Bay Bridge Replacement: 1860' self-anchored suspension bridge [Archive]

BTinSF

Jan 20, 2008, 8:35 AM

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Bay Bridge's single-tower span gets off ground
Michael Cabanatuan, Chronicle Staff Writer
Sunday, January 20, 2008
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The Bay Area will finally get a chance to see what it's long been waiting for - the construction of a soaring single-tower suspension bridge east of Yerba Buena Island.

After a decade of controversy, politics and delays, and six years after construction started on the $5.5 billion new east span of the Bay Bridge, the 1.2-mile concrete skyway is a few steel plates and some paint from completion, and foundations for the bridge tower and suspension span are scheduled to be finished by Tuesday.

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Even the complex work to replace the San Francisco approach to the bridge is nearing an end.

Now the attention turns to construction of the single-tower suspension span.

The suspension span "will be in final gear after all this waiting," said Bart Ney, a Caltrans spokesman. "We're out of the water, and out of the ground. It's all aerial acrobatics from here on out."

For the next five years, if everything goes according to schedule, workers for a joint venture of American Bridge and Fluor Corp. will assemble a 1,860-foot steel bridge that will be painted white and suspended on a single cable from a 525-foot tower.

It will rise just east of Yerba Buena Island, serving as a visual exclamation point at the end of the long, slender concrete skyway.

Often referred to as the "signature span," the bridge will be the first large self-anchored suspension bridge ever built - and it's destined to become a new Bay Area landmark. But construction will be long and complicated.

"This is the first one," said Mike Flowers, a veteran bridge engineer and American Bridge spokesman. "It's a lifetime opportunity. We've got quite a few young, bright, talented engineers working out here, and in five, six years, when we're done here and they move on to other projects, it's going to be kind of a letdown."

Work on the suspension span has already started, but much of it has been confined to trailers at the Port of Oakland or Yerba Buena Island, where a massive construction platform has been erected atop the western foundation for the suspension span.

Within a couple of months, motorists will see steel trusses begin to reach east, where they will connect to the skyway.

"We pretty much have to build two temporary bridges to build the permanent bridge," Flowers said.

Those side-by-side bridges will never carry traffic. Instead, they'll serve, along with six temporary towers, as interim supports to hold the 28 winglike steel deck pieces that will make up the new bridge deck - 14 segments for eastbound lanes and 14 for westbound.

Those sections will begin arriving by ship from Shanghai, where the bridge is being manufactured, in October or November. Steel sections of the tower will arrive by early 2009.

Over the next few years, crews will erect the tower, assemble the suspension cable and stretch it over the tower and beneath the bridge, and attach it to the deck. Then the temporary supports will be removed - and the bridge, it is hoped and expected, will support itself.

"As they say, you ain't seen nothing yet," Flowers said.

So far, most of the construction has taken part on the east side of the bay, where a joint venture of the Kiewit, FCI and Manson firms built the twin concrete viaducts known as the skyway. While they've been described by detractors as freeway on-ramps on steroids, they seem graceful from the water, rising from the eastern shoreline and curving toward Yerba Buena Island.

Built for $1.04 billion, the skyway rose out of the bay even as the debate raged in 2004 and 2005 over whether to scrap the single-tower design - and who should foot the bill for the bridge's huge cost overruns.

The foundations for the suspension span sit in the bay between Yerba Buena and the stub end of the skyway, which looms 150 feet above the water. The tower foundation is a big concrete octagon with a small forest of steel posts sticking out of the top. The steel tower, which will be lifted into place in four pieces, will be anchored to the steel pins.

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Below the concrete, 13 piles with a diameter of 10 feet reach down 200 feet into bedrock. The eastern foundation features two concrete towers, 120 feet tall. It's anchored to the bay floor with 16 pilings 81/2 feet in diameter driven 300 feet deep into the hardened mud.

The foundation work is being completed about 80 days early, which means KFM will earn a $5 million bonus, making the total cost of the marine foundation work $280 million - $33.5 million under budget. The early finish is allowing American Bridge to start its work sooner, Ney said, which could be crucial given the complexity of the work ahead.

Among the twists and turns awaiting motorists is the temporary bypass that is being built to the south of the existing bridge. Support columns have been built, and contractor C.C. Myers' crews are just starting the deck.

The final piece of double deck will be lifted into place during a full bridge closure sometime in the spring of 2009, Ney said. Until 2012 or 2013, the double-deck bypass will carry cars from the end of the trestle section of the bridge and loop slightly around the existing connection to the Yerba Buena tunnels. The detour, which will probably have a reduced speed limit, is needed to allow workers to build a link to the tunnels for the new bridge.

But there is some good news ahead for drivers. The reconstruction of the San Francisco approach to the bridge, which required a series of lane shifts, regular lane and ramp closures and one partial bridge closure, is almost done. Crews were pouring concrete last week for the permanent eastbound approach, which Caltrans tentatively expects to open by April.

After the eastbound opening, a couple more months of work will remain, and the Harrison Street off-ramp will still be closed, Ney said, but no more traffic shifts will be necessary.

While that work is winding down, American Bridge crews are gearing up across the bay in Oakland.

On Thursday, crews were preparing to test a cable-compression device, which will crunch together 17,400 5-millimeter wires, gathered into 137 strands, after the cable is strung. The test will take place Monday, but Ney is already thinking ahead to 2013.

"This is something we will keep for a museum," he said, "or display at the entrance to the bridge."

nline resources:

ay bridge project information:

www.baybridgeinfo.org

E-mail Michael Cabanatuan at mcabanatuan@sfchronicle.com.

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BTinSF

Jan 20, 2008, 10:13 PM

^^^Does this help?

TOWERING QUESTION -- WILL IT FINALLY BE BUILT?
Planners hope the Bay Bridge's new eastern span, beset by political squabbles since the 1989 earthquake, has cleared its final hurdle

John King, Chronicle Urban Design Writer
Tuesday, March 21, 2006
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When state officials open construction bids on Wednesday to build the tower for the new eastern half of the Bay Bridge, the target date to finish work will be 2013 -- 24 years after the Loma Prieta earthquake snapped the upper deck apart.

Instead of an earthquake-proof bridge ready for traffic in 2004 as first promised, what exists today is a half-finished project that stands as a symbol of the Bay Area's political inability to come together as a region even when lives and livelihoods are at risk.

There's no way to recapture the years lost when Bay Area leaders failed to put aside their own agendas in order to construct a safe bridge that carries 280,000 vehicles a day. Those delays also are part of the reason the project's estimated cost has more than quadrupled to $6.3 billion.

In the meantime, the most important highway in the region still depends on a bridge that has been strengthened to withstand the sort of temblor that closed it for a month in 1989 -- but nothing more severe.

"We had a hard time from the get-go trying to focus people on the need for speed, that this was a matter of seismic safety," said Steve Heminger, executive director of the Metropolitan Transportation Commission. "I don't think we ever made that sale."

When a magnitude 7.1 temblor struck the Bay Area on Oct. 17, 1989, the western half of the Bay Bridge, a brawny suspension bridge with four towers that march toward San Francisco from Yerba Buena Island, rode out the earthquake with little damage.

But the eastern half that lifts off from the mudflats of Oakland -- a trussed structure that resembles an enormous erector set -- had its seismic limitations exposed with deadly force. A 50-foot section of the upper deck collapsed onto the deck below. Two cars plunged into the chasm, and one driver was killed.

Though the bridge reopened in a month, six years passed before the California Department of Transportation decided that the eastern span should be replaced. First came the challenge of trying to find ways to retrofit a complicated 60-year-old structure. Top advisers to then-Gov. Pete Wilson, a Republican from San Diego, were wary of wading into the contentious thicket of Bay Area politics.

"They figured all of us in the Bay Area painted our faces blue at night and climbed trees," one engineer recalled with a laugh.

Eventually, Wilson and his advisers agreed with engineers that a new bridge was the way to go. It was with fanfare that Caltrans in February 1997 introduced the span it wanted to build: a utilitarian viaduct that would cost roughly $1 billion and could be ready for traffic by 2004.

Another bridge was shown that day, one with cables fanning down from a tower to the deck. But such a flourish would add at least $200 million to the project -- and the state made clear who would pay.

"If the residents of the Bay Area desire an aesthetically enhanced bridge," Wilson told reporters, "the additional cost should be borne by the Bay Area."

Bay Area politicians agreed to raise tolls for a so-called signature tower, but they upped the ante: They wanted to select a design on their own. Caltrans granted the request as long as the decision was made by July.

Decision-making power was handed to the Metropolitan Transportation Commission, which consists of elected officials from around the Bay Area and controls the region's transportation money. The commission promptly appointed a task force; the task force promptly assembled a panel of engineers and architects to provide technical guidance.

Then came the hard part.

Public attention focused on what the bridge should look like and whether it should have a bike lane. The thorniest issue, though, was the location of the new span.

It could run slightly south of the existing structure, but that would require land needed by the thriving Port of Oakland. Or it could run slightly to the north -- and crowd a cluster of historic buildings the Navy owned on Yerba Buena Island.

By July, the task force and panel had held 14 public meetings and made several key decisions. The span would be a viaduct across the muddy shallows near Oakland. Visual oomph would be provided by a tower over the deeper water near Yerba Buena Island. And it would follow the path known as the northern alignment.

But Caltrans didn't get what it asked for: an actual design.

Instead, the advisory panel asked Caltrans to perform design work on several different bridge types so it could evaluate the construction feasibility and seismic strength.

Caltrans dutifully hired consultants and returned eight months later with six different schemes. The panel whittled down the options until two remained, each featuring a tower rising like a flagpole between the eastbound and westbound decks.

One was a cable-stayed bridge, the type the state had proposed to begin with. The other was a self-anchored suspension bridge.

The self-anchored structure is similar to a traditional suspension bridge, in which the roadway hangs from a pair of cables suspended between towers. But instead of burying the ends of the cables into anchorages, a self-anchored suspension bridge folds them into its deck.

As the advisory panel second- and third-guessed each aspect of the design, seismic issues seemed far away.

"A lot of the focus on the panel was the idea of a signature span -- 'Let's get this big, significant thing done,' '' said Christopher Arnold, a Palo Alto architect on the panel.

"If the engineers had been more insistent about engineering, things might have been different. But they would mumble something, and then the architects would swing back to aesthetics."

With one meeting left to go, the cable-stayed bridge was favored.

So on the weekend before the final advisory-panel meeting in May 1998, the designers working on the suspension bridge repackaged their design -- moving the tower closer to the island to create an asymmetrical silhouette. They also moved the main cable so that it would loop underneath the deck near the island, an innovation that has never been tried.

The design was a major change and lacked the engineering details that the panel had insisted on 10 months earlier. But the unique appearance carried the day. By a 12-7 vote, the panel selected the suspension bridge.

"We all felt it was a challenging design -- it is -- but it can be done," said Joseph Nicoletti, an engineer who co-chaired the panel. "That's what makes it interesting to engineers."

Arnold backed the cable-stayed design. "The novelty factor kicked in, especially with the engineers," he said of the final vote. "And everyone was getting a bit tired by then."

The Metropolitan Transportation Commission made the choice official in June 1998, 15 months after the first task-force meeting. To make up for lost time, Caltrans set an ambitious schedule: Construction would begin in 2000, and opening day was set for 2004. The estimated cost: $1.4 billion.

The lone "no" vote came from Oakland Mayor Elihu Harris, who was unhappy that the entrance to Oakland would be a marked by a viaduct rather than a tower.

San Francisco's two members abstained -- an ominous hint of what lay ahead.

It was at this point that the region's need for a seismically safe bridge confronted the hard fact of life that all politics are local.

In the Bay Area of the 1990s, nobody played hardball politics better than Mayor Willie Brown of San Francisco.

The mayor's stance on the bridge was no secret: Work on the eastern span should include projects tied to Brown's plans for his city. Most important, Brown wanted new ramps linking the bridge to Yerba Buena Island and Treasure Island, which the U.S. Navy was transferring to city ownership.

But as the selection process moved forward, San Francisco received little in the way of concessions. The tight ramps from Treasure Island onto the bridge remained, for instance, because Caltrans saw them as something other than a seismic problem.

Brown saw a slap in the civic face -- and prime development sites imperiled by outsiders.

"Our representatives were essentially losing every battle," Brown said recently. "There was clearly an indifference to any San Francisco consideration. How could you design a bridge that wiped out ingress and egress for a new neighborhood?"

Though Brown earlier had endorsed the northern alignment, he now said it wasn't acceptable. And he wasn't the only disgruntled politician: East Bay leaders chimed in with their own complaints.

In Oakland, the mayor-elect, Jerry Brown, called for an international competition to produce "a structure that people seek out from all over the world."

Oakland Assemblyman Don Perata called for a regional election on a design that he said was "about as popular as New Coke."

The mayors of Emeryville and Berkeley demanded that the design be changed to include room for commuter trains.

But Willie Brown had one tactical advantage his East Bay allies lacked: the aggressive support of the Navy.

Naval officials, supporting Willie Brown's position that a northern alignment would intrude on the former military base, took the position that state engineers could not enter Yerba Buena Island to collect soil samples or do site surveys. As long as this was the case, design work on the tower could not begin.

On one occasion, naval officials called Caltrans to order a boat filled with engineers out of Navy waters. Meanwhile, Willie Brown's point person for the islands was taking regional officials on tours of the island in a golf cart, pointing out the supposed perils of the northern alignment.

As far as Brown is concerned, he and the Navy were simply protecting their interests.

"They were totally indifferent to the owners of the property," Brown said of Caltrans and regional officials. "I probably wouldn't have paid any attention to anything other than getting the bridge built ... if the plans had been friendly to Treasure Island."

Robert Pirie, former assistant secretary of the Navy, now suggests the Navy was taking its cues from the San Francisco mayor.

"Our guidance at the time was to help the local authorities as much as possible," Pirie said this month. "It was a dispute between the city and county of San Francisco -- Willie Brown, mainly -- and Caltrans, and we were in the middle."

When Gray Davis became governor in January 1999, the official design appeared doomed. Davis had been Jerry Brown's chief of staff when Brown was governor in the late '70s. More recently, Willie Brown was the most influential politician to endorse Davis when his gubernatorial bid seemed a longshot.

Known for taking a cautious approach to controversial issues, Davis was in no rush to take a stand. But in March, he brushed off his allies' pleas: "It's been 10 years since the earthquake, and we need to fix the bridge."

As for complaints about the design, Davis agreed something grander would be nice. On the other hand, he said, "it would be nice if it rained beer, too."

That should have ended the story: A new governor had ratified the outcome of a long public process.
Instead, the battle shifted to Washington, D.C. For the rest of 1999 and into 2000, Willie Brown and Davis pressed their cases before the Clinton administration. While one sought to block the plan, the other looked for ways to outflank the Navy. And White House staffers found themselves trying to make sense of a struggle rooted in engineering and economics 2,500 miles away.

"It was like a pendulum swinging back and forth," recalled Karen Skelton, who handled California issues for President Bill Clinton. "On one side, you had issues involving architecture, historic preservation, economic development ... on the other side was safety."

As his push to move the span stalled, Brown changed course. He called for a retrofit of the existing bridge instead of building a new one. And he added safety to his issues by seizing on one expert's claim that the approved tower was inherently unstable.

The warnings came from Abolhassan Astaneh-Asl, a UC Berkeley engineering professor. In 1997, when the search began for a new design, Astaneh attracted attention as part of a team proposing a sail-like tower. The proposal was rejected.

Now he insisted that because the self-anchored bridge's cable lacked a conventional anchorage, any severe jolt might cause it to collapse.

Caltrans dismisses Astaneh's thesis, as do seismic engineering experts. But Brown met with Astaneh and gravely pronounced the professor's claims "frightening, really frightening."

He also arranged a Washington meeting at which Astaneh could present his scenario to federal officials.

Meanwhile, Davis' staff and Caltrans engineers made the Beltway rounds looking for support. But California's congressional delegation showed no desire to intervene in what from afar looked like a dispute between the top-ranked Democrat in the state and the renowned power-broker whom the president himself once had dubbed "the real Slick Willie."

Sen. Dianne Feinstein was seen as the one state figure with the stature to break the impasse. She was lobbied by both sides -- and then called for studies of an additional bridge from the East Bay that could serve drivers headed south of San Francisco.

Nor were members of the congressional delegation, including Sens. Feinstein and Barbara Boxer, trying to smooth things out behind the scenes. "I had absolutely zero interaction with Boxer or Feinstein on the subject," Pirie recalled, "or any congressional representative."

What finally dislodged the impasse was a legal move by the federal Department of Transportation.

Skelton left the White House to become chief counsel for Transportation Secretary Rodney Slater. There, she learned that the department could seize other agencies' land to make improvements to the nation's highway system.

The Bay Bridge is part of Interstate 80.

"It was a dusty old law," said Skelton, now a political consultant, "but it was still on the books for a purpose."

In the summer of 2000, the White House approved the transfer of land on Yerba Buena Island from the Navy to the highway administration so seismic work could be done on I-80 where it crosses San Francisco Bay.

Brown is now philosophical about the outcome. "At that stage of the game, we had played our hand out."

When the suspension bridge design was chosen in 1998, engineers planned to start on the tower first. That way it would be finished at the same time as the viaduct, which is easier to build.

Instead, the impasse that kept engineers off Yerba Buena Island forced Caltrans to begin the viaduct first. This would have extended the construction schedule by two years even if everything else had gone as planned.

They didn't. The delays of the late '90s pushed the project into a much different environment than the one in which it was conceived.

The terrorists who destroyed the World Trade Center on Sept. 11, 2001, made it difficult and pricey to insure high-profile projects such as bridges.

A prolonged construction boom in Asia caused the price of steel and concrete to soar. In the United States, other public works projects moved into line ahead of the Bay Bridge.

The unstated assumption of the eastern span saga -- that the world would wait for the Bay Area to make up its mind and resolve its disputes -- was proved wrong.

The latest delays came after the state invited contractors to compete to build the signature tower; the complex design and boom times elsewhere help explain why only one bidder stepped forward. And the lone bid in 2004 was $1.8 billion -- more than twice the budgeted amount.

Gov. Arnold Schwarzenegger halted work on the foundation and called for a simpler design, but a funding compromise with the state Legislature last summer allowed the tower to proceed.

State officials hope that this will be the last substantial hurdle and that the new span will open in 2013. The projected price: $6.3 billion, nearly $5 billion above the 1998 estimate.

In the meantime, a major earthquake on either the San Andreas Fault or the Hayward Fault grows closer by the day. The only question is when it will occur -- and whether the cost of the delays on the Bay Bridge will be measured in dollars or lives.

Bay Bridge timeline
1936: Bay Bridge opens. The upper deck is for automobiles, the lower deck for trains. Daily traffic is 21,000 vehicles.

1958: Train tracks are removed from bridge, clearing both decks for cars. Daily traffic is 53,000 vehicles.

Oct. 17, 1989: Loma Prieta earthquake snaps a section of the eastern span, killing one driver. Bridge is repaired within a month. Daily traffic is 286,000 vehicles.

December 1996: A panel of seismic experts concludes the eastern span should be replaced rather than retrofitted.

February 1997: Gov. Pete Wilson administration announces it wants to build an elevated skyway from Oakland to Yerba Buena Island that can be ready in seven years if everything goes smoothly. The administration also offers to build a more distinctive cable-stayed bridge if the Bay Area is willing to pay the extra cost. In either event, says Caltrans Director James W. van Loben Sels, "we must move ahead quickly on a solution that ensures the motoring public's safety."

March 18, 1997: The first meeting of the Bay Bridge Design Task Force takes place. The task force was created to select the design that Bay Area elected officials have agreed to finance through higher tolls on local bridges. It consists of six elected officials and one member of the San Francisco Bay Conservation and Development Commission. It is led by Alameda County Supervisor Mary King, who says her job is "to develop a consensus recommendation on a design option" -- in other words, "chocolate fudge on top of the vanilla ice cream bridge that the governor guaranteed us."

July 1997: Mayor Willie Brown of San Francisco writes King, stating that he supports placing the new span north of the existing bridge because "the economic development opportunities to the Port of Oakland outweigh the economic opportunities to San Francisco at Yerba Buena Island."

The Metropolitan Transportation Commission sends 17 recommendations to Caltrans. One recommendation: Delay choice of a design until Caltrans takes several bridge schemes to "approximately the 30 percent design stage so that reliable information as to seismic performance, cost, visual design and other issues can be obtained."

May 1998: Advisory panel of engineers and architects recommends a suspension bridge with five lanes of traffic hanging from each side of a 525-foot tower. The panel also recommends a 12-foot-wide lane for pedestrians and bicycles -- the result of a tenacious lobbying campaign by bicycle advocates.

June 1998: Ten East Bay elected officials send a letter to King complaining that the task force "has not produced a world-class design that establishes a sense of gateway and place for the East Bay."

Mayor-elect Jerry Brown of Oakland makes the same complaint in a Chronicle opinion piece, saying the approved design "speaks of mediocrity, not greatness. ... We must create a spectacular structure that expresses the daring of human ingenuity and symbolizes the splendor of Oakland and the East Bay."

June 24, 1998: The commission selects the suspension bridge, which has an estimated cost of $1.4 billion and a 2004 opening date. But Treasure Island-friendly ramps are left out of the project.

July 1998: Willie Brown now says a northern alignment will be ruinous to Yerba Buena Island -- and the Navy bars Caltrans from visiting the island to collect geological information. This makes it impossible to begin design of the tower or the western end of the eastern span.

November 1998: Residents of San Francisco, Oakland, Emeryville and Berkeley vote that passenger rail service should be "part of the redesign of the Bay Bridge" -- an advisory measure initiated by Willie Brown.

February 1999: The Bay Bridge Design Task Force and its advisory panel reconvene to hear the complaints being made by San Francisco and the Navy.

The approved design "is hopelessly delayed due to a variety of factors," says Annemarie Conroy, Mayor Willie Brown's project manager for Treasure Island. With her is Rear Adm. Ronne Froman, who says the Navy will oppose the approved alignment because "the proposed northern alignment effectively destroys the ability of the city to redevelop the Yerba Buena property to its fullest potential." Neither Conroy nor Froman mentions the potential danger of earthquakes.

March 1999: New Gov. Gray Davis says he supports the approved design.

July 1999: Davis sends a letter to the secretary of the Navy protesting "the Navy's refusal to permit geological testing on Yerba Buena Island," because "every day of delay in completing this seismic safety project courts another disaster."

May 2000: With the approval of White House Chief of Staff John Podesta, the Department of Transportation takes the disputed land on Treasure Island from the U.S. Navy and clears the way for the approved design to proceed.

2002: Construction begins on the new eastern span. But with the estimated cost now at $2.6 billion, and a target opening date of 2007, state legislators demand explanations for the setbacks. A California State Auditor report attributes part of the problem to the Bay Area's choice of a "signature" design. It also says that as a result of actions by the Navy, "the design and environmental process for the eastern span was delayed by nearly two years."

May 2004: The lone bid to build the eastern span's tower is $1.8 billion -- more than twice the $733 million most recently projected. Bridge estimate now tops $5.5 billion. The Schwarzenegger administration rejects the bid.

December 2004: Schwarzenegger proposes making the entire bridge a skyway, saying that changing the design can save $400 million and trim a year off the construction schedule -- even though the proposed scheme has neither a design nor environmental approvals.

June 2005: State Legislature approves $4 bridge toll beginning in 2007 that will allow the tower to remain; as a result, Bay Area commuters will pay 80 percent of the bridge project, rather than the 50 percent originally agreed upon.

March 22, 2006: State to open new bids from construction firms to build eastern span tower.

E-mail John King at jking@sfchronicle.com.

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