SEATTLE -- After 15 years of discussions, meetings, budgets and preparations, crews will begin staging for construction of the new 520 bridge on Lake Washington this week.

WSDOT unveiled the latest design plans for the $4.65 billion bridge Monday. Stating this week, huge barges will get into position for construction, which could begin as early as summer.

As weeks go on, dozens of huge pontoons, equipment and other pieces of the bridge will be towed into the workzone before construction kicks off.

The new bridge will be built along the north side of the existing 520 bridge.

View step-by-step construction plans for the new 520 bridge

The new 520 bridge will be built with six lanes with dedicated HOVlanes in each direction, pedestrian paths, plus viewpoints. WSDOT said when completed, the new 520 bridge will be the longest floating bridge in the world. It is slated to open to traffic sometime in 2014.

Two open houses will be held this week in Medina and Seattle for the public to learn more about 520 construction:

  • Medina: 4:30 to 7:30 p.m. Tuesday, March 27, at Three Points Elementary School, 7800 NE 28th St., Medina
  • Seattle: 4:30 to 7:30 p.m. Wednesday, March 28, at the Museum of History & Industry, 2700 24th Ave. E., Seattle

To learn more about the entire 520 project, visit

Read or Share this story: