Tacoma Narrows Bridge, "Galloping Gertie," 1940
Tacoma Narrows Bridge, "Galloping Gertie," 1940
This bridge was the first Tacoma Narrows Bridge even though talk of building a bridge at this location between Tacoma and the Kitsap Peninsula dated back to 1889 and a Northern Pacific Railway desire for a trestle. Before the bridge was built there was a ferry across this stretch of water. Financing the bridge also meant buying out the private ferry contract.
Eventually the Washington State Toll Bridge Authority (WTBA) was formed by the State legislature and $5,000 was appropriated for a study to see if a bridge could be built. The suggested tolls would not be enough to cover the construction costs but both the U.S. Navy and the U.S. Army gave the project strong support so the WTBA requested $11 million from the Federal Public Works Administration (PWA). Several consulting engineers were involved in the design and some changes were made partly to save money. Because the planners did not expect heavy traffic it was designed as a narrow two-lane bridge. Design modifications resulted in the use of shallow narrow girders that proved to be insufficient to withstand the winds and it fell to aeroelastic flutter. The failure of this bridge has had a lasting effect on science and engineering. Increased research into aerodynamics-aeroelastics and has influenced the designs of all the long-span bridges built since 1940.
Construction started in September 1938 with completion in July 1940. At the time it was the third-longest suspension bridge after the Golden Gate Bridge and the George Washington Bridge. It was nicknamed Galloping Gertie because right from the time the deck was finished it began to move vertically in windy conditions. Measures to stabilize the bridge were not successful and the main span collapsed in a 40-mile-per-hour windstorm 7 November 1940.
Amazingly only one life was lost and that was a little dog, Tubby, who belonged to Leonard Coatsworth, a Tacoma News Tribune editor, the last person to drive on the bridge. There is a film record of the event made by Barney Elliott who owned a local camera shop. In 1998 the Library of Congress selected the film for preservation due to its historical and cultural significance.
Due to shortages in materials and labor resulting from World War II a replacement bridge was not built until 1950. It was longer and had more lanes than the original bridge. That bridge still stands and today is used to carry westbound traffic. To accommodate increased traffic needs a parallel eastbound bridge was built and opened in 2007.
My Mom and Dad were living in Seattle and Dad was working on the peninsula at the time. He had crossed the bridge several times on his way to and from work between when it opened in July and the day it collapsed. The day the bridge fell he had just driven across and years later when I was a child I remember him telling of watching the bridge fall. He saw Coatsworth crawling and then running to get off and he could also see the little dog that was too frightened to run across the swaying bridge and did not make it to safety. It was a delight to find these cards and be able to put pictures with a story I remembered from my childhood.
For additional information including the personal account of Leonard Coastworth’s escape from the bridge, see:
https://en.wikipedia.org/wiki/Tacoma_Narrows_Bridge_(1940)
Before and after photographs of the bridge collapse can been here:
https://www.flickr.com/photos/wsdot/sets/72157665864730102
No comments:
Post a Comment