asset than a governor," said Hortman, DFL-Brooklyn Park.

Other internal changes at MnDOT include adopting a more streamlined system for reviewing inspection reports and ordering fixes when deficiencies are found. That also involves revising ratings dealing with weight on bridges.

Hours before lawmakers focused their attention on the old 35W bridge, they boarded a bus from the Capitol to get an up-close look at its unfinished replacement.

They were on hand as workers slid into place the 60th of 120 pre-cast concrete sections on the new Interstate 35W bridge. They watched from an adjacent bridge as the 170-ton piece was hoisted by a crane and installed. Several marveled at how fast the replacement span has been raised.

"It's like Legos," Rep. Alice Hausman, a St. Paul Democrat, said as the construction crew positioned the sections' teeth and tubes before they were locked together with epoxy.

The final concrete pieces on the 10-lane bridge are expected to be attached next month. But Jon Chiglo, who is overseeing the project for the department, said final work such as installation of electrical and drainage elements will keep traffic off the bridge until mid-September or later.

The contractors have a financial incentive to get done sooner than the Dec. 24 deadline they offered in their winning bid. The builders can earn up to $27 million in incentives if they finish 100 days ahead of schedule, less for every 10-day increment that passes.

Work is done around the clock. At the construction's peak there were 600 people working on the project; now it's closer to 350 per day, Chiglo said.

In response to Sen. Terri Bonoff's question, Chiglo downplayed the possibility the bridge will be opened to motorists prior to the Republican National Convention in early September. He said construction vehicles might be seen driving on the bridge in late August.

"We're not focusing on any convention," Chiglo said.

Bonoff, DFL-Minnetonka, said she wouldn't be bothered if it was an unspoken goal.

"I don't think that's a bad thing," Bonoff said. "We'd all like to show the best face of our cities."

Many of the lawmakers were pleased to hear that cost overruns are expected to be within 1 percent of the original $234 million price tag, and that there have been only 11 minor injuries to construction workers.

(Copyright 2008 by The Associated Press. All Rights Reserved.)