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Here's my one question. Is a tunnel from the 427 to the 404, with NO accesses except at the ends (a super-express) really going to be that expensive? We love repeating that excavating stations (or building ramps/accesses in this case) is what really drives up underground costs; if this tunnel only requires letting some TBMs rip and not much else, then maybe it isn't that fantastical.

Sure it's less than Ford is making out to be, but I think that's what we want. While also not a perfect transit solution without infill stations/accesses, GO buses could certainly make great use of an express tunnel, too.
 
Sunnyside said:
Here's my one question. Is a tunnel from the 427 to the 404, with NO accesses except at the ends (a super-express) really going to be that expensive? We love repeating that excavating stations (or building ramps/accesses in this case) is what really drives up underground costs; if this tunnel only requires letting some TBMs rip and not much else, then maybe it isn't that fantastical.

Sure it's less than Ford is making out to be, but I think that's what we want. While also not a perfect transit solution without infill stations/accesses, GO buses could certainly make great use of an express tunnel, too.
Click to expand...

It's still very complicated. One, you still need a lot of ventilation, and you need escape routes. You need to tunnel under the Humber and Don Rivers, with the West Don Valley being very deep. That's also a lot of cement and steel. Think about the necessary width of two three-lane tubes compared to the width of a subway tunnel. Remember too how the Scarborough Subway tunnel isn't progressing very well (a single-bore tunnel).
 
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Sunnyside said:
Here's my one question. Is a tunnel from the 427 to the 404, with NO accesses except at the ends (a super-express) really going to be that expensive? We love repeating that excavating stations (or building ramps/accesses in this case) is what really drives up underground costs; if this tunnel only requires letting some TBMs rip and not much else, then maybe it isn't that fantastical.

Sure it's less than Ford is making out to be, but I think that's what we want. While also not a perfect transit solution without infill stations/accesses, GO buses could certainly make great use of an express tunnel, too.
Click to expand...
Less than Ford is making out to be??

A simple 2-lane bus tunnel isn't going to relieve car congestion - you simply don't see that many buses on that stretch of the 401. Currently there's 14 lanes. If they have any hope of doing anything, they need to put about 10 lanes in a non-stop tunnel - perhaps with a single interchange for 400 northbound.

The ventilation requirements alone will be extreme.
 
Sunnyside said:
Here's my one question. Is a tunnel from the 427 to the 404, with NO accesses except at the ends (a super-express) really going to be that expensive? We love repeating that excavating stations (or building ramps/accesses in this case) is what really drives up underground costs; if this tunnel only requires letting some TBMs rip and not much else, then maybe it isn't that fantastical.

Sure it's less than Ford is making out to be, but I think that's what we want. While also not a perfect transit solution without infill stations/accesses, GO buses could certainly make great use of an express tunnel, too.
Click to expand...
All fun and games until there's a tanker fire with 20 km of cars backed up in a smoke filled tunnel.
 
nfitz said:
Less than Ford is making out to be??

A simple 2-lane bus tunnel isn't going to relieve car congestion - you simply don't see that many buses on that stretch of the 401. Currently there's 14 lanes. If they have any hope of doing anything, they need to put about 10 lanes in a non-stop tunnel - perhaps with a single interchange for 400 northbound.

The ventilation requirements alone will be extreme.
Click to expand...
By less, I meant less than Pickering to Milton, or Mississauga, or any additional distance really- Ford has floated this iirc. I also did not mean only for transit- you would obviously have more lanes overall. I have a hard time seeing 10 though; I personally imagined 6, in some sort of stacked configuration if you use a big enough TBM.... but @ShonTron got to that.

I will argue that buses don't use the 401 because they can't do so reliably... not because there Isn't demand for it. The 407 is further out yet gets higher use as a speedy trunk- the 401 would become this and then some.

Design-wise, I don't know what to think about the 400. The Bradford bypass should theoretically take a good amount of extra-regional traffic, but there's a lot between that and the 401.

I did just remember that you'd probably want/need to tunnel to connect the 401's two local/express sections however, so add a little distance for that too.

ShonTron said:
It's still very complicated. One, you still need a lot of ventilation, and you need escape routes. You need to tunnel under the Humber and Don Rivers, with the West Don Valley being very deep. That's also a lot of cement and steel. Think about the necessary width of two three-lane tubes compared to the width of a subway tunnel. Remember too how the Scarborough Subway tunnel isn't progressing very well (a single-bore tunnel).
Click to expand...
Well...ventilation would be needed in any tunnel scenario. The question is if that adds that much to the 'base' tunnelling cost, which as you've highlighted, faces its own challenges. I am glad you brought the subway comparison- are we talking meeting or exceeding those kinds of per-km costs, regardless of value engineering options?
--------
We do have to consider in general what Sydney NSW has managed. While more ambitious, Australian states and Canadian provinces are basically step-siblings; If they found the capacity to do it, Ontario most likely could too (unless engineering issues are that much worse...).
 
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afransen said:
All fun and games until there's a tanker fire with 20 km of cars backed up in a smoke filled tunnel.
Click to expand...
While that's an obvious big problem... as I mentioned above, this isn't the first long road tunnel ever built. Is ventilation really what tips this over the edge? I'd sooner worry about Toronto's soil and valleys.
 
I've been wondering whether the renewed support for the rail Missing Link isn't really the first stage in a climb-down (climb-up?) from the tunnel. Look folks, with all the railway corridors we built and bought for only 15 billion, we don't need the road tunnel for 50. We saved you 35 billion. We're getting it done!
 
Sunnyside said:
While that's an obvious big problem... as I mentioned above, this isn't the first long road tunnel ever built. Is ventilation really what tips this over the edge? I'd sooner worry about Toronto's soil and valleys.
Click to expand...
No but in the unlikely event that it actually happens it will be the longest road tunnel ever built. Under one of the world's widest highways with no obvious way to tie it into the existing highway system where it will inevitably cause huge bottlenecks. There's no scenario where this doesn't cost a scandalous amount of money.
 
Would you drive a tunnel that has no intermediate entry/egress points for emergency vehicles ?

There will have to be junctions of some sort at some interval. That will create cost.

- Paul
 
crs1026 said:
Would you drive a tunnel that has no intermediate entry/egress points for emergency vehicles ?

There will have to be junctions of some sort at some interval. That will create cost.

- Paul
Click to expand...
I watched daylight with sly. No I would not.
 
I did once drive tunnels in Iceland that were under mountains, they were only one lane wide with pullouts every so often to permit meets with opposing traffic. I don’t recall if they had infra for ventilation or emergency shelter. But that was in an environment where there was one opposing vehicle every ten minutes. And no fire station or ems within 20-30 miles.
I can’t imagine that one could design a tunnel to serve as relief for congestion using prevailing North American urban codes without planning for bumper to bumper occupancy and reliable emergency vehicle passage. Insurance and liability interedts would prevail, Plus, I have watched too many dump truck driving with bed raised reels lately.

- Paul
 
Once again, there is precedent for major urban expressway tunneling.

As close as Montreal to Toronto on a smaller scale.. and as far as Sydney for a project which is more functionally similar to what the 401 project would be. Sydney's motorway network includes over 40km of motorway tunnels today, including the M8 (Westconnex) which has a 22km mainline freeway with an additional 6km of connecting branches and multiple entirely underground interchanges.

Sydney is also growing this network - there is another 10km of tunnels currently under construction which will be contiguous with the M8 tunnel. This means 40kms of contiguous motorway tunnels once complete, with another 10km of tunnels in the city for a total of over 50kms of motorway tunnels.

Another thing to remember is that a theoretical 401 widening is exactly that - a widening. Tunneling will be employed where there isn't space on the surface, but that isn't to suggest that there is not any space across the entire corridor. MTO is not afraid to use expropriation where necessary and appropriate, and many parts of the 401 have more space around them than it may initially appear.

As I've repeated before - I think most agree that east-west capacity through the GTA needs to be addressed somehow - let's MTO cook and see what they come up with and judge it then.
 
Bonnie Crombie really laid into Ford regarding this tunnel at last night's debate. She threw around the number that it would cost 150 billion, take 40 years to build and bankrupt the province.
 
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