77 years ago Tuesday, Tacoma's 'Galloping Gertie' bridge spectacularly collapsed
TACOMA, Wash. -- Tuesday marked a dubious anniversary in the history of local civil engineering feats -- 77 years ago, the Tacoma Narrows Bridge famously collapsed during strong winds, but not before putting on a ultimate shimmy that made it true to its nickname of "Galloping Gertie."
The bridge had just opened to the public four months earlier and used to oscillate even as it was being built, according to HistoryLink.org. The site says the bridge was build weaker than its original design in a bid to save money -- an ill-fated decision, as it turned out.
The bridge used to sway a bit during windy days in the months leading up to Nov. 7, but on that morning, strong sustained winds over 40 mph hit the bridge. WSDOT historians say the last cars went across the bridge just before 10 a.m. when the bridge was closed due to the radical twisting motion on the road.
Just after 10 a.m. the bridge was twisting so much that engineers estimated the road would tilt back and forth up 28 feet every five seconds at a 45 degree angle. Only the press and a bridge engineer were allowed at the bridge. At 10:15 a.m., the bridge was cleared. A piece of the bridge fell into the Narrows around 10:30 a.m., and at 11:02 a.m. the bridge gave way.
"By 11:10 a.m. it was over," the WSDOT wrote. "The cold waters churned, eddied, and swirled. The heart of Galloping Gertie sank beneath whitecaps, coming to rest on the bottom of Puget Sound."
No people were hurt, but a dog who was left abandoned in a car in the midspan of the bridge as it began to sway perished.
The new Tacoma Narrows Bridge reopened in October of 1950 and was joined by a second span built just to its south in 2007, making each bridge carry one way traffic.