Crews last week began the tricky demolition of the old air traffic control tower at San Francisco International Airport (SFO). The tower, which was decommissioned in October 2016 after the opening of a new 221-ft tower, was built in 1983 and will be removed progressively with the aid of a crane, along with scaffolding on the upper floors of the building.

The $55 million design-build project will also remove the base structure below the former tower, which dates back to 1954 and does not meet current seismic requirements. In place of the old tower, SFO will build a new facility that will include flexible office space, a café, and a public observation area that will take advantage of the views of four runways in sight.

 Construction teams plan to have the top “cab” section of the former tower removed by the end of March. The project scope also includes an additional aircraft boarding gate in Terminal 2, anticipated to be ready for use by the end of March. All phases of the project are expected to be completed by the end of January 2019.

Turner Construction is leading the construction work, while Woods Baggot/AE3 Joint Venture is the designer. Oakland, CA-based Silverado is the subcontractor for the demolition.

One of the most interesting challenges the project team is facing on the job is working around busy Terminal 2, which will remain fully operational during demolition and the rebuilding process, says Doug Yakel, public information officer for SFO.

Yakel says when the demo is complete, crews will save the tower's original 1950s rotating beacon light so it can be donated to an aviation museum in the San Francisco Bay Area.

Last October, the airport officially opened its new Air Traffic Control Tower. The 221-ft-tall tower is said to be the tallest structure in the United States to employ a cutting-edge vertical post-tensioned system, enabling it to remain upright and fully operational after a major earthquake. It was designed by HNTB; San Francisco-based Walter P Moore served as structural engineer; and Rutherford + Chekene proposed the vertical post-tensioned system.

The LEED Gold-rated tower was recognized as the top engineering project in California in 2015 and was honored with the “Golden State Award” by the American Council of Engineering Companies (ACEC) for its "innovative and collaborative approach" to design and construction.