DART Underground - Alternative Routes

strassenwo!f · 14-12-2014 4:03pm

L1011 wrote: »

You go ask for them.

Or are you still unable to actual write comments to the relevant people?

Yes, still unable. I live outside the country, and I don't pay the taxes which will be used to pay for this project. It's no business of mine.

L1011 · 14-12-2014 4:07pm

strassenwo!f wrote: »

It's no business of mine.

If that's your viewpoint, I'm sure you're going to save us your tiring efforts to get it re-routed then? Good.

strassenwo!f · 14-12-2014 4:24pm

Why? It's my home town, and I want what's best for it.

Why would I not post on the World Wide Web if I think the city's current plans could be improved?

L1011 · 14-12-2014 4:25pm

strassenwo!f wrote: »

Why? It's my home town, and I want what's best for it.

Why would I not post on the World Wide Web if I think the city's current plans could be improved?

In that case, you can contact the relevant people then.

Your "I'm not going to pay for it" argument there means you really can't keep going on about costs, by the way.

strassenwo!f · 14-12-2014 4:54pm

L1011 wrote: »

In that case, you can contact the relevant people then.

Your "I'm not going to pay for it" argument there means you really can't keep going on about costs, by the way.

But the reality is that I'm not going to be paying for it,

I could understand your point of view if I, as an outsider, was trying to persuade people that a more expensive option was actually better. I'm not.

I'm trying to point out that a direct route should have lower construction costs, while also directly serving more people. What's wrong with that?

L1011 · 14-12-2014 5:02pm

strassenwo!f wrote: »

But the reality is that I'm not going to be paying for it,

I could understand your point of view if I, as an outsider, was trying to persuade people that a more expensive option was actually better. I'm not.

I'm trying to point out that a direct route should have lower construction costs, while also directly serving more people. What's wrong with that?

You're making unsubstantiated claims of cost savings that have zero impact on you; and when asked to make those claims to the people who actually matter you again say it has no impact on you.

This is utterly pointless.

murphaph · 14-12-2014 5:48pm

strassenwo!f wrote: »

I'm trying to point out that a direct route should have lower construction costs

This is simply not correct in an urban environment. The location of the station boxes is arguably much more decisive in overall cost than simply the tunnel length!!!

You have already accepted that a station box at College Green would be technically much more complex than one at St. Stephen's Green, ergo your shorter route could easily cost substantially more than the (slightly!!) longer route.

Added to the technical difficulty (due to proximity of buildings with shallow foundations and built on reclaimed swamp land) you have the cost to the economy of closing CG for a protracted period.

murphaph · 14-12-2014 6:13pm

The whole MN plan is up for review. Check the other thread about an "optimised" Metro North. IMO the extravagant station at O'Connell Bridge will never be built. These are 2 related but separate projects. Building a station box at the Green does not mean an extravagant station has to be built under the Liffey. They can easily just move that planned station slightly further north and that is that.

strassenwo!f · 14-12-2014 6:13pm

Murphaph, a reminder:

strassenwo!f wrote:

Now, with regard to station boxes, routing the interconnector through College Green and having the metro-DART interchange there would not involve increasing the number of station boxes.

The current plan in the central area (O'Connell Street to St. Stephen's Green) is as follows: two station boxes at St. Stephen's Green, and two station boxes at O'Connell Bridge. Four boxes in total. The arrangement at St. Stephen's Green would be, as I understand it, a two-level box and a three-level box, to allow one line to pass over the other. Perfectly sensible.

The arrangement at O'Connell Bridge is for two four-level boxes, each around 80-100 metres long, with the platforms adding an additional cost, because it is planned that they will be mined out under the river. In terms of manpower and materials, what is effectively being planned at O'Connell Bridge is an eight(8)-level station, before you even get to the cost of constructing any platforms.

...

What I am suggesting would effectively involve: (i) at St. Stephen's Green, a two-level station box for the metro; (ii) at College Green, a three-level station box for the metro and a two-level station box for the DART; and (iii) at O'Connell Street, a two- or three-level station box, depending on where on the street it is located.

Also a total of four station boxes.

I don't think one needs to be a quantity surveyor to see which of these options should cost more, in terms of manpower and cost of construction materials.

strassenwo!f · 14-12-2014 6:16pm

Sorry, Murphaph, I deleted my post because it didn't include all the bits I wanted to include. It seems you were replying to it while I was reposting.

L1011 · 14-12-2014 6:48pm

strassenwo!f wrote: »

Murphaph, a reminder:

You seem to have forgotten that this isn't actually possible due to the required depth of the both sets of tunnels. Tunnels aren't rollercoaster rides that can be pulled up and down depth-wise at will.

murphaph · 14-12-2014 6:58pm

Strassenwolf, of course it has fewer boxes because you have shortened Metro North with your revisions. It would not run as far as the CBD so anyone travelling in to there from Swords etc. would need to transfer on to Luas or just walk from CG. The problem is that people do actually want to get to the CBD around St. Stephen's Green, something you seem to not really understand.

If you don't shorten MN then you still need a station box for MN at St. Stephen's Green.

strassenwo!f · 14-12-2014 7:24pm

Murphaph, could you read the post again. Where am I suggesting shortening metro north?

strassenwo!f · 14-12-2014 7:28pm

L1011 wrote: »

You seem to have forgotten that this isn't actually possible due to the required depth of the both sets of tunnels. Tunnels aren't rollercoaster rides that can be pulled up and down depth-wise at will.

Yes, it is possible. The main reason for the enormous depth of the RPA's absurd plan is that you need to have a pretty much level track where you have platforms. Thus, if you're going to have platforms under the river, you need to have a level piece of track, and so you need to have station boxes of greater depth.

If you just need to go under the river, you don't need to go to such depths.

murphaph · 14-12-2014 8:08pm

strassenwo!f wrote: »

Murphaph, could you read the post again. Where am I suggesting shortening metro north?

Sorry, misread it. I still don't see how you propose fewer station boxes by running via CG. The changes to MN can (and probably will) be made independently of moving the interchange from the Green to CG.

strassenwo!f · 14-12-2014 8:17pm

Try reading it again.

I'm not suggesting that there would be fewer station boxes.

L1011 · 14-12-2014 8:20pm

strassenwo!f wrote: »

Yes, it is possible. The main reason for the enormous depth of the RPA's absurd plan is that you need to have a pretty much level track where you have platforms. Thus, if you're going to have platforms under the river, you need to have a level piece of track, and so you need to have station boxes of greater depth.

If you just need to go under the river, you don't need to go to such depths.

You're not going to make it under the river, or indeed basements in some cases with your comically close to the surface station boxes.

They're deep for a reason - reasons clearly beyond a crayon-wangler. You can't just pull them up to the surface in a desperate attempt to pretend that adding more stations - the most expensive element of the build - doesn't increase the cost vastly

murphaph · 14-12-2014 8:24pm

strassenwo!f wrote: »

Try reading it again.

I'm not suggesting that there would be fewer station boxes.

So what was your point?

My point is that CG is a technically much more difficult place to build an interchange station than the Green. Agreed or not?

strassenwo!f · 14-12-2014 8:37pm

murphaph wrote: »

So what was your point?

My point is that CG is a technically much more difficult place to build an interchange station than the Green. Agreed or not?

Agreed.

murphaph · 14-12-2014 8:40pm

And agreed that as a result the station box at CG would be more expensive than one at St. Stephen's Green, possibly significantly more expensive?

strassenwo!f · 14-12-2014 8:41pm

L1011 wrote: »

You're not going to make it under the river, or indeed basements in some cases with your comically close to the surface station boxes.

They're deep for a reason - reasons clearly beyond a crayon-wangler. You can't just pull them up to the surface in a desperate attempt to pretend that adding more stations - the most expensive element of the build - doesn't increase the cost vastly

First of all, having the metro at the base of a three-level station box in College Green is hardly comically close to the surface.

Secondly, you would be adding another station to the system map, but you would not be adding more station boxes. Instead of the RPA's plan to build two stations at one location (O'Connell Bridge), you would separate them and give greater coverage of the city by the metro.

strassenwo!f · 14-12-2014 8:54pm

murphaph wrote: »

And agreed that as a result the station box at CG would be more expensive than one at St. Stephen's Green, possibly significantly more expensive?

Agreed again.

I can't put an actual figure on it, but you would have to spend a lot of money supporting neighbouring buildings (like the front of TCD) during construction. This is something which would not be required at all in St. Stephen's Green, because you'd be building next to a park. Even though it would have essentially the same layout as the currently proposed St. Stephen's Green interchange, it would be much more expensive to build, for the reason given.

Against that, you wouldn't be building the two four-level stations at O'Connell Bridge, but would instead be building much smaller (and much cheaper) metro stations at O'Connell Street and St. Stephen's Green.

L1011 · 14-12-2014 9:01pm

strassenwo!f wrote: »

First of all, having the metro at the base of a three-level station box in College Green is hardly comically close to the surface.

When it has to make it under the river in a very short distance (and then come back up to your other effectively cut-n-cover depth station on OCS), yes, it is comical.

Your suggested station moves are going to require far more work in extracting station boxes - that is not actual arguable, as your idea that we can just pull them closer to the surface is unworkable.

murphaph · 14-12-2014 9:13pm

strassenwo!f wrote: »

Against that, you wouldn't be building the two four-level stations at O'Connell Bridge, but would instead be building much smaller (and much cheaper) metro stations at O'Connell Street and St. Stephen's Green.

The extravagant station at O'Connell Bridge can (and IMO will) be scrapped and replaced with a "standard" station or even 2 standard stations. MN is likely to see many changes if it is ever built.

Your claim has been all along that your proposed route would be cheaper, but now you readily accept that your proposed station box would be more expensive than the one at St. Stephen's Green and you claim your savings would actually come from the ability to modify another project altogether (MN), but that modification is simply not dependent on MN having an interchange station with DU at CG.

So you accept that your proposed route does not make DU itself cheaper but in fact more expensive (because the 100m or so of extra tunnel is negligible when compared to the extra engineering complexity at CG, never mind cost to wider economy due to prolonged closure) and that any theoretical savings your route might deliver would actually come from redesigning another project that could be redesigned anyway (eg, MN station on the wide Westmoreland St. and one at Upper O'Connell St, instead of the massive one under the river that will never see the light of day)?

strassenwo!f · 14-12-2014 10:36pm

murphaph wrote: »

The extravagant station at O'Connell Bridge can (and IMO will) be scrapped and replaced with a "standard" station or even 2 standard stations. MN is likely to see many changes if it is ever built.

Your claim has been all along that your proposed route would be cheaper, but now you readily accept that your proposed station box would be more expensive than the one at St. Stephen's Green and you claim your savings would actually come from the ability to modify another project altogether (MN), but that modification is simply not dependent on MN having an interchange station with DU at CG.

So you accept that your proposed route does not make DU itself cheaper but in fact more expensive (because the 100m or so of extra tunnel is negligible when compared to the extra engineering complexity at CG, never mind cost to wider economy due to prolonged closure) and that any theoretical savings your route might deliver would actually come from redesigning another project that could be redesigned anyway (eg, MN station on the wide Westmoreland St. and one at Upper O'Connell St, instead of the massive one under the river that will never see the light of day)?

I don't know how you are managing to come up with '100 metres or so' extra tunnelling. It appears the St. Stephen's Green route would be somewhere over 500 metres longer. Thus, you've got extra tunnelling costs, based on the information we have, of somewhere in the 100 million euro ballpark.

There are really two scenarios: one where the metro isn't built, and one where it is.

I would think that much of the extra cost of a College Green interchange would be accounted for by the metro part of the station, ie the bit right up against TCD. If the metro isn't built, then you would just be building the interconnector bit, and there's no reason for that to be much more expensive than the proposed St. Stephen's Green station. College Green is a nice wide location, so it shouldn't be difficult to build a station there without spending a lot of money on supporting buildings.

You certainly wouldn't be eating much into the 100 million you'd save by building a shorter route.

If the metro is built, I am suggesting that it would have a two-level station at St. Stephen's Green, a three-level station at College Green and let's say a three-level station on O'Connell Street. These latter two should allow the metro to pass comfortably under the river and should be considerably cheaper (in terms of manpower and construction materials) than what is currently proposed for O'Connell Bridge. Savings here, though, would probably be eaten up by the extra measures which would be needed to protect buildings like the front of TCD, but I'm afraid I can't put a specific figure on what the costs of such protective measures might be.

With regard to the costs to the wider economy of closing College Green for the construction period, I have already stated that I cannot say what they would be. All I can say is that there would certainly be a greater cost to the economy during construction, compared to St. Stephen's Green where construction of such a station should cause hardly any disruption.

Nor can I put a figure on the eventual benefit which would accrue to the economy from having a station with much more efficient passenger uptake and delivery (compared to building at St. Stephen's Green), at all hours of the day.

L1011 · 14-12-2014 10:52pm

strassenwo!f wrote: »

Thus, you've got extra tunnelling costs, based on the information we have, of somewhere in the 100 million euro ballpark.

No, we don't. There we are with your division of total project cost (including rolling stock, station boxes, etc, etc) by tunnel length. That isn't what the tunnelling costs.

Why do you keep trying to bring back comprehensively destroyed arguments as if they're fresh and valid? Like that, and the entire rest of your post

murphaph · 14-12-2014 11:24pm

strassenwo!f wrote: »

If the metro is built, I am suggesting that it would have a two-level station at St. Stephen's Green, a three-level station at College Green and let's say a three-level station on O'Connell Street. These latter two should allow the metro to pass comfortably under the river and should be considerably cheaper (in terms of manpower and construction materials) than what is currently proposed for O'Connell Bridge. Savings here, though, would probably be eaten up by the extra measures which would be needed to protect buildings like the front of TCD, but I'm afraid I can't put a specific figure on what the costs of such protective measures might be.

You're doing it again.

The extravagant OCB station design will not go ahead, believe me. That part of MN is dead and they will come up with a simplified design. You don't have to route DU through CG for that OCB station to be rethought. It is not a saving therefore based on routing DU through CG. Can you accept that?

The advantage of SSG is that you can quite easily excavate the ground and build the large station boxes using standard construction techniques. I don't even think a station box would fit in CG. I think you'd have to mine the DU station and possibly the MN station, if you want to achieve straight platforms. Could you please sketch the 2 station boxes (DU and MN) on a google maps image of CG from above. You can't excavate right up to the foundations of those historic buildings without incurring horrendous costs in underpinning etc. So leave a little wiggle room please.

strassenwo!f · 15-12-2014 12:18am

murphaph wrote: »

You're doing it again.

Doing what again? Are you talking about L1011's comment above?

If so, he's been on about this for ages, and doesn't appear to be able to use a calculator. If you were simply to divide project cost (2 billion) by tunnel length (7.6 km), you would come up with a figure of 263 million per kilometre. I have always been working on a basis of 200 million per kilometre for tunnelling costs, ie way below what you'd get by simple division.

If you've got a more accurate figure of what Irish Rail think the actual tunnelling costs will be per kilometre, let's use that.

murphaph wrote: »

The extravagant OCB station design will not go ahead, believe me. That part of MN is dead and they will come up with a simplified design. You don't have to route DU through CG for that OCB station to be rethought. It is not a saving therefore based on routing DU through CG. Can you accept that?

An Bord Pleanala didn't appear to have any problem with that station, but of course their appraisal of both projects does seem to have been quite gentle. And the RPA appear to still believe that it's going to happen. You, apparently, know better.

In any case, if it is redesigned, and you still have to have stations at St. Stephen's Green and O'Connell Street, and Trinity itself has been ruled out, surely routing via College Green is an obvious option?

murphaph wrote: »

The advantage of SSG is that you can quite easily excavate the ground and build the large station boxes using standard construction techniques. I don't even think a station box would fit in CG. I think you'd have to mine the DU station and possibly the MN station, if you want to achieve straight platforms. Could you please sketch the 2 station boxes (DU and MN) on a google maps image of CG from above. You can't excavate right up to the foundations of those historic buildings without incurring horrendous costs in underpinning etc. So leave a little wiggle room please.

I shall certainly do this, but I'm afraid I don't currently know how.:o Any advice would be welcome.

In the meantime, as I said above, the easy part of a College Green would be the Dart station, as you would have plenty of room (6 lanes of road, in parts, plus a central median, in parts) to work with. A north-south metro box would be unquestionably a much tighter proposition.

murphaph · 15-12-2014 12:32am

But they have to at least allow for MN at some future point in time, so any station at CG must accommodate both.

strassenwo!f · 20-12-2014 2:38pm

I have a picture for the board, in answer to recent questions, but I'm having difficulty uploading it. What's the best way to upload it to the thread?

(I've tried things like imageshack and stuff, but it still comes up as a sort of an icon, rather than a picture)

DART Underground - Alternative Routes

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