Sound Transit preps for 'floating bridge' post-tensioning

Sound Transit on July 20 will begin post-tensioning work on its floating light-rail bridge across Lake Washington in Seattle.

Crews will tighten high-strength steel strands to strengthen the bridge, which runs along Interstate 90 as part of the $3.7 billion East Link light-rail project.

The work will enable the bridge to withstand stronger winds and higher waves, and strengthen it to carry light-rail tracks and vehicles, Sound Transit officials said in a press release.

The post-tensioning work is slated to be completed July 29.

Since June 2017, crews have placed 10 steel reaction frames into each of the two pontoons on either end of the bridge's flat portion.

When it opens in 2023, the East Link line will extend light rail 14 miles from downtown Seattle to downtown Bellevue, Washington, and the Overlake area of Redmond, Washington.

A year after that project is completed, Sound Transit plans to open another 3.4-mile extension further east to new stations in southeast Redmond and downtown Redmond