The collapse Wednesday night of the I-35W bridge in Minneapolis brought back vivid memories of a southern Ohio bridge tragedy 40 years ago for E.V. Clarke, and not just because of similar route numbers.

Mr. Clarke, now 76, who crossed the Ohio River twice each day to commute to work at a plastics plant in West Virginia, estimates he had been off the U.S. 35 Silver Bridge for less than a minute when it suddenly dropped into the river, taking two dozen cars and trucks into the water and another seven onto the Ohio shore below.

When I saw that thing in Minnesota, it all came back immediately, Mr. Clarke said Friday. That bridge was built the same year ours fell, and it had the same number, 35. It certainly shook me up and brought me back.

Forty-six people died in the 1967 bridge collapse, which touched off nationwide reviews of bridge design and inspection practices.

Design rethinking came too late, however, for the I-35W span, which was designed in accordance with American Association of State Highway Officials standards issued in 1961.

More modern bridges, including Toledo s new Veterans Glass City Skyway, are designed with redundant structures so that if one major component fails, others can assume the extra load and not also give way, as occurred with the Silver Bridge.

You could take a whole stay cable out of service, and the structure would maintain its integrity, said Mike Gramza, the project engineer for the I-280 bridge in Toledo, which opened to traffic June 24.

Citing security concerns, Mr. Gramza declined to say what degree of damage might bring the Skyway down, but he said that heavy equipment used to build the new bridge subjected parts of it to pressures unlikely ever to be exerted by traffic and that the concrete bridge components also were designed with redundancy in mind.

The lack of such redundancy in the truss-work supporting the I-35W bridge was among concerns raised in engineering reports about the structure in recent years.

Whether the I-35W bridge s structural design played a role in its collapse remains to be determined, and the National Transportation Safety Board estimates it will take a year to complete an investigation.

It took the safety board three years to adopt a report on the Silver Bridge collapse, which was blamed on the failure of a single link in a suspension chain just west of a bridge tower near the Ohio s west bank. When the link failed, other suspension chains could not handle the additional load and the bridge quickly tumbled into the river.

The safety board determined that the flaw in the chain could not have been seen by an inspector, nor would any other inspection method known at the time have revealed it unless the affected joint was disassembled.

The stress corrosion and corrosion fatigue that caused the flaw were unknown phenomena for the type of bridge involved at the time it was built, according to the NTSB report. Other reports noted that typical vehicle weights had tripled during the structure s life span.

The bridge linking Kanauga, Ohio, with Point Pleasant, W.Va., had stood for 39 years when it collapsed at about 5 p.m. on Dec. 15, 1967.

Mr. Clarke recalled checking his wristwatch when he arrived at his home in nearby Gallipolis, Ohio, at the end of his evening commute from what was then a Goodyear Tire & Rubber Co. polyester factory in Apple Grove, W.Va. When he heard about the collapse, he remembered the time he had seen on his watch and made a quick calculation.

I was off of it for maybe less than a minute before it collapsed, he said.

William Jenkins, now the city manager for Gallipolis but at the time the operator of a ready-mix concrete business along the river about a mile downstream, said his first evidence of trouble was a succession of emergency vehicles speeding by his business with sirens wailing.

I called the dispatcher at the police desk, and he said, They re telling me the Silver Bridge fell, said Mr. Jenkins, who was 30 at the time.

Like many others, Mr. Jenkins and a co-worker drove toward the bridge to see for themselves and provide assistance.

We kept looking up and there was nothing to see, he said.

About 400 yards before Mr. Jenkins got to the bridge site, he turned onto a road that led to the river.

From there, wreckage, including tractor-trailer rigs, could be seen floating downstream. Another bystander spotted a body and swam out 100 feet to attempt a rescue, but the victim, a woman, was dead from a traumatic injury.

Mr. Jenkins said he knew several people who died in the Silver Bridge collapse and several others who survived. The City Ice and Fuel boat, which delivered fuel and provisions to Ohio River tugboats, got all the people that came up out of the water between four and six, he said.

Mr. Clarke, meanwhile, recounted that two other deaths indirectly attributable to the bridge collapse occurred about two months later.

Some of the Goodyear plant s Ohio work force took to using small boats to cross the river, and one February night a boat carrying four of them home after the evening shift capsized, he said.

While all were wearing life jackets, one couldn t swim, and he and another man who stayed with him were swept downriver and froze to death in the icy water. The bodies were found 25 miles away in Huntington, W.Va., the next morning.

A replacement U.S. 35 crossing of the Ohio, the Silver Memorial Bridge, opened downstream in 1969 and remains in use.

The deadliest U.S. bridge collapse since then was that of a viaduct along I-880 in Oakland, Calif., during the Loma Prieta earthquake in 1989.

Forty people died when the double-decked Cypress Street Viaduct fell, crushing vehicles on the lower deck.

Others of potentially greater relevance to the I-35W bridge collapse in Minneapolis, include the June 28, 1983, collapse of a 100-foot bridge section on I-95 over the Mianus River in Greenwich, Conn. It killed three motorists and injured three others.

On April 5, 1987, several spans of a bridge carrying I-90 over Schoharie Creek near Amsterdam, N.Y., collapsed, killing 10.

Investigators blamed inadequate inspections and maintenance for the Connecticut accident, which was traced to corrosion in a pin-and-hanger assembly that supported the fallen bridge section.

The New York collapse was caused by underwater scouring that removed soil from beneath a bridge pier, especially during flood conditions, leading eventually to the pier s collapse.

Contact David Patch at:dpatch@theblade.comor 419-724-6094.

First Published August 5, 2007, 12:10 p.m.