SEATTLE -- Wednesday was a historic anniversary in the Seattle area as it marks 25 years since the I-90 floating bridge sank to the bottom of Lake Washington.
You may remember the floating bridge was made up of concrete pontoons. Prior to the disaster, engineers removed the pontoon's watertight doors so they could work on the bridge. But when a storm arrived on November 25, 1990, the wind-driven water from the lake flooded the pontoons, causing the bridge to sink.
Thankfully, prior to the collapse, construction workers who were working on the bridge noticed it was starting to sink. A few workers were on the bridge when it was going down, but no one was injured or killed.
The then newly opened bridge next to the one underwater did suffer some damage to its anchor cables; because of that, traffic was stopped for a few days.
The cost of the disaster was $69 million.
