MINNEAPOLIS -- The day after the devastating crash of a busy Minneapolis bridge into the Mississippi River delivered neither answers nor relief.
Clutching snapshots of their loved ones and offering the license plate numbers of their relatives' vehicles, families of the 20 to 30 presumed dead grappled with uncertainty of when the missing would be found. The fate of the dead was decided in an instant, but the bodies might take days to recover.
"It's the not knowing that eats you up," said Dorothy Svendsen, whose son Greg Jolstad, a construction worker on the bridge, is among those missing and presumed dead.
The official death toll was four, yet officials know it will climb when bodies are removed from cars buried under tons of concrete and steel bars and the swirling currents of the river. As many as 30 people were reported missing, police said, and bodies had been spotted in the water.
The bridge - Minnesota's busiest, carrying 141,000 vehicles a day - had a nearly two-decade history of worrisome inspection reports. Yet only modest repairs were made, a common approach in a nation with about 77,000 bridges that share the federal "structurally deficient" designation.
"We thought we had done all we could," state bridge engineer Dan Dorgan told reporters not far from the mangled remains of the span. "Obviously, something went terribly wrong."
Questions about the cause of the collapse, which injured 79 people, and whether it could have been prevented arose yesterday as authorities shifted from rescue efforts to a grim recovery operation.
In 1990, the federal government gave the Interstate 35W bridge a rating of structurally deficient for significant corrosion in its bearings. The bridge is one of 77,000 bridges in that category nationwide, 1,160 in Minnesota alone.
The designation means some portions of the bridge needed to be scheduled for repair or replacement. It was on a schedule for inspection every two years.
Dorgan said the bearings could not be 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.
Yesterday, federal officials alerted states to immediately inspect all bridges similar to the one that collapsed; many had already begun doing so.
Congress began working on $250 million worth of federal aid, and President Bush made plans to visit the site tomorrow.
"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.
Still stung by criticism of the government's sluggish response to Hurricane Katrina, Bush talked with state and local officials in Minnesota. The administration also sent officials to the scene.
Meanwhile, the search mission bogged down in hazardous conditions yesterday, raising families' anxieties. At midday, divers were temporarily pulled from the Mississippi River and searchers were removed from the entanglements of steel and concrete on the crumpled bridge because officials feared the teetering structure and waters were unsafe.
A dam was closed to lower the river by at least a foot to make recovery easier in 9-foot waters.
But the going will be slow, officials said.
The swift-moving river, filled with as many as 50 vehicles, was clouded with grease and oil that made diving like groping in a fog. People's belongings - pens, papers, handbags, shoes - floated about. Atop the river, crushed cars were wedged amid chunks of concrete and twisted steel that at any moment could shift.
"It happened so fast," Svendsen said in a telephone interview from Hinckley, Minn., speaking of her missing son, "and now it will take so long to find him - if they ever do."
He had been working on the resurfacing of the bridge, pushing a piece of rotating construction equipment, when co-workers saw him disappear in a cloud of collapse. Nearby, a bread truck driver was apparently burned in the wreckage of his cab that caught fire. He was not found by nightfall yesterday, authorities said, as it was too dangerous to approach the wreckage that hung on a jagged edge of the bridge.
Other drivers, too, were missing in cars that seemed to have vanished from the roadway. Divers reported yesterday that several submerged vehicles were entombed by huge swaths of concrete and mangled rebar in the Mississippi depths.
"It's a very dangerous situation around there," said Hennepin County Sheriff Richard Stanek. "There's a lot of debris."
Authorities planned to bring in sonar equipment, cranes and other heavy machinery to pluck through the wreckage. Officials of the U.S. Army Corps of Engineers, helping in the debris removal effort, said the salvage work would be hampered because the site is a submerged morgue. Detailed forensics means that every piece of concrete and metal will need to be carefully removed so bodies can be meticulously recovered.
"The recovery involving those vehicles and the people who may be in those vehicles is going to take a long time," Minneapolis Police Chief Tim Dolan said. "We're dealing with the Mississippi River. We're dealing with currents, and we're going to have to do it slowly and safely."
For Twin Cities residents, the bridge was a proud symbol of the region. "You get on that bridge and see the lights of the city, and isn't that wonderful? We're home," Sharon Marie Francis, 62, of Eden Prairie, Minn., said after a prayer service yesterday for the victims. "That's the bridge that tells you you're home in Minneapolis."
Upstream, concerned residents arrived alone and in small knots to fill a meadow on a steep bank beneath the old Gold Star Brand Flour mill to gain a peek at the disaster area. Downstream, on the Skyway pedestrian bridge, University of Minnesota students leaned over cobwebbed railings, straining for a view.
James Janega and E.A. Torriero write for the Chicago Tribune. The Associated Press contributed to this article.