More tunnels cost more $$$- something that our current Pentagon economy hates, with people as Cary Moon being the distracting elements.

If there was a truly integrated decision-making process, than the state, King County, Seattle, and the multi-county Sound Transit would all be considering a plan together - and perhaps including big land use decision-makers like those involved with rezoning South Lake Union and Interbay, developing affordable TOD housing In Ballard and at Convention Place and Yesler Terrace, and the Seattle Center.

In this dream world, I believe, the only tunnel expansion planning for downtown would be for the existing 3rd Ave transit tunnel - sending a tunnel north/northwest from Westlake. Greg’s idea of linking the SR 99 and Battery Street Tunnel to a downtown tunnel is a good one - it just shouldn’t involve more car capacity.

Demolishing a major highway is a way of a making a statement. It is a pledge to reduce our personal vehicle use and start being smarter about our travel throughout the city.

Plus, your idea is INSANELY expensive. Build a SECOND tunnel through downtown. Hmmm, here’s a concept, why dont we just start USING the one thats already there. Take the bus. Take light rail (in a few years). If we get people to do that I think we can save the money from the tunnel and pump it into making that waterfront beautiful.

“The viaduct can be carefully removed, parts retained for viewing and concert platforms”

THAT is a great idea though. I would love for them to keep sections of the Viaduct intact, for example, the off-ramp at 1st and Spring. How awesome of a viewing spot would that be.

100 years ago, our city engineer faced the basicly the same issues. Overlooked in the hard and fast stands taken by many parties involved, I think the most pragmatic potential solution has been overlooked.

Rather than replicate the current route, l would implore that all parties review R.H. Thompson’s solution still used by used with great success by the Great Northern railroad, and still used by it’s successor today.

The idea starts at the north end of the current Battery Street Tunnel.

Where SR 99 turn west to enter the Battery Street Tunnel, begin digging a tunnel due SOUTH from that point. The Incline would begin at the current highway level, and drill down to the level of the BNSF tunnel, as this new tunnel followed directly under the exsisting surface streets SOUTH under 6th to Westlake, then deeper still south under about 5th. You keep digging down as you go to get under the current Metro bus/light rail tunnel, then level out and pop out EAST of the existing BNSF Rail Tunnel near Main Street, between 4th and 6th Avenue.

You would build two main tunnels, 3 lanes wide each with a third service tunnel between… by following under the streets, there is no domain issues.

Exit out on the Metro Bus only lane… or east of it… and parallel with sixth avenue.
Then build exit on ramps:
-One funnels back on to I-5 south,
-One funnels east to join I-90 eastbound
-One continues on to Spokane Street or angles across the industrial area to East Marginal Way
-One last ramp that funnels into the parking for the stadium area.

When tunnel and ramps are done, then break through the wall at the Battery Street Tunnel and connect the existing 99 to the new tunnel under Seattle.

The remaining Battery Street tunnel is converted into an on and off ramp that feeds back around to the waterfront, or betteryeat, a direct ramp for Piers 90 and 91 access via Western and Elliott to get to the new ship piers, and expidite interbay traffic.

ONLY THEN do you and tear down the viaduct.

• You loose the Seneca ramp, and Western Northbound, and the 1st Ave ramp southbound… but you gain faster and direct access to I-5, and you don’t have to shut down the existing viaduct for a long period of time in order to build it.
• The port gets the land adjacent to the piers from 36 south… BNSF and the port can now load ships direct to rail. Old 99 could be moved parallel to First Avenue, and reconnect with the new diversion between Lander and Spokane Street.
• The viaduct can be carefully removed, parts retained for viewing and concert platforms… and the sea wall can be replaced a block at a time to keep the waterfront working and functional…
• Best of all, Seattle gains the waterfront for parks, parking, street cars, etc, as well as a much faster second north south arterial, whose clogs bypass the city, the port gets a very efficient way to move containers.

MY guess is that this tunnel in THIS location would be far cheaper to build than anywhere along the waterfront.