The roof of The Dome sports complex in Anchorage, Alaska, collapsed January 21, 2017, over a several-hour period. The 180,000-sq.-ft. complex, built in 2006, was designed, according to Mike Martin, the chairman of the board of the facility, to support two inches of water column pressure and “was about 1.9 last time I looked…maybe 30 minutes before the top came down,” Martin said. The facility had been evacuated prior to the collapse, and no one was injured.
The structure claimed to be the largest such air-supported structure in the world. Pressurized air inflates the fabric envelope, which is secured by pipe and cable ground anchors. It was used by various local sports teams and housed a USA track, a full-size soccer field, full-sized football field, weight equipment, batting cages, and more.