COLUMN ONE : Caltrans’ Hard Jolt of Reality : The Bay Area earthquake exposed some critical flaws in the state’s seismic safety program. Retrofitting had proceeded at a snail’s pace--and in the wrong place.

California’s program to strengthen highway bridges against earthquakes has risen and fallen for 18 years like the earth’s crust in a major temblor, shaking violently into action with each major quake but never sustaining its energy over an extended period.

The effort, begun after the 1971 San Fernando Valley earthquake, has been thwarted by the tight-fisted budget policies of two governors--Edmund G. Brown Jr. and George Deukmejian--the unwillingness of governmental leaders to push earthquake projects once public interest in them waned and the political timidity of Caltrans engineers.

Although the state’s highway engineers have been considered the best in the nation, they placed a low priority on strengthening the Nimitz Freeway in Oakland, basing their judgment on lessons from earlier earthquakes in other parts of the state. The freeway’s collapse in the 7.1-magnitude Bay Area quake on Oct. 17 killed 42 people.

The quake exposed at least three critical flaws in the state’s seismic safety program, according to public documents and interviews with private and public engineers:

* Timing. Although they knew in 1971 that hundreds of bridges were prone to collapse in a severe quake, Caltrans engineers settled for an 18-year program to complete just the first phase of a plan to strengthen the structures. A second phase was in limbo until the 1987 Whittier quake, and what is now being called the third phase was not even on the schedule until October’s Bay Area disaster.

Now that the earthquake has focused renewed scientific and political energy on the vulnerability of the state’s freeways, Caltrans is prepared to spend hundreds of millions of dollars on a program for which it had earmarked just $64 million before the quake.

* Priority. The state concentrated its efforts on strengthening bridges similar in design to those damaged in the 1971 San Fernando Valley and 1987 Whittier temblors. There were no structures similar to the Nimitz Freeway within the Los Angeles quake zones. As a result, the state gave a low priority to the Nimitz and other, older structures in the Bay Area.

* Focus. State geologists have been saying for years that the soft soil around the filled-in portion of San Francisco Bay would mean trouble for all elevated highways in the area, and the latest scientific evaluations of the Nimitz collapse point to loose soil as a leading cause of the disaster. But Caltrans never considered soil types when it developed a priority list of bridges to be retrofitted.

“In retrospect, we see they didn’t have their priorities right,” said George Housner, chairman of Deukmejian’s commission investigating the Bay Area earthquake damage. He added that Caltrans was not entirely to blame, because it was acting on advice from engineers and geologists who expected the next major quake to strike Southern California rather than in the north.

‘Unacceptable’ Result

Thomas Tobin, executive director of the state Seismic Safety Commission, credited Caltrans for pioneering the retrofitting of existing highway structures. But he said the program, like other earthquake protection efforts in California, was insufficient and “without question too slow.”

“Our program,” he said, “was so inadequate as to be almost non-existent. That’s unacceptable.”

Caltrans officials acknowledge that their program had flaws.

“From every earthquake we are going to learn something new,” said James Gates, chief of structural and seismic analysis for Caltrans. “We haven’t learned it all yet. And in the next earthquake we’re going to learn something else.”

But Gates and others in the department insist that without a significant financial commitment from the state, the mammoth task of uncovering and correcting potential defects in thousands of bridges can only move at a snail’s pace.

Hoping that nature would give them enough time to fix the worst problems, they say they determined their top priority would be to retrofit those bridges nearest to active faults with the most glaring vulnerabilities.

From the San Fernando quake they concluded that the most pressing problem was the design of the road decks of pre-1971 bridges, which tended to slide off the top of their columns when subjected to strong ground shaking. The engineers designed the first phase of the earthquake retrofitting program to fix the problem by installing steel rods and cables to tie the sections together and prevent sway.

Gates and James Roberts, chief of the department’s structures division, say that the two major temblors that followed the San Fernando quake, in Whittier and now in the Bay Area, generally proved their priorities to be correct. Had the decks of dozens of bridges in the disaster areas not been tied down, the Cypress Viaduct on the Nimitz Freeway would have been just one of many bridges to collapse, they said.

“I’m convinced that there were over 100 lives saved because of (that tie-down) program,” Gates said.

For the engineers, the San Fernando quake had been cataclysmic. In a few short seconds on the morning of Feb. 9, 1971, the earth taught them that what they considered state-of-the-art design standards for seismic safety were grossly inadequate.

The quake, registering magnitude 6.4 and centered beneath Sylmar, caused the collapse of three freeway viaduct sections and two interchanges, including the newly completed but still unopened interchange at Interstates 210 and 5. Miraculously, only two men driving to work in a pickup truck were killed. But the damage told the smartest engineering minds of the day not only that what they had been doing in the past was wrong, but what they planned for the future was insufficient.

A young engineer at the time, Gates remembers that the earthquake set off feverish activity in the Caltrans engineering department. What was wrong? How could they fix it? Hurry, hurry, hurry before the next one hit and the death toll soared.

Revival Meeting

“It was just like a revival meeting,” he recalled. “There was just a thirst. What can we do to make it better? What can we change? Digging all over. We had slide shows. Day after day we would look at these slides and look at these damage pictures.”

But the engineers’ enthusiasm was not always matched by state policy makers and high-level Caltrans officials.

While there is no evidence that Deukmejian or Brown ever sought directly to curtail earthquake safety measures, both administrations took actions that indirectly limited the ability of the engineers to get the job done.

The most severe of these actions, by all accounts, was the massive layoff of Caltrans engineers at the onset of the Brown Administration in the mid-1970s. The cutback, which actually began in 1974 when Ronald Reagan was governor, was caused partly by a shortage of gasoline tax revenue resulting from the Arab oil embargo, which decreased fuel consumption. And, in part, the retrenchment was due to the end of a long boom in federal highway construction.

But much of it was the result of Brown’s “small is better” approach to government, under which he and former state Transportation Director Adriana Gianturco promoted mass transit and de-emphasized freeways. Gianturco maintains that the Administration’s opposition to new freeways never shortchanged the maintenance of existing roads, or programs such as the seismic safety endeavor.

“Every dime that was ever requested, I approved,” Gianturco said in a recent interview.

But others, including the man who was running the retrofit program at the time, say the layoffs gutted the program of its best and brightest minds just as it was getting off the ground. In all, roughly 1,800 of the department’s 5,000 engineers were let go during the 1970s, according to Caltrans officials.

“That had a hell of an impact on the department,” said Oris Degenkolb, a retired design engineer. “It took everybody out who had up to 10 or 15 years experience with the department. They were real hot on computers, dynamics, the stuff that had just been developed. Some of us old-timers had not gotten around to getting into that.”

Deukmejian was sharply critical of Brown’s approach to highway building and pledged when elected in 1982 to restore the program. Still, his Administration’s first-term goal of reducing the number of state government employees did not spare Caltrans.

Employee Cutbacks

Although about 1,000 of the engineering jobs had been restored with revenue from a 2-cent increase in the gasoline tax Brown signed into law as he was leaving office, the Deukmejian Administration cut the force by nearly 400 engineers between 1984 and 1987, Caltrans records show. Department memos show that there was great pressure on supervisors to keep the number of employees to a minimum.

Only recently, with the help of money from sales tax measures passed by voters in some counties, has the number of engineers begun to climb again. This year, Caltrans has authorization for 6,720 engineers.

Engineers, however, say that over the years the numbers were not as important as the belt-tightening mentality, which created a sort of “chilling effect” on their funding requests. They say they lived within the limits imposed on them from above, muttering among themselves about the lack of support but never raising the issue with the Legislature and the press.

Internally, Roberts said, the engineers in the earthquake-strengthening program were vying with other programs.

“We were fighting for our share of the traffic safety program and there were people (who) said the statistics were far more supportive of median barriers and other kinds of traffic safety” devices, Roberts said. “Up until this earthquake we had had two deaths on the state highway system as a result of earthquakes.”

Assembly Transportation Committee Chairman Richard Katz (D-Sylmar) said he believes that the engineers fell victim to an attitude typical of bureaucracies: “They’re too willing to accept the answer of ‘We can do it tomorrow if we don’t do it today.’

“And if you’ve gone through Caltrans under eight years of Jerry Brown and gotten your brains beaten in pretty bad, and then Deukmejian’s early signals were that it’s not going to be much different in terms of more staff for engineering or more money for roads, my guess is that after eight, 10, 12 years of that, you decide, ‘What’s the point?’ ”

But the flow of money does not tell the entire story. There also were engineering judgments that, in retrospect, appear to have been flawed. At some point during the early 1980s, for example, top engineers in the department decided that the columns supporting elevated structures did not need strengthening.

In 1985, Ray J. Zelinski, who was heading the retrofit program, said the first phase of the program--tying the roadbeds together--would be sufficient to protect every elevated structure in the state. Any further work would be dictated by reviewing the “behavior of retrofitted bridges during earthquakes.” In other words, the state would wait until the next earthquake and see if any bridges fell.

That same year, Roberts returned to the structures division from another assignment in the department and decided, despite Zelinski’s pronouncement, that the retrofitting program needed to be revitalized. He said he was immediately warned that the cost estimates on the program were “pretty high,” but he ordered that the project proceed anyway.

The department was preparing to do research for the next phase of the retrofitting program when the state was rocked by another earthquake on Oct. 1, 1987. This time the quake, centered near Whittier, caused severe damage to a major freeway overpass--the Interstate 5/605 interchange--which, according to a paper authored later by engineering professor Nigel Priestly of UC San Diego, came “perilously close to collapse.”

Although there were no deaths on the freeway separator, the quake sent new shock waves through Caltrans. It had struck just as morning rush-hour traffic was at its peak, moving bumper to bumper across the overpass. “It is estimated that if the damaged section had collapsed, between 70 and 100 cars would have fallen with the bridge or been crushed underneath,” Priestly wrote.

The lesson from Whittier was that deck tie-downs were not enough. The engineers reasoned that the structure was still standing only because it was supported by multiple columns. If it had been a single-column bridge, it most certainly would have collapsed, they theorized.

Their conclusions prompted a frantic search for single-column structures built before 1971 and now considered the most vulnerable to earthquake damage. The plan to strengthen those bridges came to be known as the second phase of the retrofit program.

“Whittier, of course, gave us some cannon fodder to argue” for more funds, Roberts said.

Even with the new fervor, Caltrans had planned to spend $64 million on the second phase over four years and had not yet budgeted anything for multiple-column structures such as the Nimitz. But since the Bay Area quake, department officials have said they expect to have $55 million worth of work out to bid by next June and will spend “hundreds of millions” of dollars in the next five years. Katz believes that the tab, including the cost of local bridges, will eventually reach $1 billion.

“What we’ve learned so far from the San Francisco earthquake is that obviously retrofitting can’t go at that pace that was being funded,” Roberts said. “It’s got to go faster. We knew what was wrong and we were working on it, but obviously not fast enough.”

The pace, in fact, was so slow that the engineers only four months ago began to focus on the peculiar design of the columns supporting three San Francisco freeways: the Embarcadero, the China Basin portion of Interstate 280 and the Central Viaduct on U.S. 101. A team of academic and private engineers zeroed in on what they believed was a weak link: the joints connecting the upper and lower columns of the double-deck structures. Now there is near unanimity that the same design detail doomed the Nimitz.

The pace of retrofitting might have been faster if the Transportation Department, in setting its priorities, had considered a key factor: the soil underneath its highway structures.

Geologists have known for years that structures built on soft soils are more vulnerable than those built on rock or hard sediment. The softer soil tends to amplify the ground shaking and worsen the structural damage.

A 1982 report by the state Division of Mines and Geology forecast that, in a severe quake, the hardest-hit highways would be those built “along the margins” of San Francisco Bay. In a magnitude 8.3 quake on the San Andreas, the division said, the elevated section of I-880 through downtown Oakland “is expected to be extensively damaged.”

The Cypress Viaduct portion of the Nimitz, being more than a mile long, actually stretched over two distinct kinds of soil structures. The part that collapsed was built on pilings driven 50 to 60 feet through soft soil into hard sand. The portion that remained standing was built on land where the hard ground was just 10 feet beneath the surface.

Another overpass built on loose soil, the Struve Slough Bridge on U.S. 101 near Watsonville, also was ruined in the quake. In that case, the soil gave way and, while the bridge deck stayed in place, several support columns rotated like spoons “in a bowl of dough,” snapping away from the road deck, Roberts said.

But before Oct. 17, Caltrans had never seen a bridge collapse because of soil problems, so soil was not even considered when engineers established a priority list for bridges to be retrofitted. That surprised some experts.

“It’s been known for a long time that soil has a major impact on structures,” said Stephen Mahin, a professor of civil engineering at UC Berkeley who has helped Caltrans review some of its retrofit plans. “That should have been taken into account in the ranking of bridges.”

Caltrans did recognize the importance of the soil factor at least three years ago, but it was not something the department believed was important enough to assign to a full-time employee. Instead, Gates said, student interns were “whittling away” for three summers on the job of compiling the soil profiles for every bridge in the state.

Had that inventory been completed, Gates said, roadways built on soft soils would have been given a higher priority for retrofitting. “Cypress would have popped right to the top,” he added.

In essence, then, the Oct. 17 quake taught Caltrans that double-decked structures built on soft soil are extremely vulnerable. And, as it has after other earthquakes, the state now is focusing on how to strengthen those kinds of freeways that suffered the most damage. But there are only a handful of highways with that design, all in San Francisco, and while the engineers study that problem, it is possible that some other hidden design flaw awaits discovery in the next big quake.

Ultimately, no engineer can guarantee that motorists will be safe on every freeway in every quake. There are too many unknowns for such bravado.

With 26,000 highway bridges in the state, Gates pointed out, “how can you tell which one of these is going to break in the next earthquake? How do you do that? How do you find a Cypress?”