Caltrans: New Bay Bridge is safe, well-tested 

A recent Sacramento Bee story omitted important facts and context in a way that misleads the public about the safety of the new Bay Bridge. Unfortunately, a San Francisco Examiner editorial (“State must ensure safety of new span,” June 5) repeated these untrue claims, so Caltrans thanks The San Francisco Examiner for the opportunity to respond — especially since the Bee refused to print a rebuttal.

The truth is that the new Bay Bridge is one of the safest bridges in the world. It was designed to exceed normal safety requirements. Every concrete pile in the new bridge’s tower foundation passed at least three rigorous, mandatory safety tests. Every aspect of the bridge has been tested, checked and re-checked. These tests were reviewed by internationally renowned experts who confirmed the bridge’s integrity and seismic safety.

The Bee’s story skewed the facts by focusing on one type of non-required test on these piles — a “sonic test.” This optional test was performed before the concrete had hardened and therefore inaccurate results are not surprising. However, the Bee’s mischaracterization of the testing raised false alarms about the bridge in media outlets statewide.

The reality is that all 13 piles on the Bay Bridge tower foundation were carefully tested using three separate methods: rigorous radiological tests, concrete cylinder break tests of concrete from the actual piles and concrete slump tests. Each of these mandatory tests confirmed the structural integrity of the bridge.

All foundation work was performed under close observation by expert engineers, and the test results were reviewed by the Federal Highway Administration and an independent Seismic Safety Peer Review Panel. Both groups drew the same conclusion: The bridge far exceeds safety standards.

The safety of a bridge is never determined by a single test. Instead, expert engineers perform field inspections and review large quantities of data from multiple tests to confirm that a structure is sound. By focusing on one optional test and ignoring several state-mandated tests, the Bee created a false impression.

For example, the Bee article describes an alleged “19-foot anomaly” found by an optional test. This test identified an area in which the concrete had not yet hardened, but the Bee ignores subsequent state-mandated test results and inspection records that found the concrete had hardened and the pile is structurally sound. The independent peer review panel reached this same conclusion.

The Bee quotes part of an engineering report to insinuate that Caltrans erred in not retesting. The very same report recommended a “gamma-gamma” test as an acceptable alternative. The Bee omitted this recommendation from its story and failed to report that Caltrans actually did perform this mandatory gamma-gamma test, which confirmed the safety of the pile.

In light of the grievous flaws in the Bee article, Caltrans has taken the unusual step of asking for a full retraction of the story. The safety of millions of Californians depends on the work Caltrans does on structures such as the Bay Bridge, and we take our job very seriously.

Once finished, the new span of the Bay Bridge will stand as a modern engineering marvel of which all Californians can be proud. The Bee story wrongly created public apprehension about the safety of the bridge, and the paper’s editors should do what’s right and set the record straight.

Malcolm Dougherty is the director of Caltrans.

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Malcolm Dougherty

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