Irish rail fleet and infrastructure plans

Charles Babbage

https://www.boards.ie/discussion/comment/121725190#Comment_121725190

If the Northern Line was Quad then you could run express services to Connolly or via DART Underground (if it ever exists). There won't be very many people from the airport getting off in Ballymun or Glasnevin.

Hotblack Desiato

https://www.boards.ie/discussion/comment/121746361#Comment_121746361

Shure don't we all know that Norn Iron is a "temporary little arrangement" 😯 😉

Pete_Cavan

Even if quad-tracking the Northern Line were to happen (unlikely), the level of service suggested here isn't going to be possible with an airport spur. Having trains crossing the tracks will limit frequency and create operational difficulties. If anything, a spur would undermine investment in additional tracks.

If a spur from Clongriffin is required, it could be done as light rail at much lower cost. Could make it the same system as Metrolink to utilise it's control centre, maintenance facilities, etc. Even a more basic people mover would probably suffice.

Economics101

https://www.boards.ie/discussion/comment/121759550#Comment_121759550

Any Airport spur at Clongriffin would surely have a flyover junction in the Up (city-bound) direction, so no conflicts. Totally routine, but maybe beyond the imagination of those who decide transport policy in Ireland.

Pete_Cavan

https://www.boards.ie/discussion/comment/121759585#Comment_121759585

What sort of radius would be required to allow a heavy rail train make that turn? Could add 1km of track, much of it elevated, and a wide bridge. If you wanted trains coming from further north to use the spur, you'd need another such loop. The cost of such a spur would be huge.

Anyone using DART from south of Tara Street will be able to change to Metrolink to reach the airport. If Metrolink was extended north to meet the Northern Line, that would facilitate most passengers from further north.

I know people have fantansies about intercity trains using a tunnel to go directly to the airport but I doubt intercity trains would be allowed near such a tunnel, if ever built. It needs to be used for high frequency DART services which would slow any other trains. Changing to Metrolink with it's direct routing would likely be fast than heavy rail via Clongriffin.

There would be no business case for building the spur in the most expensive way possible.

bikeman1

Pop over to Germany and you’ll see many heavy rail flyovers and underpasses all over the main cities. ICEs and Regional trains flying around the place in the middle of cities. This would be easily achieved out at Clongriffin.

Consonata

https://www.boards.ie/discussion/comment/121759989#Comment_121759989

Not without quadtracking the northern line to Clongriffin which will be massively expensive, not to mention political gelignite.

https://www.boards.ie/discussion/comment/121748460#Comment_121748460

A Dart Spur to Connolly will always be slower than a Metrolink -> Glasnevin and Dart to wherever you want to go. Hell you could concieveably have a limited amount of Cork services servicing Glasnevin when ML is complete. This could never happen with a heavy rail spur to the Airport due to there being no direct connection between the Northern line and the GSWR without reversing out of Connolly.

A rail spur from Clongriffin is not cheap if it's to be done properly. Quadtracking alone will set the project into the billions. Not to mention if you are going down this route you likely want to build the direct connection between it and GSWR for it to make any sense.

spacetweek

The more I think about a DART spur the less good an idea it seems.

If you are coming from DART West or DART Southwest, change to Metrolink at Glasnevin.

If you are south of Tara St DART or north about as far as Killester, get the DART to Tara St and change to Metrolink.

(Since it's likely Metrolink will be extended to Donabate) If you're near Donabate DART station, get the DART to Donabate and change to Metrolink.

So the spur would only be useful for people living between Killester and Portmarnock! Why are we even talking about this?

Pete_Cavan

https://www.boards.ie/discussion/comment/121759989#Comment_121759989

The existence of heavy rail flyovers/underpasses elsewhere is irrelevant. In this case, it involves connecting to a perpendicular line, which would require a large radius loop to allow trains make the turn. If you want connections in both directions (i.e. south towards Dublin and north from Drogheda/Belfast), you need two such loops. The cost of this would be significant.

As already pointed out, the spur really won't serve that many people once Metrolink and DART+ are complete. You could get the same benefit at a fraction of the cost with light rail (the cost of creating a 160m heavy rail station anywhere near the terminals would be enormous, as well as the approach). Light rail would be much easier, it could cross roads at grade and even use roadspace. Once alternatives are considered, there will be no business case for a heavy rail spur.

bk

https://www.boards.ie/discussion/comment/121748460#Comment_121748460

Sure, if we spend 10 Billion+ on DART Underground and Quad tracking, then it might work. But it certainly doesn't work as the cheap and easy option that some make it out to be, which is the point I've been making.

https://www.boards.ie/discussion/comment/121760646#Comment_121760646

If you used Metrolink trains, not only are they much smaller, but you could just reuse the Metrolink station in the airport, it would make it all much cheaper.

It could also be the start of Metro West. Of course then the conversation would be if a Metrolink spur via Clongriffin makes more sense or Donabate or Rush+Lusk. You'd need to run a study to compare the options.

I'd kind of feel like either Donabate or R+L would make more sense and then leave the Clongriffin corridor reserved for future use, either by Metro or heavy rail if the Metrolink ends up overcapacity.

bk

https://www.boards.ie/discussion/comment/121760316#Comment_121760316

This is what I struggle with too. I really don't see the logic of it with Metrolink in place.

But the idea keeps being brought up by the CEO of Irish Rail and is was included in the All Island Rail Review!

So I try and understand why it might make sense, but struggle to see it. Sure, it might be nice to have, but hardly a priority.

Economics101

https://www.boards.ie/discussion/comment/121761290#Comment_121761290

The problem is that Metrolink is likely to be so expensive that is will pre-empt funding for almost everything else in the Dublin area, including making much better use of existing assets.

Markcheese

Quad tracking is likely to be ridiculously expensive and seriously disruptive , and then you've still got to go cross country to dublin airport ..

There is a surprising amount of green space between Heuston station/ phoenix park and Dublin airport - its 10 km as the crow flys , so prob 12 ish km of a route way , with a mix of at grade ,cut and cover and viaducts . So also bonkers expensive. And not much use to the areas it cuts through..

Economics101

https://www.boards.ie/discussion/comment/121761507#Comment_121761507

How expensive and disruptive? Compared to Metrolink, say. I know you have to look at the benefits as well as the costs.

And the cross-country bit from Clongriffin to the airport should be no problem: its over ground which is so noisy form approaching aircraft that it is pretty useless for anything else.

LXFlyer

https://www.boards.ie/discussion/comment/121761507#Comment_121761507

Re the northern line, I’m going to sound like a broken record here, but perhaps would it not be better to wait and see what the results of the ongoing EU funded feasibility study into possible Northern Line expansion actually says before making such pronouncements?

It’s getting a bit tiring reading all of these pronouncements here while there is a professional engineering study being carried out which will give us a definitive answer.

bk

https://www.boards.ie/discussion/comment/121761335#Comment_121761335

DART+ and BusConnects also seem to be proceeding alongside Metrolink just fine. And both of them are very much using existing assets.

In fact Dart+ very much hinges on Metrolink also being in place and the interchanges at Glasnevin and Tara St to really work well and to get the maximum benefit from these heavy rail lines.

So what existing assets do you mean? Obviously DART Underground doesn’t exist, nor does a spur to the airport. Quad tracking might as well be a major new project given how disruptive it will be. Though as LX says, perhaps other options like triple tracking etc. will be possible, we will have to wait and see.

Of course non of these will connect Swords to the city, the 5th largest urban area in Ireland, a commuter town of Dublin, with plans for it to grow to 100,000 people.

Metrolink has to be built, nothing else makes sense.

Consonata

https://www.boards.ie/discussion/comment/121761823#Comment_121761823

Nobody is arguing about the 2.2km of rail to the airport, its the capacity improvements needed on the mainline to make this at all worth while. Quadtracking it at a minimum, and then already you're looking at a project which is likely to be even more expensive than Metrolink will be.

end of the road

extra tracking for the northern line is unavoidable, airport spur or no airport spur.

how and where and how much will have to be worked out but done it is going to have to be.

Economics101

https://www.boards.ie/discussion/comment/121763664#Comment_121763664

Are you saying that an extra 2 tracks for about 10km on the Northern line (even with land acquisition and housing replacement costs) will cost more than a much longer partly underground Metrolink, with some very complicated underground stations? Metrolink's estimated costs are in the region of €10billion, and I would take that with the same level of credibility as applies to the cost estimates for the children's hospital.

LXFlyer

https://www.boards.ie/discussion/comment/121763664#Comment_121763664

With due respect, you cannot possibly know that.

There is significant EU funding going into a study to examine the feasibility of capacity expansion on the Northern Line.

Posting throwaway comments such as the last one above is just daft to be honest - you cannot possibly come to any conclusion before we see the options that might be available, and any potential EU contributions that might be available as well.

Cookiemunster

https://www.boards.ie/discussion/comment/121764035#Comment_121764035

We have a long history of delivering transport projects on time and on budget. There is no reason to equate any transport project with the NCH shít show.

end of the road

https://www.boards.ie/discussion/comment/121764035#Comment_121764035

and for that, i'm going to call it, we will get something that is under capacity quite quickly.

never mind though, at the moment it's happening so it's water under the bridge now.

Economics101

https://www.boards.ie/discussion/comment/121764295#Comment_121764295

Yes I agree, at least as far as Roads and Transport Infrastructure Ireland are concerned. However TII has responsibility for just Road and Luas (and there is nothing actually underway i.e. approved and ready for contract, as far as LUAS is concerned. That leaves Haevy Rail and Metrolink. The former seems to be subject to the NTA, and the latter seems to be fairly stand alone, but with general policy approval from the NTA. Of course the Dept of Public Expenditure has to approve of almost every significant project.

If I have this reasonably correct, it as a bit of a dog's dinner. If TII have the skillset for large complex road projects (like Dunkettle) then they could build on this and do project management for Metrolink, and heavy rail. While TII has a lot of civil engineering expertise, for rail projects they would need to acquire skills on the electrification side of things.

What skills do the NTA have?

bk

https://www.boards.ie/discussion/comment/121764468#Comment_121764468

65 meter Metro at 90 second frequency is 2.4 times more capacity of a DART every 10 minutes. It will be plenty of capacity.

GerardKeating

https://www.boards.ie/discussion/comment/121766243#Comment_121766243

But do we think it will be a 90 second frequency.

Given the same frequency, the DART would have more capacity.

L1011

https://www.boards.ie/discussion/comment/121766277#Comment_121766277

90 second frequency is implausible on heavy rail

Its even more implausible on a spur.

GerardKeating

https://www.boards.ie/discussion/comment/121766281#Comment_121766281

Maybe, but ThamesLink manages 24 tph in the core sections at peak times, which is every 150 seconds...

bk

https://www.boards.ie/discussion/comment/121766277#Comment_121766277

Metrolink is being designed to a 90 second frequency. It is in the design docs.

Now it likely won't open to that frequency, most likely 3 minutes, but it is being specced for that.

DART absolutely can't do that frequency, it can only be done with fully automated systems. Which is why Metrolink is being designed for fully automation, like Copenhagen.

DART could maybe do 5 minutes, perhaps at a stretch even 3 minutes (but not on a branch line obviously). At 5 minutes, Metrolink would still have 1.2 times the capacity, at 3 minutes frequency, yes DART would beat it with 20% more capacity.

However the cost of doing that would be a lot more then using Metro, much bigger stations for 180 meter DART's , etc.

This is why these sort of fully automated Metro systems have become so popular for new builds in mid sized European cities. They give you relatively very high capacity at a lower cost then with a traditional heavy rail system. Yes, heavy rail can potentially beat the capacity, but at much higher cost and arguably mid sized European cities don't need quiet that high capacity. The likes of London, Paris, etc. of course need it, but not the likes of Dublin, Copenhagen, etc.

LXFlyer

https://www.boards.ie/discussion/comment/121766342#Comment_121766342

The Thameslink core is under a completely automated signalling system where drivers just open/close doors and do not drive the trains.

Hardly comparable with the rest of the network which has completely different signalling.

end of the road

https://www.boards.ie/discussion/comment/121766243#Comment_121766243

plenty of capacity at first perhapse.

going forward i'm not quite so convinced due to it's definite success and growth going forward.

as i said it's water under the bridge now as it's what we are getting but i can hear complaints along the lines of the luas overcrowding issues.