Construction gets rolling on replacement SR 520 floating bridge

From guest blogger Jeff Switzer

Sideways rain in Grays Harbor last weekend couldn’t stop more than 200 people from cheering the start of construction on the SR 520 pontoon project in Aberdeen. Gusts from the coast that roared up Saturday only underscored the need for project everyone was celebrating: The aging SR 520 floating bridge on Lake Washington is vulnerable to windstorms and we are going to replace it.

The 33 pontoons – giant floating concrete boxes – to be built in Aberdeen starting this year will form the backbone of a replacement bridge.

Local carpenters and trades workers turned out to celebrate, saying they’re ready to start earning paychecks on the project. We’ve been working hard to get started on construction, and Grays Harbor is eager for the work. The $367 million project will ramp up to 300 direct construction jobs later this year.

Work starts this week on a casting basin – a big bathtub of a work zone on Grays Harbor. The basin will be connected to the water so new pontoons – many as long as a football field – can be built in the basin, floated out and towed to Seattle. They’ll each be three stories tall and narrow enough to fit through the Ballard Locks when complete. Some of the 33 new pontoons will weigh 11,000 tons each – as much as 23 Boeing 747s.

Take a look at our step-by-step guide to building a floating bridge to see what we have planned starting in 2012.

The same windstorm that hit the coast this weekend also sent high winds hammering the SR 520 floating bridge, giving a timely reminder why building a new bridge is so important. Since 1993, we’ve repaired about 30,000 feet of cracks in the pontoons to keep the bridge afloat and safe for traffic – but it’s time to build a stronger replacement bridge. It’s scheduled to open to traffic by the end of 2014.

Check out the Flickr photos, our YouTube video or our project page for more about the project.