You gotta admit that when it comes to closing down infrastructure, nobody does it like Seattle.

Last July, residents of the city’s South Park neighborhood threw a going-away party for a nearby 80-year-old bridge across the Duwamish River that had become too expensive to maintain. (A replacement is currently under construction.)

This past weekend, the Washington State Department of Transportation (WSDOT) opened the Alaskan Way Viaduct to pedestrians, roller derby maidens, and motorcycle-riding acrobats to mark the beginning of the end of the double-decked structure’s service to Seattle motorists.

The festivities coincided with the start of a nine-day closure of the Viaduct, during which the southern mile is being demolished to facilitate the final connection to two new parallel structures that also promise improve access to the South Downtown (SoDo) area.

Though the remaining one-mile central waterfront portion of original Viaduct will reopen to vehicular traffic in time for Halloween, its days are numbered as the last legal and funding hurdles toward replacing it with a $1.96 billion, deep-bore tunnel appear to have been cleared. Excavation for the tunneling work is scheduled to begin early next year, according to WSDOT.

Seemingly loathed as an eyesore almost from the moment it was completed in 1953, the Viaduct is nevertheless an essential component of Seattle’s traffic network, offering the sole north-south alternative through route to perpetually jammed I-5. The 2001 Nisqually Earthquake intensified what had been a long-simmering debate about what to do with the structure, and whatif anythingshould take its place.

So with the Viaduct’s fate sealed and the wrecking ball ready to roll, why not have a party?

On an appropriately foggy and misty Northwest Saturday morning, more than 3,200 pedestrians showed up to stroll the quieted traffic lanes, watch machines gnaw the first chunks of reinforced concrete from the weathered structure, and grab a piece or two of concrete for posterity. (The rain also provided a convenient excuse for anyone feeling a modicum of sentimentality about the Viaduct’s impending demise.)

Also on hand were members of the Rat City Rollergirls, an all-female flat-track roller derby team, and the motorcycle stunt team Seattle Cossacks. Both groups were selected from nearly 600 entries in  a WSDOT-sponsored contest for a chance to have the Viaduct to themselves for 30 minutes each.  

The Rollergirls spent their allotted half-hour speed skating with more elbow room than they’ll ever have in competition, while the Cossacks used the empty roadway as a stage to perform stunts atop their vintage Harley-Davidson motorcycles.

The good humor also provided a much-needed measure of levity to what many feared would be “Viadoom,” a week of tangled traffic, with the Viaduct’s more than 90,000 daily vehicles shunted onto I-5 and local roads (which aren’t in the greatest shape to begin with, according to a just-issued Seattle Department of Transportation report). Thanks to an extensive awareness campaign, police traffic management, and commuters holing up to telecommute for a week (or at least long enough to see how bad things get), the first workday of Viadoom appears to have passed without major incident.

WSDOT hasn’t said what’s in store when the remainder of the Viaduct comes down sometime between now and the tunnel’s projected 2015 completion date. Being in the middle of a major work zone by then, the structure may not be the safest place for casual pedestrians, not to mention skaters and acrobats.

But you can bet that somewhere nearby, there’ll be a party—a final toast to a structure that many couldn’t live with, but many more couldn’t live without.

UPDATE 1145 ET 10/25: That promising start to Viadoom's first day didn't last very long.

UPDATE 0900 ET 10/28: Remember the old saying about things have to get worse before they get better? That's pretty much how Viadoom-related traffic issues have played out.