Online for twenty years (2002-2022)




Tacoma Narrows Bridge (Galloping Gertie)

(source: James Bashford (creative commons licensing))

Living in the Puget Sound area for a majority of my life, exploring, photographing, and documenting many parts of the Puget Sound for several years has been a fun hobby, but most of the time, this section of Puget Sound was recorded the most.

To find a major suspension bridge being constructed in the 21st century in America is rare. A major suspension bridge hasn't been constructed since 1964 in the United States. While many major suspension bridges have been built in other parts of the world for the past several years, the lessons about the application and their design happened right here as American was getting involved in World War 2.

The first Tacoma Narrows Bridge was constructed in 1939 and went into service on July of 1940. When constructed, it was the third largest suspension bridge in the world. Only the Golden Gate and San Fransisco Bay Bridge were larger.

Unlike the suspension bridges built in San Francisco, this bridge was built on a very low budget using cheap beams and girders to create a two lane bridge that looked like ribbon and moved freely in the wind.

Engineers didn't see a reason to test bridges in a wind tunnel. After the bouncing of the roadbed was reported to the engineer (Leon Moiseiff) he did indicate that the Bronx Whitestone Bridge and the Deer Island Bridge were doing the same thing, it became the responsibility of the state to find out why it was happening and how to prevent it.

University of Washington Engineering Professor Farquarson made a scale model of the bridge to test the affects of wind using a wind tunnel. To solve the bouncing, it was decided to add additional cables below the bridge and secure them using concrete block or cables connected to the towers. While this helped in 50 mph winds, early November was a stormy time of the year and eventually the cables broke (many bridges today use additional cable supports above the roadbed rather than below).

It was during this time that Professor Farquarson would present his findings to the State of Washington. His suggestions were to either drill holes in the side beams or using fairings on the outer sides of the bridge to deflect the wind. The state was interested in the fairlings (they didn't want to drill holes in the bridge) and could have had the work completed within 40 days but it was too late.

The center span of the bridge fell on November 7th 1940 at wind speeds that had gusts from 38-42 mph after the bridge twisted from side to side for about 30 minutes.

The video produced by Barney Elliot shows the roadbed movement while a vehicle (left on the roadway) was left behind by Tacoma News Tribune reporter Leonard Coatsworth.  Farquarson and others tried to get the dog, Tubby from the vehicle but the dog didn't want to get out of the vehicle biting those that tried.