First pontoon placed for SR 520 bridge is from Aberdeen
Pontoon A is the 2nd to be placed on Lake Washington, and built in April 2013. It floated out of Grays Harbor in June of last year.
The newest pontoon to be permanently placed on Lake Washington for the SR 520 Bridge, will be a pontoon built in Aberdeen in April of last year.
The 240-foot-long, 10,000-ton Pontoon A, was placed on the lake with large roadway-support columns mounted atop its deck. Pontoon A on the west and Pontoon W, now anchored near the lake’s eastern shoreline, will bookend the floating bridge’s 21 longitudinal pontoons.
“This pontoon placement essentially represents the start of bridge assembly,” said Julie Meredith, of the SR 520 Program Director. “In coming months, the public will start to see a new floating bridge take shape as we align and connect other pontoons in between A and W.”
On Saturday, crews towed Pontoon A to its permanent location about 50 feet north of the existing floating bridge. This week, the pontoon will be secured in place with steel cables attached to anchors secured to the lakebed.
Fifty-two of the new bridge’s 77 pontoons have been constructed so far, with 34 now on Lake Washington. 4 pontoons from cycle 3 left Grays Harbor this month and 6 more from cycle 4 left the casting basin last week. This means that two-thirds of the 33 pontoons constructed locally are now complete.
The new bridge is scheduled to open to traffic in spring 2016.