By Emily Turner

SAN FRANCISCO (KPIX) — It started before noon and became a day-long nightmare for drivers. On Wednesday, Dec. 5, gridlock caused by a jack-knifed semi tractor-trailer on the Bay Bridge lasted well into the evening commute.

If one accident can shut down the city’s traffic flow for hours, what happens in a real emergency?

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KPIX talked to Dr Irwin Redlener of the Center for Disaster Preparedness. He said it should be a wake-up call. “A lot of hard-nosed analysis and open frank discussions with a lot of transparency about what actually happened will need to transpire now,” Redlener said.

But that isn’t happening — at least not yet.

Neither the San Francisco police department nor the California Highway Patrol responded when KPIX asked if they are doing a debrief on Wednesday’s accident.

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A spokesperson at the San Francisco Municipal Transportation Agency said they will be bringing it up for discussion at their regional meeting in February. At City Hall, not a single official was available to talk on camera.

At the Department of Emergency Management, public information officer Francis Zamora said, “We are awake.” In fact, he said, “This is something that we plan for and look at everyday.”

But the department won’t be doing a deep debrief on how or why something as simple as an accident before lunch can shut down a city through evening rush hour. It will, however be running a drill that emulates a similar situation in case of emergency.

It will be testing what’s called a “priority route exercise” next year to practice how to clear debris or cars that block one of the city’s priority exit routes.

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“In the event that we have a closure on a major thoroughfare, we have a plan that we’ve exercised to figure out how do we quickly clear the roadway so first responder assets can come in and then we can respond effectively,” Zamora said.