Ottawa Rapid Transit Network developments

[lrt's friend]

And to think if we someday want to build another subway, say along Bank Street, it will have to be even deeper.

[MalcolmTucker]

^ It could go higher, since the other is so so low!

[Kitchissippi]

The water level of the Ottawa river is about 40 metres below downtown, and is only 11 metres deep. If a Bank Street Subway were to be done beneath this tunnel, it could easily cross the river and go across to Gatineau

[blackjagger]

Originally Posted by Kitchissippi

The water level of the Ottawa river is about 40 metres below downtown, and is only 11 metres deep. If a Bank Street Subway were to be done beneath this tunnel, it could easily cross the river and go across to Gatineau

Stop your rational logic based thinking. You can't put a subway under a river, it will fill up with water. Why would we want to send a subway across the river anyways? It’s not like there are national museums, parks and tourist stops or a high concentration of jobs over there.

Cheers,
Josh

[p_xavier]

Originally Posted by Richard Eade

Thus the depth of the tunnel is really being dictated by the positioning of the stations. Had the station locations been chosen differently (say, based on what was under ground) then the tunnel could be less deep. As it happens, the east end of the Downtown-East Station will be roughly 43 metres deep; or approximately 12 stories underground.

But how can you have a tunnel that costs 3 times as more for 1000 users? These users deserve the best service the BEST.

It's the same reason that we have 180m long stations instead of 120m long with light metro. It was just fixed in advance and not properly studied for a cost perspective.

[p_xavier]

Originally Posted by lrt's friend

And to think if we someday want to build another subway, say along Bank Street, it will have to be even deeper.

The only thing I'm sastisfied about the changes is that there's now an entrance on Bank, which wasn't in the first draft of the stations.

[Franky]

Originally Posted by RTWAP

Thank you so much for that.

So the options would seem to narrow down to deep TBM tunnel, shallower TBM tunnel with constricted routing, or cut & cover.

I wonder what kind of risks and mitigation would be required to do cut & cover next to building foundations, in the middle of a mess of underground services, and with active businesses and buildings opening onto the construction site. Having done some relatively narrow trenches for their service renewals on Bank Street, the city may not feel comfortable pushing the limits on narrow streets with heavy buildings.

Don't they do this all the time to fix sewers? Plus, if the rock is already blasted and fractured, it should be easier to remove?

[Richard Eade]

Well, for fun I thought I'd see how much the tunnel could be raised if the three downtown stations were moved a bit to the west. Here is the result, shown in light blue:













The station which moves the most is the Downtown-East Station, followed by the Rideau Station. I could have moved the the Downtown-East Station to the east, but it would have then been farther from Bank, which I think is an important pedestrian street. Also, the Rideau Station can't be moved east because of the curve so moving Rideau west consolidates the gap between stations to the length between Rideau and Campus Stations. (I am not sure why they drew the Rideau Station smaller than the other underground stations - I corrected that.)

Personally, I would still put the Downtown-West Station diagonally under the new Central Library and come straight along Slater from LeBreton instead of doing the curves under Old Wellington at high speed.

So, in general, it should be possible to raise the tunnel and stations by about ten metres just be moving the station locations. A side benefit is that the Rideau Station moves farther west so there could be justification to add another station at Laurier (under Waller).

[GoTrans]

Originally Posted by blackjagger

Stop your rational logic based thinking. You can't put a subway under a river, it will fill up with water. Why would we want to send a subway across the river anyways? It’s not like there are national museums, parks and tourist stops or a high concentration of jobs over there.

Cheers,
Josh

What do you mean you can't put a tunnel under the river? Think of Montreal, London, Paris, New York, Detroit-Windsor? I seem to recall that they all have rail tunnels under rivers. The only thing that is filling full of water is the fictional facts that are sometimes portrayed here.

[Richard Eade]

Originally Posted by GoTrans

What do you mean you can't put a tunnel under the river? Think of Montreal, London, Paris, New York, Detroit-Windsor? I seem to recall that they all have rail tunnels under rivers. The only thing that is filling full of water is the fictional facts that are sometimes portrayed here.

I think blackjagger was just joshing.

[Dado]

One problem with the written word is that sarcasm sometimes gets missed.

[Aylmer]

I think that is the sarcasm smiley.

[blackjagger]

Little bit of a josher and not much of a smilie man.

I think a Bank St subway from Billings Bridge to Hull would be the best first stage of a truly Urban transit system combined with local tram/street car routes and our current/planned commuter LRT plan.

Cheers,
Josh

[Richard Eade]

Originally Posted by blackjagger

Little bit of a josher and not much of a smilie man.

I think a Bank St subway from Billings Bridge to Hull would be the best first stage of a truly Urban transit system combined with local tram/street car routes and our current/planned commuter LRT plan.

Cheers,
Josh

Unfortunately the visionaries at City Hall missed that opportunity when they didn't drop precast tunnel segments under Bank while they were rehabilitating it. They were digging below the lowest utility and they are going from Wellington through the Glebe. (Subway from Landowne to downtown anyone?) Such a lost chance. But that's what happens when no-one there is looking at the big picture.

[MalcolmTucker]

^ The marginal cost of doing that for a future unplanned subway would be so huge, and maintaining just empty boxes underground is crazy expensive.

[lrt's friend]

At some point, a Bank Street subway will need to be considered since we already know that not everything is going to fit into the east-west tunnel especially if we ever hope to extend rail into Gatineau.

We are also not considering the real need for surface rail on Albert and Slater especially with decisions that place the tunnel 12 storeys deep. OK for suburban commuters perhaps, but not good for people travelling shorter distances. Of course, this just starts looking too much like part of the abandoned plan. The politicians need to save face.

You know, given the pace we are progressing at, we could have had a working LRT system in this city today, and still have not delayed the tunnel work one bit. Somehow, I think we would have ended up with more federal and provincial funding if we had not cancelled the last plan.

[RTWAP]

Originally Posted by Richard Eade

..

That seems like a very viable, and cost effective alternative.

Do you have a map of the entire downtown area showing the route and station locations for the city's plan versus your plan? That would be nice to see.

[Richard Eade]

Originally Posted by Sir.Humphrey.Appleby

^ The marginal cost of doing that for a future unplanned subway would be so huge, and maintaining just empty boxes underground is crazy expensive.

You seem to have totally missed the point: There should be a TOTAL PLAN so that opportunities like this could be taken advantage of.

Right now there is worry about how transit is going to serve Lansdowne. If there were a subway under Bank then it wouldn't be an issue.

As for the marginal cost; the work that was done was about $25M per year. If a tunnel had been added, it definately would have cost more, but even if it had cost $100M per year (which should be a wild exageration) then so far we would have twin tunnels from Wellington to the 417 for the cost of $225M more - which is much cheaper than boring it out later. Side stations could be added as opportunities presented themselves. i.e., when a new building was built, it could tie into the shallow line. Other stations could be added under the sidewalk. The stations needn't be across from each other.

And if there is such a huge cost to maintaining an empty tunnel for a few years, then why would anyone ever build an active tunnel where the maintenance costs must be astronomical?

[Richard Eade]

Originally Posted by RTWAP

That seems like a very viable, and cost effective alternative.

Do you have a map of the entire downtown area showing the route and station locations for the city's plan versus your plan? That would be nice to see.

I drew over top of the City's plan so that you could see the two. My lines are in light blue, and the Staff's are in dark blue on the profile and black on the plan view.

[RTWAP]

Originally Posted by Richard Eade

I drew over top of the City's plan so that you could see the two. My lines are in light blue, and the Staff's are in dark blue on the profile and black on the plan view.

So exactly the same route, but slightly different station locations, and you raise the level of the entire tunnel? Nice.