The first pontoon for the SR 520 floating bridge came through the Ballard Locks on Saturday. The next one is expected to come sometime this evening.
In case you missed the live action view last Saturday, the Washington State Department of Transportation created a time-lapse video of the first pontoon for the SR 520 floating bridge going through the Hiram M. Chittendem Locks.
As you can see, the pontoon is a tight squeeze for even the large lock, which is 80 ft in width and 825 ft in length. The pontoon is 75 ft in width and 360 ft long, giving only about a 2 1/2 foot clearance on either side! It's hard to imagine that this process will be repeated 76 more times.
The next pontoon is expected to come through sometime this evening.