Lacey V. Murrow Memorial Bridge, Floating road bridge on Lake Washington, Seattle, United States

The Lacey V. Murrow Memorial Bridge is a floating highway bridge built from concrete pontoons that crosses Lake Washington, linking Seattle to Mercer Island via Interstate 90. The structure consists of a series of hollow concrete boxes resting on the water surface, carrying the eastbound lanes of the highway while a second parallel bridge handles westbound traffic.

The original structure opened in 1940 as the first floating bridge across Lake Washington, serving drivers until 1990 when portions of the bridge sank during a storm. The current span reopened in 1993, following the same concept with improved concrete pontoons and reinforced anchoring systems.

Named after the first director of the state highway department, the structure honors a leader who championed floating bridge systems for the region. Drivers today cross a route that merges engineering innovation with daily commuting, carrying thousands of travelers between opposite shores of the lake.

Crossing takes a few minutes by car and offers open views of the water surface and surrounding hills from certain points. Traffic may slow during rush hours, especially during morning hours heading east and in the afternoon returning toward Seattle.

The concrete pontoons move slightly with the waves of the lake, so the roadway gently shifts when larger boats pass nearby or during windy conditions. The design served as a model for other floating bridge projects worldwide and attracted engineers from different countries seeking similar solutions for deep water crossings.