Divers locate remains at bridge collapse site

MINNEAPOLIS -- Divers found more human remains in the Mississippi River yesterday, 11 days after a highway bridge collapsed into the fast-flowing water. A crane working at one end of the ruined span removed a school bus and other vehicles.

Navy divers searched for five people missing and presumed dead. Stormy weather made their task more dangerous over the weekend, strengthening river currents Saturday.

But conditions had cleared yesterday and the remains were recovered about eight hours into the search, the Hennepin County sheriff's office said. The official death toll stood at eight while the county's medical examiner identified the remains.

The bus was among 44 vehicles hoisted off the bridge, out of roughly 100 on the Interstate 35 west bridge when it fell Aug. 1, said Kevin Gutknecht, a spokesman for the Minnesota Department of Transportation. Most vehicles on the bridge's north end were gone; Gutknecht said work would focus on the south end for the next day or two.

The yellow school bus became a symbol of a disaster that could have been worse. Everyone on board -- 52 children and several adults -- survived.

Broken glass remained on a slanted section on the bridge's north end as pedestrians and cyclists peered through a mesh fence put up to keep them from getting too close.

Removal crews have cleared cars from parts of the bridge that fell onto land. They have equipment positioned to start major debris removal once the recovery efforts are finished.

Divers recovered three bodies Thursday and Friday.

About 100 people were injured in the collapse, but eight remained hospitalized, their conditions ranging from serious to good.

Investigators are looking into whether the collapse was caused by the failure of gussets, metal plates that hold girders together. The gussets on the Minneapolis bridge were attached with rivets instead of bolts used in more modern bridges.

Some engineers also have speculated that wear and tear from the heavy weight load on the bridge could be one of the factors that triggered the collapse.

In a decade, from 1995 to 2005, the weight load on urban highways increased by half. Since 1970, the weight carried on rural highways has gone up nearly 7 1/2 times, according to Federal Highway Administration statistics.

The number of tractor-trailer truck miles driven on American roadways has doubled to more than 145 billion miles a year since 1980, increasing faster than the rate of smaller trucks or cars, according to federal statistics.

"If we're doubling our loads, we need to look at our infrastructure to be able to carry that," said James Garrett, an infrastructure researcher at Carnegie Mellon University.

More weight wouldn't be a problem if the highway system were adequately maintained because well-kept roads and bridges can handle the added weight, said C. Michael Walton, a civil engineer professor at the University of Texas.

A 2006 Department of Transportation inspector general study checked 43 bridges in Massachusetts, New York, and Texas and found that at least 12 of them allowed vehicles to cross that were heavier than the bridge's maximum weight limit.

And 11 of those did not have the required posting signs.