73 years later: How ‘Galloping Gertie’ changed how bridges were designed

TACOMA – More than 73 years ago this week, another strong storm in the Northwest made headlines across the country.

Powerful winds brought down the old Tacoma Narrows Bridge 73 years ago Thursday. Known as ‘Galloping Gertie,’ 40 mile-per-hour winds rocked the span, making it twist like a ribbon until it snapped and crashed in the Narrows Strait.

A Tacoma News Tribune editor was trying to drive over the bridge, but was forced to abandon his car. Thankfully, no lives were lost.

The disaster changed the way engineers designed bridges. Authorities believe the cause of the collapse was instability. According to the Department of Transportation, the $6 million suspension bridge was considered state-of-the-art when it was built. Before the bridge collapsed, University of Washington professor, F. Bert Farquharson was asked to look at the engineering of the bridge.

Because Gertie would normally sway in the wind, he recommended cutting holes in the solid girders to let wind pass through, or cover the girders with curved steel to deflect the girders.