Tuesday, April 25, 2017

Happy 1st birthday to the world’s longest floating bridge

By Ashley Selvey
Happy birthday to the new SR 520 floating bridge!

In the predawn hours of April 25, 2016, a few early-bird commuters made history when the new SR 520 floating bridge greeted their vehicles and opened to traffic for the first time.

One year later, the new span – certified by Guinness World Records as the longest floating bridge on earth – is carrying about 77,000 cars, trucks and buses per day across Lake Washington. That's about 30 million trips over the past 12 months!

The new, 1.5-mile-long bridge can boast other superlatives as well. On a clear day (yes, we have those now and again), the bridge affords breathtaking views of Mount Rainier to the southeast or the Olympics to the west. And with its Next Generation Concrete Surface, the bridge is also one of the quietest highways to travel on.
Sunset over Seattle, looking west from the SR 520 floating bridge.

A bridge comes of age
Well over a decade of public discussion and planning about SR 520's future, followed by five years of construction by more than 1,000 workers, preceded the new bridge's historic opening. The result was a structure that will provide the Central Puget Sound region safer, more reliable travel for the next 75 years or more.
The new bridge is bigger and stronger than its structurally vulnerable, four-lane predecessor. With more than twice as many pontoons and heavier anchors, it is designed to withstand much stronger winds and waves than its 1960s-era ancestor. The new bridge also has HOV lanes, which improves transit options, whether it's for daily trips across the lake to work or a weekend jaunt to events on either side of the lake.
At the grand opening of the SR 520 floating bridge in April 2016, visitors experience the bicycle/pedestrian path for the first time.

Another first is that travel across Lake Washington will be possible later this year for pedestrians and bicyclists thanks to a new 14-foot-wide bicycle and pedestrian path.

What's next
In coming years, travel between the floating bridge and I-5 will experience a similar transformation.

This summer the West Approach Bridge North is scheduled to open to traffic. This 1.2-mile-long bridge, supported by fixed columns, will carry SR 520's westbound traffic from the floating bridge to the eastern shore of Montlake. It also will extend the bicycle and pedestrian path across the lake.
The new floating bridge carries six lanes of traffic across Lake Washington.

In 2018, crews plan to break ground on the Montlake Phase, which will give rise to a partner bridge, the West Approach Bridge South, to carry eastbound traffic from Montlake to the floating bridge. This project also will construct a landscaped lid over SR 520 in Montlake to further improve connections for transit, pedestrians and bicyclists.
Looking east over Seattle's Montlake neighborhood and out to the West
Approach Bridge North, scheduled to open in late summer 2017.

Looking to the next chapters of the story, teams are actively planning for the replacement of SR 520's Portage Bay Bridge between Montlake and I-5, and adding a second drawbridge over the Montlake Cut just south of the University of Washington.

Want to learn more about the SR 520 floating bridge?
Want to know more about the new bridge? Open this online booklet to find information on the background, planning, construction and opening of the new SR 520 floating bridge.