Quote:
Originally Posted by chowhou
Hard disagree there. The First Narrows is actually quite shallow at approximately 50 feet at the deepest point. For reference, the Fraser at the Massey Tunnel is about 40 feet deep with the road surface at 72 feet deep.
My road/transit fantasy has always been similar to yours. The Parks Board has always been antagonistic towards the Stanley Park Causeway so why not tunnel it beneath both Stanley Park and the First Narrows? Not only that, start the tunnel at Lost Lagoon, and continue it all the way to Highway 1 in West Vancouver on the east side of the Capilano. If we do that we can hopefully demote Taylor Way from being part of highway 99 and get people wanting to go between downtown and the Upper Levels off the local roads. Build a 4 way interchange at Marine Drive in the existing space used for the 3 way interchange, and build a 3 way interchange in the unused space above Highway 1 east of the Capilano. Simply keep the existing lanes of W Georgia for the tunnel, 4 general traffic lanes with 2 bus lanes.
Then, the RoW for the causeway can be repurposed into a Skytrain RoW that will use the Lionsgate for the crossing. Keep it elevated and pedestrians/cyclists will be able to cross beneath the guideway without restriction. The grade might be a little aggressive on the southbound approach though.
|
I went and checked out some bathymetry for the First Narrows. You might be right. It wouldn't be, you know, easy, but it might be doable.
People often say "tunnel under the inlet" east of the narrows like it's just that simple, but it gets pretty deep in the harbour. The Narrows, that might be doable. Building and integrating the exit portal on the North Shore side might be a mess, though. Plus, no idea how the ground conditions play into it there.
Can't imagine the construction process would go so well as to not affect the shipping traffic, either. Like, the Deas Island/Massey crossing, they sink the tunnel into some nice gooey riverbed. Here, you can't really sink it without getting in the way. And I have a sneaking suspicion the sea floor in the narrows is rocky. TBM job, I reckon? Through what I imagine is unforgiving material. It'd be a feat.
I'd love the idea though, and we're in a fantasies thread, so, fuck yea! Tunnel!
I like that your fantasy agrees with mine here, in that the cars get the tunnel, while the train gets that sweet, sweet Bridge crossing. The scenery out the SkyTrain window crossing the LGB? Fuck, the train would be worth it for the tourism flex alone.
I still worry that, with an easy-flowing road crossing at First Narrows(be it bridge or tunnel), we still have to contend with where that traffic goes on the Downtown side. North Shore, easy, run it north to the Freeway. Your integration plan there, that's sound as a hound.
South? Dumping freeway-volume traffic into the Granville Peninsula and urban core is exactly the problem we sought to avoid when cancelling the downtown freeway project. Like, the traffic nightmare of the LGB as it currently exists is almost a feature in that it means downtown isn't choked to death any more than it already is.
I guess keeping it 4 regular-traffic lanes keeps things mostly in check, but I do think we'll need to come up with something to keep things moving downtown to handle all the new volume. And... well most of my infrastructure fantasies in the urban core tend not to involve road traffic. I reserve my road dreams for the outskirts, generally. So I've got nothing here.