Ever since the Bay Area's Loma Prieta earthquake in 1989, I have had problems with overpasses. It hits me when I'm in my car, stopped at a light underneath one. The seconds feel like minutes. My heart starts beating faster. My hands get clammy. I stare at the light, willing it to change. In my anxious state, I imagine the massive concrete structure—covered with cars—falling down onto my car, flattening me in an instant. I try to think of a scenario in which I might survive: Could I gun it and narrowly escape the rubble? Could I somehow crouch down into a tiny slot of space and be pried out later? I know in reality neither of those situations would be likely. My death would be most likely. Or, at least, that's what I've told myself since I survived a massive earthquake.

I remember the day clearly. I was sitting at my family's kitchen table, doing my homework after school. My mother had just come home from the grocery store. That's when the shaking began—it was violent, angry, loud. It sounded like the whole world was being ripped apart, like life was ending.

We dove underneath the table. I screamed for it to stop. Eventually, it listened. When the shaking subsided, the chandelier kept swinging. We turned on the TV to see a section of the upper Bay Bridge had collapsed. We watched a car falling into a crack over and over. But the most terrifying devastation happened on another, much closer freeway, in West Oakland: A 1.25-mile piece of the Cypress Street Viaduct (aka the Cypress freeway) collapsed, killing 42 people. The images of the crumbled concrete looked unreal. The survivors included a 7-year-old boy trapped underneath his dead mother. Rescuers had to cut through his mother's body to get to him, and even then they had to amputate part of his leg to get him out of the wreckage.

That was more than 25 years ago. But that day continues to haunt me. I thought when I moved out of California, I might be escaping this feeling of impending doom, but sure enough, it came rushing back to me as I was driving over the Alaskan Way Viaduct on a recent morning. It probably didn't help that I had just watched WSDOT's 2009 simulation video of what might happen to the antiquated structure in the event of a 7.0 magnitude earthquake. The image of the collapsed highway and surrounding devastation looked eerily familiar.

I drove over it on a Friday morning, when the city was shrouded in a thick fog. A sign at the entrance of Highway 99 promises—somewhat cruelly—that the tunnel project will replace the viaduct and "improve safety and mobility." That's not reassuring when it's unclear when (or if) the tunnel project will ever come to fruition. As I made my way north on Highway 99 among a stream of cars, I thought about WSDOT's doomsday video, about Governor Chris Gregoire's insistence back in 2008 that the decrepit viaduct come down by 2012, and about the fact that the viaduct is sinking.

I also thought of the various assurances that have been made by public officials that the Alaskan Way Viaduct structure is "safe." Before it fell down, public officials in California believed that the Cypress freeway was safe, too, according to Bob Bea, a professor emeritus of civil and environmental engineering at UC Berkeley, a cofounder of the Center for Catastrophic Risk Management, and a nationally recognized expert on forensic engineering. Bea says significant advancements in the field of engineering have been made since the 1989 Loma Prieta earthquake, and that these technological developments indicate that "earthquakes happen more frequently and with greater intensities, that their effects on soft soils are very significant and can result in intensifying the earthquake motions, and that structures have to be designed, constructed, and maintained 'properly' if they are to be able to 'safely' withstand earthquakes," he wrote in an e-mail.

The Alaskan Way and Cypress Street Viaducts share(d) commonalities: Both are/were old structures, have/had been weakened by time, and are/were considered technologically obsolete, according to Bea. "Both have/had important local soft soil conditions that can amplify earthquake and time effects," he wrote. "Both are/were very important 'life line' transportation structures whose 'safety' requirements are greater than those of other 'less risky' public infrastructure systems."

But here's the difference: what officials have decided to do about them. In California, the Cypress freeway was torn down and replaced with a surface boulevard (the freeway to the Bay Bridge was rerouted). The same decision was made about the Embarcadero Freeway in San Francisco. Here, the idea of tearing down the viaduct and replacing it with surface improvements never gained enough traction.

So just how risky is using the Alaskan Way Viaduct now? While Bea says he doesn't have significant knowledge of the safety of the highway, he believes that "time has demonstrated that the bridge is 'safe' for 'normal daily conditions.' But, time has not demonstrated that the bridge is 'safe' for 'unusual conditions'... like an intense earthquake... or a terrorist attack... or the long list of hazards that can 'stress' the bridge above its normal daily conditons."

In other words, it's "safe"—until it isn't.

Of course, just like the Bay Area, the Pacific Northwest has its own impending "Big One" on the horizon. I just hope the Alaskan Way Viaduct isn't around when it hits. recommended