Tag Archives: San Francisco – Oakland Bay Bridge

Bay Bridge Review

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I drove across the new Bay Bridge yesterday. In both directions, even.

I survived (well, duh: how would I be writing this if I hadn’t?). So did the bridge. Amazing.

It’s not without its quirks. That’s probably a good thing in the long run. Quirks add uniqueness, and now that the Bay Area has proven that a self-anchored suspension span can be built in this size, others will undoubtedly be built. If the Bay Bridge is going to remain unique long enough to justify the price tag, it’s going to need some quirks. “We just built an SAS bridge 50% longer than yours!” “Oh yeah? Well, does it have re-purposed disco lights for traffic metering?” Other quirks: the traffic chaos at the toll plaza continues to make safely navigating through the Maze look easy. The 50 mph speed limit feels like it’s much slower than it should be, given the long, straight roadbed.

Quirks aside, the bridge largely meets the aesthetic goals that were set by the assorted politicians who meddled in the design. It certainly draws the eye, and once the old span is dismantled (a three-year process!), it will dominate the landscape from most viewpoints. It fails a little when driving east: coming out of the Yerba Buena Island tunnel, you don’t really get quite the same visual impact from the suspension cables as you do approaching them from the other direction. They’re just suddenly there, rather than growing to surround you.

The lighting system is a huge design victory. The light poles are visually distinctive, and feature low-energy LED bulbs that are carefully-aimed to avoid ever shining into drivers’ eyes. According to plan, the bulbs should only need replacing every 10 to 15 years, which is great in terms of cost and power usage. I wonder, though, how easy it will be to replace them without ruining the precise orientation that keeps the light even and motorists un-blinded. That’s a quibble, and I’m sure we’ll find out how it works out long before 2023, as some of the bulbs will inevitably not reach the 10 year design goal.

That speed limit is going to be a continuing issue. Not at rush hour, perhaps, but at other times, drivers are going to regularly exceed it by a significant margin. I saw quite a few cars doing an estimated 65 or 70 yesterday, and I’d be willing to bet that will be “business as usual”. Maybe that’s a design feature. Since the new span has a shoulder, it should be possible for the CHP to pull speeders over and issue tickets. Could be a nice little supplement for somebody’s budget — as soon as the various powers-that-be settle the question of how the funds will be allocated. Or maybe they’ll install speed bumps and turn the bridge into the world’s longest roller coaster ride.

Bottom line: Until its seismic safety is demonstrated by something more than the 2.9 magnitude quakes it’s weathered so far, the public will continue to be dubious about the bolts, the saddle, and the shim. But the new span is beautiful and much more pleasant to drive across than the old one. Here’s hoping the engineers are right and that the new bridge lasts — and not just because it’s got a huge price tag to justify!

YABBBBP

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OK, now this is the way it’s supposed to work. Well, sort of, anyway.

As we’ve discussed before, the way QA is supposed to work, somebody runs a test. If the test fails, that gets reported up the chain so that responsible parties can decide when and how to fix the problem. The fix gets tested, (hopefully) approved, and everyone is happy.

Amazingly enough, that almost happened with some aspects of the Bay Bridge construction!

Remember back in May, we heard that expansion joints on the new east span’s bike path had been incorrectly welded, so that they didn’t actually expand? At that time, I said “Seriously, though, the bike path was installed in 2008, yet the improper welds weren’t discovered until an inspection was done in 2012. Where the heck was the QA? Didn’t anyone check the installation at the time it was done?” It turns out that an inspection was done in 2008. The improper welds weren’t discovered at that time because other problems concealed them.

Jaxon reported in today’s Chron that one Greg Roth (hey, we’ve got an actual name!) inspected the bike path in 2008 and reported problems with the fence along the side of the path. Specifically, emergency access gates didn’t open, grills and grates didn’t fit, and flawed parts were used to anchor the path to the bridge.

After reviewing the problems, “Caltrans” (darn, we’re back to that collective responsibility thing again) determined that the problems were the result of a design flaw. The flawed design was corrected and fixes were installed in 2011. The process was followed, the problem was resolved, and everyone was happy, right? Unfortunately not.

In the course of installing the fixes, crews discovered that metal pieces intended to keep the fence vertical were too thin. These “shims” had a tendency to slide out of place, causing the fence to sag. So the crews replaced the shims, in the course of which they discovered that the bolts holding down the railing had been welded too tightly and had broken. Right: contrary to the earlier report, the expansion joint problem was not found in a planned inspection, but by repair crews working on a related problem.

Still, the process was followed. This certainly isn’t the first time that fixing one problem has revealed additional problems, and it won’t be the last. The problems are fixed (or getting there: there are still hundreds of bolts yet to be inspected). I’m trying to regard it as a good sign.

But, I do worry when I see Caltrans spokesman Will Shuck saying that Caltrans will be more careful in the future. Jaxon quotes him as saying that the remaining portion of the bike path “‘will be constructed in accordance with design enhancements’ that Caltrans has made.” That’s very reassuring, Will. Who reviewed and signed off on the enhancements? Who is going to inspect the work?