Floating Bridge

Since my daughter, Amy Royce and her family moved to Western Washington State, I keep coming across historic facts about the area. Of course, they were there before, but probably just didn’t grab my interest then. One such fact is that Seattle was home to the world’s first floating concrete bridge. Washington governor Clarence Martin and Lacey V Murrow, the Washington Toll Bridge Authority director, broke ground on the Lake Washington Bridge in December of 1938. The Lake Washington Floating Bridge was also known as the Mercer Island Bridge, it spanned Lake Washington from Seattle on the west to Bellevue to the east. The bridge was renamed Murrow Bridge in honor of Lacey Murrow in 1967. The bridge was a project financed by the Public Works Administration to give work to unemployed Washingtonians and to make the towns across the lake from Seattle more accessible to suburban development.

When the finished bridge opened in 1940, the Seattle Times called it “the biggest thing afloat.” It’s hard to imagine that 100,000 tons of steel, could float on more than 20 hollow concrete pontoons, and carry 5,000 cars per day. By 1989 the number of cars grew to 10,000 cars. Since the bridge would become such an important road between the two cities, the flood of November 1990 was especially devastating, in that it completely destroyed the bridge. While the bridge was closed for repairs, construction workers punched giant holes in the pontoons that kept it afloat and went home for the weekend. A few days of rain and high winds filled the pontoons with water, and the broken bridge sank.

This would not be an easy fix. As the pontoons filled with water and the bridge sank, it pulled about a half a mile of highway into the lake. There was simply no way to fix it. The bridge would have to be rebuilt from scratch. In the end, it would take three years to rebuild at a total cost of $93 million. When the bridge reopened, it would complete the coast to coast Interstate 90. On this day, September 12, 1993, the rebuilt Lacey V Murrow Bridge opened. This bridge was the east bound lane of I-90 from Seattle to Bellevue. The westbound lane is on the Homer M Hadley Bridge, which was not destroyed by the flood.