A new floating bridge was opened over Lake Washington in the US on Saturday, becoming the longest of its kind in the world.
The six lane State Route 520 floating bridge is replacing a structurally vulnerable predecessor built in the 1960's which had issues during windstorms and high waves. The new bridge will use heavier, larger and stronger anchors and pontoons to make it more robust against harsh weather conditions.
Construction of the new pontoons began in 2011, while the construction of the anchors started the following year in 2012 in Kenmore. Construction began in spring 2012 starting on the eastern shore of Lake Washington. Now completed, the bridge will be opened to public traffic in phases over the next few weeks.
It is planned that the old State Route 520 floating bridge will be dismantled by the end of this year and removed from the lake. The pontoons from the old bridge will be taken away and recycled for use in other marine construction projects.
Other benefits of the new bridge design will include an extra two lanes compared with the previous bridge, bus and carpool lanes and wide shoulders that allow vehicles to pull off the highway and avoid blocking traffic.