On a clear weekday morning, I boarded the 113 bus, which runs from White Center into downtown Seattle, and sat down near the back as the bus merged into Georgetown traffic. The dozen or so occupants near the front were quiet and sleepy-looking. Little did they know what I was about to do. I imagined the scenarios that would make this a killer story. If I jumped and slammed my feet back down into the floor of the bus with punishing force, might the viaduct tremble? Would a hairline fracture creep across one of the highway's support pillars? Would that wake leaders up to the urgent need to just shut this thing down already? Or would the entire edifice instantly tumble down, sending our bus crashing into the waterfront Ferris wheel?

The viaduct was damaged in the 2001 Nisqually earthquake, and we've heard every year since then about the need to tear it down. The state's own video simulation shows that if a 7.0 earthquake occurred today, the top level of the viaduct would break off and fall onto the level below. The bus was on the top level; at least we would not be crushed. Maybe we'd survive, stagger outside, and search frantically for survivors from the lower levels.

With all the heaviness of my five-foot-nine-inch, 150-pound frame, I stood in the aisle and jumped right as we were passing the Bertha excavation pit. Midair, I caught a glimpse of something I wasn't expecting to see: a Honey Bucket porta-potty suspended high above the ground. It was being lowered into the pit by a crane. I landed. We kept rumbling along. Then I sat back down.

Nothing happened that I know of, except I learned where tunnel workers shit.

Using computer models, the mathematician Edward Lorenz coined the term "butterfly effect" in 1972 to describe a phenomenon in chaos theory wherein the flapping of a butterfly's wings can trigger a cascade of tiny changes that lead to larger ones, like tornadoes. I do wonder what Lorenz would say about my jump. I also wonder if my jump set off a chain reaction that led to the crane jostling the porta-potty ever so slightly, making for a messier tunnel pit entrance than was planned—I couldn't really see. We'd already passed it. recommended