MnDOT records: Inspectors saw rusty plates on Winona bridge

Bridge inspections
MnDOT workers inspect the gusset plates on the Highway 43 bridge over the Mississippi River in Winona. The bridge was closed for several days this month because of concern over the condition of the gusset plates.
MPR Photo/Brandt Williams

(AP) - Records from the state Department of Transportation show that state bridge inspectors noted rusty gusset plates on the Winona Interstate Bridge as early as 2006, a newspaper reported on Thursday.

The corroded plates were cited as the reason behind the bridge's closure earlier this month. At that time, MnDOT officials said no red flags were noted in prior inspections, and that gusset plates weren't closely examined.

But the Winona Daily News obtained records showing that in 2006 and 2007, inspectors did examine those plates and found "advanced corrosion."

The documents also say that rusty holes were found in gussets on Pier 21 of the bridge -- that's the same pier where inspectors shattered plates with hammers in an inspection this month.

"In the light of the [35W] bridge failure, things are looked at differently. Gusset plates get a lot more attention now than they did then."

MnDOT officials now say those reports didn't spark action because gussets weren't considered a critical bridge component until recently. Failed gusset plates may have contributed to the collapse of the Interstate 35W bridge on Aug. 1.

But at least two state lawmakers said the reports on the Winona bridge and on the I-35W bridge show a pattern where MnDOT officials deferred necessary maintenance.

"All we have is a whole stack of pages documenting problems, and we have no clue whether anybody did anything about it," said Sen. Sharon Erickson Ropes, DFL-Winona.

Sen. Jim Carlson, DFL-Eagan, said the Winona bridge reports reminded him of issues raised in the Gray Plant Mooty report, which legislators commissioned to investigate the collapse of the I-35W bridge. That report suggested that budget woes may have led MnDOT to ignore warnings and defer bridge maintenance.

"There were things that were mentioned for years and years, and they were not addressed," Carlson, who is also a mechanical engineer, said of both the I-35W and the Winona bridges.

In the prior reports on the Winona bridge, inspectors noted missing rivets, rust forcing gussets apart and heavy section loss to corroded plates. MnDOT crews reinforced a single faulty gusset in 2000, according to the reports.

Inspectors "have been noticing corrosion and pack rust on that bridge for awhile," said MnDOT bridge inspector Eric Evens, who evaluated the Winona Bridge in 2006 and wrote one of the reports.

MnDOT structures engineer Craig Falkum reviewed the 2006 and 2007 reports and said the rusty gussets were flagged as a problem, but not as a "critical" concern, even though corrosion had worsened noticeably in the past two years.

But Evens said those findings came before the collapse of the I-35W bridge; now, the National Transportation Safety Board has directed states to pay more attention to gusset problems.

"In the light of the bridge failure, things are looked at differently," Evens said. "Gusset plates got a lot more attention now than they did then."

Sen. Steve Murphy, DFL-Winona and chairman of the Senate Transportation Committee, said doesn't want to blame engineers or inspectors because engineers had "finite resources to take care of a lot of problems."

The Legislature passed a $6.6 billion transportation package earlier this spring that may ease the financial strain on MnDOT, Murphy said.

"Hopefully we've improved the system fiscally to where repairs can take place before things like this occur," Murphy said.

Traffic on the Winona Interstate Bridge will be limited to one lane Thursday and Friday from 9 a.m. to 3:30 p.m. as Minnesota Department of Transportation crews inspect the structure. Once the two-day inspection is done the bridge will be reopened to two lanes.

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Information from: Winona Daily News, Winona Daily News

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