It’s time, I’m afraid. I’ve put it off as long as I can, hoping for some new information. There is something new today–not much, but since the pile of newspaper clippings is threatening to avalanche down and bury my writing desk, I think it’s time for a Bay Bridge update. Brace yourselves.
For those of you who might be bored with the bridge, here’s the tl;dr: As far as we know, the Bay Bridge is perfectly safe for daily use. If there’s a significant earthquake, it might fail.
Ready? As usual, most of the information comes courtesy of Jaxon Van Derbeken’s articles in the SF Chronicle. All praise to Jaxon.
There’s a lot of redundancy in the reports, so I’ll summarize chronologically.
- 2015-05-08 – One of the rods anchoring the Bay Bridge to its foundation has failed under testing. The integrity test was done because the rods were improperly sealed and have been sitting in salt water for years. Engineers feared they might have become corroded. The rod will be tested to determine whether it was corroded. There is also some evidence that there may be cracks in the foundation allowing salt water to attack the steel rebar embedded in the foundation itself.
- 2015-05-09 – An unsigned editorial supports U.S. Rep Mark DeSaulnier’s call for an independent expert review managed by the federal Department of Transportation.
- 2015-05-10 – Caltrans continues to state that the bridge is safe and the anchor rods aren’t actually necessary to support it. Independent engineers are dubious and think an independent review should be done, if only to address why Caltrans spent so much money on “unnecessary” rods.
- 2015-05-10 – Matier and Ross quote Metropolitan Transportation Commission chief Steve Heminger as calling the Bay Bridge “the projext from hell,” and saying “…when it comes to quality control, we are just not getting our money’s worth.”
- 2015-05-12 – The MTC approves spending up to $4 million in toll revenue to test the broken rod.
- 2015-05-15 – Traffic is so slow on the bridge in the morning that the Bay Area regional transit is studying the possibility of changing one of the eastbound lanes out of the city into a westbound transit-only lane during the morning commute. It would require a number of changes, including the installation of a moveable barrier similar to the one that was recently installed on the Golden Gate Bridge; the estimated cost for the entire suite of changes is between $51 million and $177 million. The proposal is far from adoption, but will be studied further.
- 2015-05-17 – The broken rod is six inches shorter than it should be, suggesting that it broke, rather than having been properly anchored. Now that funds have been allocated, it will be removed for testing shortly.
- 2015-05-21 – Visual inspection of the rod by independent engineers suggests it shows corrosion patterns similar to those on the original broken bolts back in 2013. Caltrans refuses to agree or disagree until formal testing is done.
- 2015-05-28 –
The Warriors won the NBA’s Western Conference titleOne of the Bay Bridge’s anchor rods failed while being strength tested. It will have to be tested to determine whether corrosion was the cause of the failure.
- 2015-06-04 – The failed anchor rod broke because it had a bad thread, not because of corrosion, unlike earlier failures. The bad news is that Caltrans’ quality control processes didn’t spot the incorrect threading. The article quotes an independent engineer as saying that many of the rods cannot be replaced if they fail because there isn’t enough space to remove them and place new ones.
- 2015-06-05 – Roughly a quarter of the rods that connect the bridge to its foundation are sitting in corrosive salt water. Three of the rods have failed–i.e. broken–since the bridge opened two years ago.
- 2015-06-10 – Remember a while back when the powers that be decided to make some of the metal from the old bridge available to artists? Matier and Ross report that the cost to strip off toxic lead paint, cut up the metal, and deliver it to the artists will run $2.2 million and be funded from bridge tolls. I’m hoping that somebody has requested a set of bolts from the old bridge to be sculpted into caricatures of the politicians and members of the bridge design committees who insisted on a “signature” design.
- 2015-06-24 – Caltrans admitted that the broken rods show signs of hydrogen embrittlement similar to the original 2013 bolt failures and agreed that the problem could be widespread and put the foundation at risk in an earthquake. Brian Maroney, the chief engineer on the bridge project, told the Metropolitan Transportation Commission that the rods could be replaced, repaired, or modified. Replacement would, of course, be expensive. The committee decided not to allocate funds to clean and protect the rods until a panel of experts reports in.
- 2015-07-10 – The panel agreed to spend $1.1 million to develop a plan to prevent further damage to the rods, despite the fact that a seismic review panel stated that the bridge doesn’t actually need the rods. At least toll-payers will be getting a lot for their money. It’ll cover the design of a dehumidification system, find a grout or other chemical that will keep water away from the rods, conduct further tests on the extent of the embrittlement, and buy “jacking equipment” that can be used in testing and repair. Are they really planning to jack the bridge up off its foundation to replace the rods? If so, I trust they’ll at least close it to traffic while the work is in progress…
- 2015-07-16 – The rubber that covers the expansion joint at the west end of the eastern span of the bridge apparently has an affinity for traffic warning flares. Twice this week a lit flare has rolled against the cover, setting it on fire. Keep in mind that this is still at the level of coincidence–once is chance, twice is coincidence, three times is enemy action (or in this case, a new bridge failure mode)–but it certainly seems perfectly in character for the Bay Bridge. Maybe the California Highway Patrol should start a program to develop LED-based warning lights to replace their flares.
The fun continues. Stay tuned.