https://en.wikipedia.org/wiki/Evergreen_Point_Floating_Bridge
The new Evergreen+Point+Floating+Bridge is certainly an improvement over the old bridge.
https://seattletransitblog.com/2008/02/25/eight-lane-520
https://www.seattletimes.com/opinion/eight-lanes-for-the-520-bridge The 520 Bridge should have been designed to eventually have 8 lanes. Then in addition to having 2 general lanes each way, there not only could have been the 2 HOV lanes, but also 2 bus lanes.
At this point of the bridge is a remnant of what could have been an 8 lane section. https://www.google.com/maps/place/Evergreen+Point+Floating+Bridge
https://jfdatalinks.blogspot.com/search?q=Evergreen+Point+Floating+Bridge
