At 8:32 a.m. on March 26, 2000, Seattle's Kingdome is imploded. The Kingdome stadium's 660-foot concrete dome is the world's largest. Thousands of spectators crowd Seattle's streets, hills, sidewalks, and waterfront to watch the dome's destruction. Onlookers view the implosion outside a "restricted zone" that extends several blocks around the stadium. The blast sets off a small earthquake measuring 2.3 on the Richter Scale. The Kingdome, originally called the King County Multipurpose Domed Stadium, opened on March 27, 1976.
The implosion took place in two phases. The Kingdome's ribs were grouped into six evenly spaced sections. Three sections collapsed in Phase I, and the remaining three fell many seconds later. Two wires circling the Dome set off six electrical charges, lowering the six sections in careful sequence. The implosion took 16.8 seconds.
The first set of explosions cracked the structural system: the ribs, the columns, and the tension ring circling the stadium. The building's rebar, reinforcing steel rods running through the Kingdome's many concrete elements, fell inward as concrete elements explosively fractured. The aptly named Controlled Demolition Inc. orchestrated the implosion, which was considered "beautiful" by demolition experts and which awed bystanders. The implosion proceeded as planned, three seconds more quickly than estimated, with minimal impact on the surrounding neighborhoods.
Many onlookers gathered pieces of concrete rubble as souvenirs of the Kingdome and its climactic end.
Though impressive, the Kingdome's destruction disturbed many residents. The Kingdome was part of a 1966 capital improvements plan called "Forward Thrust," and was budgeted for $40 million. Siting debates slowed the stadium's construction, pushing costs higher as inflation and interest rates rose in the early 1970s. When the building was imploded, King County, Washington, still owed $206 million on it.
