On December 29, 1938, Washington Governor Clarence Martin and Director of the Washington Toll Bridge Authority Lacey V. Murrow, among other dignitaries, break ground for the construction of the Lake Washington Floating Bridge (also called Mercer Island Bridge). Work on the bridge will begin shortly. This is to be the largest floating structure in the world. The bridge will cross Lake Washington from the Mount Baker neighborhood of Seattle, span the north end of Mercer Island and reach the east side of Lake Washington south of Bellevue, opening up the Eastside to suburban development. It will carry US 10 (superseded by Interstate 90) across the lake.
The bridge opened on July 2, 1940, and in 1967 was renamed the Lacey V. Murrow Memorial Bridge.
The bridge, designed by the engineer Homer Hadley (1885-1967), floats on hollow concrete pontoons. Floating bridge technology was both ancient and quite innovative (especially the concrete part) in terms of modern bridge design.
The United States Public Works Administration financed 40 percent of the $8,854,000 cost.