CBS 5 Investigates With Anna Werner

Diesel Tankers On Bay Bridge Spark Safety Worries

SAN FRANCISCO (CBS 5) ― Everyone in the Bay Area saw what a gasoline tanker fire could do to the MacArthur Maze, when a highway connector collapsed in April, 2007. One East Bay viewer asked CBS 5 to "Investigate This:" Why is he still seeing fuel tankers on the Bay Bridge?

Each day, as Steve Davies makes his commute into San Francisco over the Bay Bridge, he sees the sign that says "No flammable tank vehicles or explosives on the Bay Bridge."

It tells truck drivers they can't bring tankers with flammable liquids over the critical Bay Bridge span.

Yet on many weekdays, Davies also sees something else. "The fuel tankers have been going over the top of the Bay Bridge," he said.

Huge silver tankers carrying thousands of gallons of liquid, with placards on the side show a flame.

CBS 5 Investigates saw them too, truck after truck. So CBS 5 asked one of those truck drivers Gordon Branson, why he was driving on the bridge.

"It's diesel," Branson said, "you can cross the Bay Bridge with diesel."

Diesel fuel is widely regarded in the industry as safer than gasoline because it doesn't catch fire as easily. It's classified by Caltrans as a combustible while gasoline is classified as a flammable.

Why is diesel considered safer? Caltrans' Chief of Traffic Operations Robert Copp said, "My understanding of combustibles is that they don't catch on fire until over 100 degrees Fahrenheit, sometimes 130 sometimes 140, whereas flammable liquids will catch even below freezing."

The sign at the Bay Bridge toll plaza stops gasoline tankers but not diesel tankers. But that policy may be a problem. Why? Because multiple experts interviewed by CBS 5 Investigates say that given the right scenario, a diesel tanker fire could also cripple the Bay Bridge, one of the Bay Area's lifelines.

Charles Roush works for an Oregon company that does accident consulting and conducts safety training for trucking companies.

CBS 5 Investigates asked Roush, "Do you think they ought to be on this span?"

"No," Roush responded. "The short answer is they have no business being there at all."

Why? Because of accidents like one in Chicopee, Massachusetts in March of this year where a diesel tanker rolled over and split open on the highway and then caught on fire.

"Diesel is every bit as dangerous if not more dangerous than gasoline," Roush said. Especially, he said, when other vehicles are involved.

"The number one reason why you have a spill is because there's an automobile accident involved," Roush said. "You have a great chance for fire, and when there's a fire, that's plenty enough to get the diesel burning."

Once that fire starts, a noted bridge expert said it's a problem for the Bay Bridge.

"This bridge is vulnerable," said Abolhassan Astaneh, a professor of civil engineering at UC Berkeley. He said an intense diesel fire can rival the Maze fire when it comes to damage.

Astaneh said when comparing to the Maze fire, "If that heat was on the Bay Bridge, then the situation can be worse than MacArthur Maze."

Astaneh was a leading expert on the World Trade Center disaster and has studied the Bay Bridge for over a decade.

"When steel gets hot and exposed to fire too long then the strength comes down. You can call it any name you want, jet fuel, whatever," Astaneh said. "Tell me if it can burn enough, then, I can tell you that this is going to collapse."

He also believes because of the potential risks, those loads of diesel fuel shouldn't be on the bridge. "That bridge cannot tolerate it," Astaneh said.

It's something at least one elected official, Scott Haggerty of the Alameda County Board of Supervisors, agrees with.

"I don't think that anything that contains a hazard to the bridge or the bay below it should be on the bridge," Haggerty said.

CBS 5 Investigates asked Caltrans' Robert Copp to explain how Caltrans arrived at its determination to ban gasoline tankers but allow diesel tankers on the bridge. "Diesel particularly, I don't know of a study," Copp said. But after hearing about the experts' concerns, he told us Caltrans is interested in hearing more.

"If you've got some information, we'd be glad to look at it, safety is very important to us and we need to see that information," Copp told CBS 5 Investigates.

Caltrans officials also expect to get feedback on the fuels issue from a review conducted after the MacArthur Maze fire. That report is not yet complete.

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