DART+ (DART Expansion)

antoinolachtnai · 22-09-2015 11:14pm

Howth and Malahide are really outer towns and the lines there run through countryside. The Oslo lines seem to go through populated areas for almost their entire lengths.

There is no plan to ever do what you describe and DU is not designed to do it. The only plan for extending the DART network is through more open countryside to places like Drogheda and Maynooth.

There is already the makings of an Oslo-style ring in Dublin. The problem is that DU wouldn't really open it up.

Brian CivilEng · 22-09-2015 11:22pm

antoinolachtnai wrote: »

Howth and Malahide are really outer towns and the lines there run through countryside. The Oslo lines seem to go through populated areas for almost their entire lengths.
.

On the contrary, the outer lines in Oslo pass through farmland. Once you get out of the city Oslo feels much more lower density than Dublin.

It is actually very similar to what could happen in Dublin. The lines overlap not just in the central tunnel but a fair bit on the surface as well, the fingers only split in the suburbs.

It's late now, I'll write more of a description of the Oslo system another time.

An interesting tidbit though, originally the lines on the east had a different loading gauge and power supply to the lines on the west. So they all would terminate in Nationaltheatret and you would have to walk between the lines to transfer.

plodder · 22-09-2015 11:25pm

liam24 wrote: »

This is such a dim question that you must be in the cabinet. Paschal, is that you?

I don't think it was a dim question. It confirms my view expressed a few pages ago that people never got what it was about. I think Irish Rail could have done a better job of selling it to the public.

liam24 · 22-09-2015 11:32pm

plodder wrote: »

I don't think it was a dim question. It confirms my view expressed a few pages ago that people never got what it was about. I think Irish Rail could have done a better job of selling it to the public.

It wouldn't be a dim question if my mother, who has no interest in such things, asked me. It is dim if you come on a forum about Dart Underground and argue against it without seemingly having done any research on it whatsoever.

Brian CivilEng · 22-09-2015 11:34pm

plodder wrote: »

I don't think it was a dim question. It confirms my view expressed a few pages ago that people never got what it was about. I think Irish Rail could have done a better job of selling it to the public.

I always thought that once Transport 21 was announced, the public transport map for Dublin should have been redesigned around the plan. Every map should have showed the final network with the unbuilt lines greyed out. That would have made everyone understand what was going to happen, and kept the plans in the public conscience.

Anyway, if anyone knows which consultant gets the job for redesigning the underground let me know because I want to drop my cv in. Reading about the plans for the interconnector and rail link to the airport in the 90's were what made me study Engineering and Transport Planning and the first place.

Brian CivilEng · 22-09-2015 11:36pm

liam24 wrote: »

It wouldn't be a dim question if my mother, who has no interest in such things, asked me. It is dim if you come on a forum about Dart Underground and argue against it without seemingly having done any research on it whatsoever.

It was not a dim question. I had to explain how the dart underground would work to other engineers when I worked for a company bidding on some related work.

Grandeeod · 22-09-2015 11:39pm

plodder wrote: »

I don't think it was a dim question. It confirms my view expressed a few pages ago that people never got what it was about. I think Irish Rail could have done a better job of selling it to the public.

The project was never sold well by Irish Rail beyond very expensive Sunday Broadsheet supplements. In fact prior to 2005, a voluntary effort promoted it to a much better degree to both the public and politicians. Once it was included in Transport 21 and became Government policy the voluntary effort was wound down. However after 2011 and with the incoming FG lead Government a gap appeared and wasn't filled by the original voluntary effort due to certain people moving on.

In the mid 2000s there was a dedicated extend the DART website and an explanatory flier doing the rounds. There were also public meetings in various areas related to the DU project. This was all voluntary and had a positive media and political reaction.

antoinolachtnai · 22-09-2015 11:43pm

It is a cross design, basically the opposite of the spine design of Oslo (and Munich, and Frankfurt and many others)

It creates one high capacity line, not two. The Clonsilla/Dun Laoghaire line isn't very high capacity, because of the level crossings.

The high-capacity line won't have very many services though. It won't use any more than a fraction of the capacity available in the tunnel.

Each line has an inland leg (high density) and a seaside leg (low density). It is a crazy way to design a system.

Added to that, only one of the lines has a really strong destination (St Stephen's Green). Pearse St and Docklands are office destinations only. St Stephen's green is multifaceted and will get traffic at all times from all directions. This can cause all sorts of problems. The Oslo system (and other similar spine systems) avoids this by running all the trains through the main stations.

Thargor · 23-09-2015 12:45am

liam24 wrote: »

It wouldn't be a dim question if my mother, who has no interest in such things, asked me. It is dim if you come on a forum about Dart Underground and argue against it without seemingly having done any research on it whatsoever.

Probably not even worth replying to someone so far up their own ass but for everyone elses sake I have been watching this for years, the only destination of any interest is Stephens Green, comparisons to Oslos lines are ridiculous, there is feck all places left in Dublin that are a pain to get to and the places that are werent even being targeted by DU. If there was no LUAS then spending billions tunneling under Dublin from Heuston would be a good idea.

murphaph · 23-09-2015 7:10am

Still it seems many don't get it, even in this thread.

plodder · 23-09-2015 7:12am

liam24 wrote: »

It wouldn't be a dim question if my mother, who has no interest in such things, asked me. It is dim if you come on a forum about Dart Underground and argue against it without seemingly having done any research on it whatsoever.

Welcome to democracy.

Bray Head · 23-09-2015 9:29am

antoinolachtnai wrote: »

It creates one high capacity line, not two. The Clonsilla/Dun Laoghaire line isn't very high capacity, because of the level crossings.
.

In the scheme of a €4bn spend, sorting out a few level crossings is not a big deal.

You would need to put in an ugly bridge or tunnel at Merrion Gates and one more in Sandymount. It would be expensive and disruptive but the main impediment would be the angry locals.

The Bray Level crossing does not carry much traffic and one crossing in Merrion/Sandymount/Ballsbridge and another and Merrion Gates would probably be enough for traffic.

Captain Chaos · 23-09-2015 9:35am

antoinolachtnai wrote: »

Howth and Malahide are really outer towns and the lines there run through countryside. The Oslo lines seem to go through populated areas for almost their entire lengths.
.

The DART lines from Howth Junction to Howth and Malahide are not countryside or green belt areas at all. They are built up all the way with industrial estates and high density housing and apartment blocks all the way.

They are not outer towns at all.

Carawaystick · 23-09-2015 9:47am

Captain Chaos wrote: »

The DART lines from Howth Junction to Howth and Malahide are not countryside or green belt areas at all. They are built up all the way with industrial estates and high density housing and apartment blocks all the way.

They are not outer towns at all.

It's green fields all the way from Clongriffin to Malahide

I can't see what the DART would bring to Balbriggan, that dmu trains cant?
DARTS would be slower, stopping at more stops on the way Kilester, Kilbarrack etc
Darts have less seating
Darts have no luggage racks
Darts have no toilets
Darts have no tables

plodder · 23-09-2015 9:51am

Captain Chaos wrote: »

The DART lines from Howth Junction to Howth and Malahide are not countryside or green belt areas at all. They are built up all the way with industrial estates and high density housing and apartment blocks all the way.

They are not outer towns at all.

It's certainly high density as far as Clongriffin, with smaller amounts in vicinity of Portmarnock DART station, and what isn't developed has potential. It's extraordinary that what amounts to good forward planning, is criticised today for being over engineered, knowing that the alternatives will likely be congested very quickly.

Heartbreak Hank · 23-09-2015 10:01am

From Iarnród Éireann's 2030 Rail Network Strategy Review Final Report October, 2011

"Phase 3: 2020-2025: Electrification of the Core Rail Network

When sufficient growth has occurred and rolling stock replacement is approaching, electrification of Dublin-Galway and Dublin Cork will yield significant returns. This should encompass direct services to Dublin City Centre and Dublin Airport via the DART Underground."

Presumably, this would also allow Cork - Belfast trains if the full Northern Line was electrified also so there would be a national benefit - not just a Dublin-centric one. Granted all that could be hundreds of years away.

McAlban · 23-09-2015 10:06am

I often visit Oslo on business, and stay in the Scandic at Oslo S because I can get around the city easily from there.

Oslo also has the flytoget HSL from Airport to Oslo S. 30 Minutes from Baggage Claim to Oslo S, (a 45km Journey, think Pearse to Drogheda) Quick interchange down an escalator and across a couple of platforms, then another 12 Minutes to our local office by Metro. It does cost about €30 but that's the Oil Related inflation in Oslo for you (a pint can set you back €12).

Irish People just don't get it. A lot of People think the Luas Red Line is a Drug Den/Bar/Living Room/Toilet to sit in while it transports you to Town.

DART to Balbriggan is useless without DU. The Clongriffin Spur is useless without DU. KRPII, Maynooth Line Electrification etc etc. All a waste of money without DU.

Bray Head · 23-09-2015 10:12am

plodder wrote: »

It's certainly high density as far as Clongriffin, with smaller amounts in vicinity of Portmarnock DART station, and what isn't developed has potential. It's extraordinary that what amounts to good forward planning, is criticised today for being over engineered, knowing that the alternatives will likely be congested very quickly.

It is not built on because it is under a flight path into a busy airport.

Believe me, having lived under a wide-body flight path, this is one of few places where Irish planners have got it right.

plodder · 23-09-2015 10:36am

Bray Head wrote: »

It is not built on because it is under a flight path into a busy airport.

Believe me, having lived under a wide-body flight path, this is one of few places where Irish planners have got it right.

But, the runway is over 6km from the rail line. There are zones close by where development is prohibited all right, but planes are so much quieter nowadays, it's not the same problem as it used to be. Though granted the DAA will see plenty of opposition when they resurrect their 2nd runway plan. But sin scéal eile.

cgcsb · 23-09-2015 11:12am

random_guy wrote: »

Drive into a dead-end, park train, walk to the far end, restart train, drive off for the return journey. I can imagine it will do wonders for capacity...or not.

I presume a loop is intended as someone above mentioned but it still does nothing for line capacity.

Someone above also asked if there is a turning loop like that in place anywhere else and I'm nearly sure that Schwabstrasse in Stuttgart has one where 3 of the 6 lines use that. But then again, it is part if the bigger picture.

Openrailwaymap.org will reveal all.

but for the cost of an underground turn around would it not be cheaper/the same price to just continue the tunnnel an extra 1km to Docklands as planned.

salmocab · 23-09-2015 11:14am

The Indo today mentions that electrification to hazel hatch is still on the cards, how will that work? where would it run to assuming its the dart will it go through the Tunnel in the Phoenix park

cgcsb · 23-09-2015 11:25am

We'll probably see a DART line from Kildare-Heuston, entirely separate from the rest of the DARt network. Electrification through the PPT would be a feat of engineering on it's own

Carawaystick · 23-09-2015 11:28am

Bray Head wrote: »

It is not built on because it is under a flight path into a busy airport.

Believe me, having lived under a wide-body flight path, this is one of few places where Irish planners have got it right.

The Outer Marker Beacon on the road form Baldoyle to Portmarnock shows the centre line of the runway
The gap between Portmatnock and Baldoyle is mainly south of this, so this is not the reason for the gap. (greenbelt)

loyatemu · 23-09-2015 12:10pm

cgcsb wrote: »

Electrification through the PPT would be a feat of engineering on it's own

I'm not arguing against DU, but I'm sure the PPT can be electrified for a lot less than building a new tunnel.

Banjoxed · 23-09-2015 12:21pm

salmocab wrote: »

The Indo today mentions that electrification to hazel hatch is still on the cards, how will that work? where would it run to assuming its the dart will it go through the Tunnel in the Phoenix park

The day the Indo has a scooby-doo about anything to do with Public Transport is the day it will vanish in a mist of contradiction.

antoinolachtnai · 23-09-2015 12:30pm

plodder wrote: »

It's certainly high density as far as Clongriffin, with smaller amounts in vicinity of Portmarnock DART station, and what isn't developed has potential. It's extraordinary that what amounts to good forward planning, is criticised today for being over engineered, knowing that the alternatives will likely be congested very quickly.

It is hard to see why anyone would consider running a DART out to Balbriggan when an area like Blanchardstown is so underserved.

plodder · 23-09-2015 12:39pm

antoinolachtnai wrote: »

It is hard to see why anyone would consider running a DART out to Balbriggan when an area like Blanchardstown is so underserved.

Yes. I'm not sure I see the point either. It already has a reasonable train service. It's more important to create new branches of the "network" than to extend the existing ones imo.

random_guy · 23-09-2015 1:27pm

cgcsb wrote: »

but for the cost of an underground turn around would it not be cheaper/the same price to just continue the tunnnel an extra 1km to Docklands as planned.

Absolutely, but someone had asked for an example.
I imagine also the tunnel required for a turnabout like that would be substantial itself. I'm not sure the minimum turning radius these trains could use.

Sam Russell · 23-09-2015 1:38pm

What is the argument for/against a single two way tunnel versus twin bore tunnel?

Looking at the port tunnel, each bore could accommodate a Dart size train in each direction. I would think a single tunnel of larger dimension would be cheaper.

cgcsb · 23-09-2015 2:43pm

a single bore tunnel would be cheaper but would be less flexible in operation and safety would be a more serious concern, e.g. one train derailing hitting another one in the opposite direction would release a substantial amount of kenetic energy. It also complicates maintenance operations and signal repairs, that sort of thing.

You can also achieve better speeds in a twin bore, but I don't imagine speed is a serious issue for urban rail systems with frequent stops

DART+ (DART Expansion)

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