On Seattle's Alaska Way Viaduct that completely disconnects the Emerald City from the Sound:
Seattle, which has been told by Governor Christine Gregoire that the state will demolish the Alaskan Way Viaduct in 2012 regardless of whether an alternative to it has been agreed upon. Voters have rejected two plans — one for a tunnel, the other for a new, larger viaduct that would put more of the waterfront in shadow.
In late June, the Seattle Post-Intelligencer reported that officials were considering eight options: “two elevated highway replacements, two tunnels, three options dispersing viaduct traffic onto surface roadways and one option referred to as ‘the trench.’”
Ya know Seattle, there's a pretty good example of how to do it Just down I-5:
The Python Grip: