Though deep bore tunnel proponents are declaring a 'consensus' decision ending years of process the clear facts are that these folks have been delaying the process until they could turn this project into a boondoggle exceeding the realistic funding levels provided by the Washington State legislature in 2005. This consensus is in reality nothing more than typical Seattle PC bullying tactic from desperate folks reeling from recent losses due the financial crisis, including WAMU. Don't forget also that leadership of the deep bore team includes folks directly responsible for WAMU.
Local committments for additional funding are definitely appropriate, however the project already has an initiative filed against it preceding even a request for funds from the voters. Remember that a tunnel has also been voted against. Albeit this is not the same tunnel, but, most significantly it was the deep bore tunnel proponents previous prefered option...
At big risk here is the favorability of tolling funding in this State - right now rapidly gaining acceptance due a quality and restrained rollout starting in Pierce County and looking very good for the Lake Washington corridor.
This project runs a high risk of being another Seattle Commons or Monorail type of situation and could very well create a statewide stain on the very valuable financing tool due the abusers using it.
Tolling in Seattle has numerous practical problems as well - likely you would need to toll I-5 as well and still you would have tons of traffic detouring into downtown Seattle, including the surface truck route to NW Seattle via Alaskan Way.
Delaying the start of tolling in Downtown Seattle until a regionwide freeway tolling scheme is designed makes sense.
Given the availability of an affordable alternative for Seattle (one that also brings down the Viaduct by Governor Gregoire's promised 2012 deadline) makes sense. A deep bore tunnel belongs on the table for future development, as do viaduct routes, including at least some elements of Frank Chopp's ideas.
When tolling is ready for these areas, then it will be time to go forward with those projects, assuming they still rate as a State priority. Future gas prices and the success of transit advocates will have a lot to say about that, and these are unknown at this time.
In any case it is clear that the tunnel proponents themselves do not rate at all - these people need to be removed from authority.
Downtown Seattle is an international city - though these tunnel proponents call themselves the embodiment of that they are in fact parasites who risk not only the health of that City but the entire State.