The Bay Bridge that Could Have Been (and Where We Are Now)

Butterfly Bridge
The so-called butterfly bridge was never built.

The summer issue of CA-Modern carries the fascinating saga of the Frank Lloyd Wright-designed "butterfly bridge," a proposal for a southern Bay crossing that was never built, but was considered as an option for the Bay Bridge's new eastern span. The design, created by Wright and championed by engineer-collaborator Jaroslav J. Polivka, would have created two flared, parallel roadways with a park between them, a radical departure from the suspension design that finally won out.

As we neared publication of the issue, the details of the bridge's opening seemed to be ever in flux. To avoid publishing information that would be out of date by press time, we refrained from providing an opening date for the long-delayed eastern span. Nor did we include any specific updates on its construction.

Our abundance of caution proved well advised, as the Bay Area Toll Authority announced on Monday the span’s opening would be delayed to December 10. The reason: Repairs to the areas where 32 rods were found cracked in March are expected to take at least three months longer.

Frank Lloyd Wright
Wright envisioned a flared parallel roadway.

Those rods will be replaced before the bridge opens, the San Francisco Chronicle reports. In addition, “more than 700 other rods - about a third of the 2,306 used on the span - will also need to be replaced, and hundreds more will have their tension adjusted to prevent them from cracking. However, that work can be safely performed with traffic running across the $6.4 billion bridge.”

And the Dec. 10 date isn’t even a guarantee. “What we are saying is the contractor's schedule says Dec. 10. It will be up to the (oversight committee) to determine when it should open,” said Randy Rentschler, a spokesman for the toll authority. Now that the opening has been pushed back, plans for a $5 million opening celebration have also been put in jeopardy. A possible quick fix throws the opening date into question even further.

There’s no telling whether things would have been different if Wright’s span had been chosen. And really, it would be useless to speculate here. But it’s impossible not to wonder. From what we learned of Polivka in Dave Weinstein’s excellent profile of the aborted project, one imagines the spirited engineer might have used the delay to make one last Hail Mary bid to get his and Wright’s design built after all.

Photos courtesy San Francisco History Center (S.F. Public Library), Frank Lloyd Wright Foundation Archives (Museum of Modern Art - Avery Architectural & Fine Arts Library, Columbia University), Frank Lloyd Wright Foundation (Scottsdale, AZ), Pacific Road Builder and Engineering Review.