LINCOLN, Neb. – Two high-rise dormitories at the University of Nebraska-Lincoln crashed to the ground Friday in a planned implosion that sent chalky smoke plumes billowing through the downtown campus.
The university demolished Cather and Pound halls simultaneously in about 10 seconds. Crews spent several weeks placing dynamite into support columns on select floors and wiring charges to ensure the detonation went as planned. Roughly 500 pounds (225 kilograms) of dynamite was used.
Preparations began in May, when the Controlled Demolition, Inc., the university's contractor, began removing windows, heavy furniture and mechanical parts from the 13-story dorms.
Engineers estimate each building weighed 200 million tons (180 million metric tons). The dorms had housed thousands of university students since 1963, but were outdated. A 2010 study found a batch of safety, code and facade deficiencies with both buildings and concluded that renovating them would cost too much.
Imploding the buildings proved more feasible than destroying them with a wrecking ball or other methods, said Larry Shippen, the university's associate director of housing facilities. University officials also wanted to demolish the building quickly during the holiday break, when few students are on campus.
"Today's demolition is the result of many months of planning and preparation," said Sue Gildersleeve, the university's housing director. "Safety has always been the highest priority, and on a congested college campus like this, it has been an understandable challenge."
Barriers were put in place inside and outside the buildings to keep material from flying out and damaging nearby structures.
Nine square blocks around the dorms were evacuated Friday morning. Roughly 300 spectators watched the implosion from atop a nearby parking garage. A few minutes later, after the smoke cleared, all that remained were two piles of concrete roughly 30 feet (9 meters) tall.
Grant Watson, the university's construction manager, said crews will begin cleaning up the rubble next week, and the last remnants are scheduled to be taken to a landfill early next year. The demolition was expected to cost an estimated $7.3 million.
Watson said university officials walked around the site shortly after the implosion and noticed no damage to other buildings except for one cracked window.
Gildersleeve said university officials haven't yet decided what to do with the site. Once the debris is clear, it will serve as green space at least temporarily.
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