The longest floating bridge in the United States can be found in Washington State. The Evergreen Point Floating Bridge, also known as the SR 520 bridge, spans 8,942 feet (2.7 km) and connects Seattle’s suburban Eastside communities across Lake Washington. It is the world’s longest floating bridge and took five years to build.
The original bridge, built in 1963 and called the Lacey V. Murrow Bridge, was named after the state’s first highway director and was replaced by the present structure in 2016. Evergreen Point Floating Bridge is a floating concrete structure that moves with changes in water levels due to tides, currents, and winds. It cost Washington State $4.6 billion USD to construct this floating bridge, making it one of the most expensive projects of its kind in the world. The bridge has two lanes in both directions and contains 5 planes for travel. Its unique engineering features help make it both durable and energy efficient.