Hunt for Victims, Clues

MINNEAPOLIS - Minnesota officials were warned as early as 1990 that the bridge that plummeted into the Mississippi River on Wednesday was "structurally deficient," yet they relied on patchwork fixes and stepped-up inspections that unraveled amid a thunderous plunge of concrete and automobiles.

"We thought we had done all we could," state bridge engineer Dan Dorgan said yesterday not far from the mangled remains of the span. "Obviously, something went terribly wrong."

Questions about the cause of the collapse of the Interstate 35W bridge during the evening rush hour, and whether it could have been prevented, arose as authorities shifted from rescue efforts to searching for bodies that might be hidden beneath the river's swirling currents.

The official death count stood at four, with 79 injured. But police said the death count would surely grow because bodies had been spotted in the water, and as many as 30 people were still reported missing.

The Army Corps of Engineers lowered the river level a foot to help recovery efforts, spokeswoman Shannon Bauer said.

Federal officials alerted states late yesterday to immediately inspect all bridges similar to the one that collapsed. Also yesterday, Congress began working on $250 million worth of federal aid to help Minnesota replace the bridge, and Transportation Secretary Mary Peters announced a $5 million grant to help pay for rerouting traffic, clearing debris, and repairs.

President Bush made plans for a visit tomorrow to Minneapolis, which will be host to next year's Republican National Convention. He was sending Laura Bush there today to console victims.

"We in the federal government must respond, and respond robustly, to help the people there not only recover, but to make sure that lifeline of activity - that bridge - gets rebuilt as quickly as possible," Bush said after a cabinet meeting.

In 1990, the federal government rated the I-35W bridge "structurally deficient," citing significant corrosion in its bearings. That made it one of 77,000 bridges in that category nationwide and one of 1,160 in Minnesota.

The designation means at least one portion of the bridge, which was built in 1967, needed to be scheduled for repair or replacement, and it was on a schedule for inspection every two years.

Dorgan said the bearings could not have been repaired without jacking up the entire deck of the bridge. Because the bearings were not sliding, inspectors concluded the corrosion was not a major issue.

During the 1990s, later inspections found fatigue cracks and corrosion in the steel around the bridge's joints. Those problems were repaired. Starting in 1993, the state said, the bridge was inspected annually instead of every other year.

A 2005 federal inspection also rated the bridge structurally deficient, giving it a 50 on scale of 100 for structural stability.

"It doesn't mean that the bridge is unsafe," Peters said after touring the site. "It could carry a rating of 50 for a number of years without getting substantially worse."

At the White House, press secretary Tony Snow said that although the inspection did not indicate the bridge was at risk of failing, "if an inspection report identifies deficiencies, the state is responsible for taking corrective actions."

Gov. Tim Pawlenty yesterday ordered an immediate inspection of all bridges in the state with similar designs, but he said the state was never warned that the bridge needed to be closed or immediately repaired.

"There was a view that the bridge was ultimately and eventually going to need to be replaced," he said. "But it appears from the information that we have available that a time line for that was not immediate or imminent, but more in the future."

The eight-lane bridge was Minnesota's busiest, carrying 141,000 vehicles a day. It was in the midst of mostly repaving repairs when it buckled. Dozens of vehicles plummeted more than 60 feet into the river.

Engineers wondered whether heavy traffic might have contributed to the collapse. Studies of the bridge have raised concern about cracks caused by metal fatigue.

"This is an interstate bridge that sees a lot of truck traffic," said Kent Harries, an assistant professor of civil and environmental engineering in the University of Pittsburgh's School of Engineering.

After a study raised concern about cracks, the state was given two alternatives: Add steel plates to reinforce critical parts, or thoroughly inspect certain areas to see if there were additional cracks. They chose the inspection route, beginning that examination in May.

Dorgan said officials considered the cracks on parts of the bridge stable and not expanding.

The bridge's last full inspection was completed June 15, 2006. The report shows previous inspectors' notations of fatigue cracks in the spans approaching the river, including one 4 feet long that was reinforced with bolted plates. A 1993 entry noted 3,000 feet of cracks in the surface of the bridge; they were later sealed.

That inspection and one a year earlier raised no immediate concerns about the bridge, which was not a candidate for replacement for 13 more years.

In a 2001 report from the University of Minnesota's department of civil engineering, inspectors found that some girders had become distorted. Engineers also saw evidence of fatigue on trusses.

The Hennepin County medical examiner yesterday identified the four people found dead as Julia Blackhawk, 32; Patrick Holmes, 26; Artemio Trinidad-Mena, 29; and Sherry Engebretsen, 60, the St. Paul Pioneer Press reported.

At the scene during the day yesterday, about 15 divers and a dozen boats were in the water, but the search was proceeding slowly because of strong currents and low visibility. By mid-afternoon, they had located four submerged cars besides the dozen or so visible from the surface.

"We have a number of vehicles that are underneath big pieces of concrete, and we do know we have some people in those vehicles," Minneapolis Police Chief Tim Dolan said. "We know we do have more casualties at the scene."

For first-person accounts of the I-35W collapse, a look at past U.S. bridge collapses and more, visit http://go.philly.com/collapseEndText