In the deadly scenario imagined by Curtis Mitchell, co-owner of Mitchell Engineering, the bridge's true counterweight, a million-and-a-half pound block of iron-ore-infused cement hidden in a chamber underneath the bridge, is too heavy for the steel pivots that support the bridge span. One day, while the bridge is being elevated to make way for a passing boater, Mitchell imagines the steel supports around the pivot might strain, then buckle. The span could crash down to China Basin Canal, crushing watercraft underneath.
"One of the concerns is that something might happen, and they will blame us, and that's not right," says Mitchell, as he gives me a tour of the new bridge, one block southwest of the Giants' ballpark. "That's why I'm willing to go on the record and draw attention to it. Because it's just not right."
Waterborne San Franciscans really needn't begin donning hard hats, however. Mitchell hasn't done any meaningful engineering analysis to back up his assertion that the bridge is poised to collapse. He has made his claim as part of an argument that the city owes him money for cost overruns and delays, because, he alleges, the Department of Public Works gave him badly designed plans.
Mitchell's own staff engineer assigned to the bridge, meanwhile, does not feel comfortable repeating his employer's assertion that it is unsafe because the bridge and its counterweight are too heavy.
"I have my own little reputation to protect," he says, in declining to repeat Mitchell's claim about the bridge weight.
So why does Mitchell make such an alarming, confrontational, and spurious-seeming assertion?
The answer to that question lies at the heart of a civil engineering crisis that threatens to cost San Francisco many billions of dollars in construction and materials costs, as the city struggles to find contractors willing to undertake massive projects such as bridges, electricity infrastructure, and the retrofit of the Hetch Hetchy water delivery system. If something isn't done to change the system, the Hetch Hetchy rebuild price tag could escalate from $4 billion to many billions more.
As extreme as they seem, Mitchell's statements are prosaic in the context of the city's conflict-based system of hiring and overseeing private companies to construct public works. Critics both in and outside city government describe a system where sometimes flawed engineering plans are used as a battleground for financial advantage, as the city and private contractors fight over who should bear the expense of costly mid-project design changes. Rather than rapidly and amicably resolving such problems, the city has gained a nationwide reputation for allowing design problems to repeatedly explode into lawyerly disputes, costing contractors, and the city, millions of dollars in delays and cost overruns.
The system's resulting reputation for generating hostility has gotten so bad that civil engineering firms now routinely decline to bid on city projects, a situation that threatens to delay billions of dollars worth of scheduled work on the Hetch Hetchy water system, electricity generation facilities and other projects, adding many billions in additional city costs.
"If we do not shape up our contracting procedures, there is no telling where this thing could go. Things could go through the roof," said San Francisco Public Utilities Commission President Richard Sklar in an interview. "The number could be infinite."
Last Tuesday Mitchell took me down a narrow stairway into the barn-sized cement chamber below the bridge. It houses an only slightly smaller, iron-ore flecked rectangular mass of concrete that represents the latest in a series of engineering debacles that set the bridge project back more than a year, leading the city and Mitchell to dispute more than $10 million in costs.
Drawbridges are typically constructed by balancing a bridge's span opposite a heavy counterweight astride a pivot, similar to a teeter-totter. In this way, a relatively tiny force is required to raise and lower the platform.
In a classic design such as the original 1917 Fourth Street span, the mammoth weight hangs in the air over traffic, lowering to the ground every time the bridge makes way for passing boats. In the re-constructed bridge, the weight was positioned underground, so as to be safer in the event of an earthquake. But to keep the appearance of the old bridge, sculptors, who do much of their work creating floats for Disneyland, were hired to construct a hollow fiberglass duplicate of the old weight to hang in public view. The underground location of the real weight created new problems, however. Because it hung at a different angle than the old weight, it had to be heavier in order to easily lift the bridge span. But it had to remain the same size, meaning Mitchell had to buy extra heavy cement containing iron ore.
"See how the flecks shine in the light?" asked James Hawkes, the bridge's project manager, as we made our way through the narrow space between the weight and the chamber wall.
The time required to ship the iron ore from Kentucky, then convince a cement plant to handle it, caused weeks of delays. This is the sort of obstacle typical of public works projects, which require applying the math and measurement of engineering to changeable things such as canal banks and bridge spans. Yet it's the kind of issue engineers and city officials acknowledge San Francisco seems ill prepared to accommodate.
Just like other cities, San Francisco is obliged to put construction projects out to bid, then accept the lowest offer put forth by a contractor qualified to do the work. This system is set up to avoid cozy cronyism that might ensue if city officials were allowed to award contracts based on personal preference, rather than price.
This anti-corruption, low-bid system is far from perfect, however. Drawbacks include a propensity by bidders to bid lower than they can really afford, hoping to make up the difference with expensive "change orders," which are required when the original design doesn't accommodate real-world engineering problems encountered in the field. This strategy provokes an equal and opposite reaction among city bureaucrats loath to be gamed by wily construction firms. They adopt a fighting pose, and challenge proposed design changes as a matter of course, letting city lawyers sort out the resulting disputes once the job is done.
"The outcome is that we're not necessarily getting the number of bids we want to. And we're not having the relationship with contractors we might want to have," says Robert Beck, deputy director for engineering of the San Francisco Department of Public Works.
In April, the city attempted to attract contractors to bid on a project to build a gas-turbine power plant to replace ones at Hunters Point and Potrero. But there were no takers. In an effort to explain the lack of interest, Public Works officials interviewed contractors in the aftermath of the power plant bid debacle. And contractors cited the city's contentious system of contract management, of which the Mitchell's dispute with the city over delays building Fourth Street Bridge is a prime example.
The city must soon begin issuing bonds to pay for some $4 billion worth of work on refurbishing the Hetch Hetchy water delivery system. If the city can't attract high-quality bidders, and can't get the projects completed swiftly, skyrocketing materials costs could cause the project's price tag to double, triple, or worse.
Sklar refers to the bidless power plant project as a wakeup call.
"Now is perhaps one of the worst construction environments you could go into. Material prices are skyrocketing across the country. Aluminum has doubled in the past year. Steel and cement are going through the roof. Here we have contractors with lots of other work, material prices high, and a city that puts out onerous contracts. So the city has to come up with new ways of contracting," Sklar says.
In an ideal contracting world, sharp-eyed city managers draw up top-notch engineering plans. Contractors are profit-seeking, but highly competent and fair-minded. When the contractor encounters an unforeseen problem and asks for potentially costly design changes, a steely-eyed genius of an engineer working for the city is at the scene in a flash to hand out a Solomonlike decision about whether the city will pay for the extra work. If not, she suggests an alternate engineering solution, or determines the contractor is stepping out of line. Ideally, that city-employed field engineer would have sufficient authority to make such decisions stick. And she would enjoy a reputation for fairness and toughness, so that contractors would view accepting such on-site engineering decisions as in their best business interests.
Such a system would require screening out abusive contractors who try to make their profits by gaming the city. It so happens city officials are now studying the possibility of such a screening program.
It would require a first-rate design process by the different engineering departments that now serve Department of Public Works, the airport, the Public Utilities Commission, the Municipal Railway, and other departments, so that contractors wouldn't be tempted, as they now are, to quibble over perceived design flaws.
This is one of those intractable city crises, spread over various departments representing disparate special interests, that can't be solved without leadership. Such a solution would require peeling away bureaucracy and putting top-notch people in the field, so that engineering problems could be resolved than foundering for months in lawyer-land.
Anything less than a dramatic reform of our system of public works construction could end up costing our city billions of extra dollars over the next few years, bankrupting other city programs such as health care, transportation, parks, and public safety.
But any real fix would require the kind of daunting bureaucratic reform that involves stepping on toes, breaking up fiefdoms, and abolishing sinecures. It's the type of reform the mayor shied away from undertaking in the area of civil service reform, despite much fanfare last year.
The city's financial future is at stake this time around. Fixing bridges and pipes and power stations without bankrupting the city is hardly the sort of issue one can easily hang campaign slogans from. But if Gavin Newsom doesn't do something, the city's finances, along with the mayor's political reputation, could be headed for a death trap.