DART-Airport Spur From Clongriffin

Jayuu

lxflyer wrote: »

People do seem to be ignoring the fact that Howth will benefit with an increased service (albeit a shuttle between Howth Junction and Howth during off-peak) of 4 trains an hour every hour rather than the current hotch-potch. The only losers really would be Malahide/Portmarnock, which would lose the DART in off-peak, but if there was a half-hourly diesel that ought to be sufficient.

But the point here is that we'd be spending €200 million to create a service that would help one group of people at the expense of another.

It's complete short-term thinking and at some point in the future when the economy recovers, which it will, we'd probably end up building Metro North anyway and rendering the spur obsolete.

dowlingm

I don't think a spur would make Metro North redundant. After all, they largely serve different catchments. The DART line would be more convenient for passengers from Dundalk/Drogheda/Skerries/Balbriggan/Howth/Bray to change trains at Howth Junction for the spur. Metro North does little/nothing for them like the spur does nothing for Ballymun/DCU/north inner city.

Metro North's mistake in my view was that they did not extend the original design to the Northern Line. Offering the ability for Drogheda/Dundalk/Balbriggan/Skerries people to transfer at Malahide, Donabate or Rush would have brought in more political capital than the mere park and ride in the middle of nowhere at the north end of the line. Instead the debate revolved around City Centre-Airport trips.

And now - it's likely there's no money for either line

Niles

With hindsight (a wonderful thing I know), one wonders would it have been better never to have electrified Howth Junction-Malahide, left it as a reasonably frequent diesel service, and instead constructed this Airport branch. Ah well.

Seriously though, if the Airport DART branch goes ahead, perhaps consideration could be given at some point to serving the non-Airport MN line with a Luas route. That way the Airport gains its supposedly essential rail link, the communities that would have been served by MN get a light rail service, and it avoids the need for a seperate Metro system with its own dedicated, standalone, trains and depot, etc...

AngryLips

Setting aside MN for a minute, why has a spur from Maynooth/Dunboyne line been passed over for a spur on the northern line?

L1011

AngryLips wrote: »

Setting aside MN for a minute, why has a spur from Maynooth/Dunboyne line been passed over for a spur on the northern line?

Distance (more), development in the way and suffering the exact same problems with lack of slots due to the line joining the Northern Line.

Niles

AngryLips wrote: »

Setting aside MN for a minute, why has a spur from Maynooth/Dunboyne line been passed over for a spur on the northern line?

Less available land maybe? And if you went from the Dunboyne branch itself it would quite circuitous. Though it would help towards the capacity issue.

LXFlyer

Jayuu wrote: »

But the point here is that we'd be spending €200 million to create a service that would help one group of people at the expense of another.

It's complete short-term thinking and at some point in the future when the economy recovers, which it will, we'd probably end up building Metro North anyway and rendering the spur obsolete.

You are and you aren't.

You are removing the off-peak direct service on the Howth branch and replacing it with a more frequent shuttle.

Malahide and Portmarnock would lose (on average) one off-peak DART an hour - would that necessarily be such a big loss?

Peak time would still have direct services from Malahide and Howth, presumably with the shuttle continuing also connecting into the airport DARTs.

cgcsb

Niles wrote: »

Seriously though, if the Airport DART branch goes ahead, perhaps consideration could be given at some point to serving the non-Airport MN line with a Luas route. That way the Airport gains its supposedly essential rail link, the communities that would have been served by MN get a light rail service, and it avoids the need for a seperate Metro system with its own dedicated, standalone, trains and depot, etc...

Niles, metro and luas are the same thing. the metro has slightly wider trams that could not be suitable for the red line luas.

cgcsb

lxflyer wrote: »

You are and you aren't.

You are removing the off-peak direct service on the Howth branch and replacing it with a more frequent shuttle.

Malahide and Portmarnock would lose (on average) one off-peak DART an hour - would that necessarily be such a big loss?

Peak time would still have direct services from Malahide and Howth, presumably with the shuttle continuing also connecting into the airport DARTs.

the thing is, it's making a sh*t service even sh*ter to accommodate another sh*t service. When there is a simple 4 step solution to the city's transport needs:

-DART underground,
-Metro North,
-Integrated ticketing
-More bikes

a DART spur is just a ridiculous attempt to pacify the plebs. We have no money and we will continue to have no money as long as we continue to give our money to former millionaires who are too posh for the dole.

I'm happy to wait a few years in order to have Dublin's transport needs fulfilled. adding more band aids to the patchwork is just PR.

Niles

cgcsb wrote: »

Niles, metro and luas are the same thing. the metro has slightly wider trams that could not be suitable for the red line luas.

Different vehicles though. Even from something as simple as a spare parts aspect it's more economical to keep as little diversity in the fleet as possible. (In fact, I've seen this cited as a reason behind way the infamous Alstom DARTs have lain unused for nearly half a decade). The Metro cars would be different to the Luas vehicles, for example. The past has seen Luas vehicles transfer, on occasion, between the Green and Red lines. With Metro North this won't be possible, and unless Metro West was ever built (not anytime soon) it would continue to use its own equipment, own pool of parts, etc...

Of course, this isn't a reason in itself why Metro North shouldn't be built, but it is one which adds to the argument suggesting that a northern Luas line might make more economic sense.

cgcsb

Niles wrote: »

Different vehicles though. Even from something as simple as a spare parts aspect it's more economical to keep as little diversity in the fleet as possible. (In fact, I've seen this cited as a reason behind way the infamous Alstom DARTs have lain unused for nearly half a decade). The Metro cars would be different to the Luas vehicles, for example. The past has seen Luas vehicles transfer, on occasion, between the Green and Red lines. With Metro North this won't be possible, and unless Metro West was ever built (not anytime soon) it would continue to use its own equipment, own pool of parts, etc...

Any luas tram can operate on metro north and any metro tram can operate on luas green

Niles wrote: »

Of course, this isn't a reason in itself why Metro North shouldn't be built, but it is one which adds to the argument suggesting that a northern Luas line might make more economic sense.

again metro north and "a northern luas line" are the same thing. The only different is branding. Metro North is likely to be re-branded as luas anyway.

AngryLips

cgcsb wrote: »

Any luas tram can operate on metro north and any metro tram can operate on luas green

I'm not sure if this can be done without some changes to existing infrastructure. Given that metro rolling stock is wider I would expect that metro rolling stock could not operate on Luas Green line unless the platform width was reduced away from the tracks to allow the wider metro trains. Conversely, any Luas operating on metro spec lines will have a larger gap between the tram door and the platform than is currently the case. Both are interchangable to a degree but it remains to be seen if it would allow flexibility of rolling stock that you imply.

cgcsb

AngryLips wrote: »

I'm not sure if this can be done without some changes to existing infrastructure. Given that metro rolling stock is wider I would expect that metro rolling stock could not operate on Luas Green line unless the platform width was reduced away from the tracks to allow the wider metro trains. Conversely, any Luas operating on metro spec lines will have a larger gap between the tram door and the platform than is currently the case. Both are interchangable to a degree but it remains to be seen if it would allow flexibility of rolling stock that you imply.

the green line was designed to accommodate wider trams for a future up grade to metro. there is a gap on most dart services between the platform and carriage, doesn't seem to be a problem

Brian CivilEng

As far as I am aware no decision has yet been made on the exact vehicles to operate on the metro north line, that will be up to the winning consortium that builds it. The RPA will however give specs for the vehicles and they will be inter-operable with the luas, although it is unlikely that will be used in operation.

The metro trams wont be wider than Luas. That misconception from the distance between the tracks on the green line which was supposed "future proofed" to be updated to Metro in the future. The reason is due to the swept path of the Metro at high speeds, which requires a greater distance between the lines. Two metro cars passing each other on a bend on the red line would collide, whereas this wont happen on the Green line.

Luas and Metro are basically the same thing, Metro just being built to a higher standard. It's kind of like the difference between a bus lane and a QBC.

Niles

Fair enough. I still think it would make more sense to keep everything as standard when it comes to new non-IÉ systems. I guess it's all hypothetical at this stage anyway!

Ernest

"..it's kind of like the difference between a bus lane and a QBC."


There IS such a difference?????

Brian CivilEng

Ernest wrote: »

"..it's kind of like the difference between a bus lane and a QBC."

Yes of course there is. A bus lane is just a lick of paint down the side of the road, restricting one of the lanes to public transport wherever there is room. Westland Row for example. Bus lanes on their own are useful to get buses down a particularly congested street, although right turning movements and normal junctions mean that their benefits are limited.

A QBC looks at the whole corridor, the bus lane is there for all or a significant portion of the main bus route. The QBC doesn't just aid existing scheduled services, services can be scheduled to get the most out of it. The route is designed to be as straight as possible, the signals and junctions are designed to give the bus priority over other traffic. The Stillorgan QBC is the best example in Dublin, primarily because the room was there along the N11 to build it.

dowlingm

LUAS trams are, IIRC, 2.4m wide. The swept path on Red line assumes only 2.4m vehicles or narrower. LUAS Green was built for 2.6m wide at a future date I believe from the point of view of vehicles passing each other but I think the platforms would have to be shaved back 100mm should 2.6m wide vehicles enter service. Not sure about Sandyford yard whether similar future proofing was done.

Ernest

So a "QBC" is just a hyped-up bus lane, then. QED

27061986a

are there any maps showing a detailed route of the proposed dart line? I would love to see one.

dubhthach

27061986a wrote: »

are there any maps showing a detailed route of the proposed dart line? I would love to see one.

Not that I know of, at the moment it's pure "pie in the sky" stuff. Here's a bog standard one I created in mspaint. Obviously I avoid any major areas of devolpment (around clongriffen station and the graveyards)

27061986a

THANKS DUBHTHACH FOR THE MAP. IS THE PROPOSED DART LINE GOING TO RUN TO SWORDS OR IS IT GOING TO TERMINATE AT DUBLIN AIRPORT. IF SO IT SEEMS POINTLESS BUILDING IT IF ITS GOING TO SERVE ONE STOP ONLY. A PARK AND RIDE AT THE M1 INTERCHANGE MIGHT BE OF SOME BENEFIT.

dubhthach

27061986a wrote: »

THANKS DUBHTHACH FOR THE MAP. IS THE PROPOSED DART LINE GOING TO RUN TO SWORDS OR IS IT GOING TO TERMINATE AT DUBLIN AIRPORT. IF SO IT SEEMS POINTLESS BUILDING IT IF ITS GOING TO SERVE ONE STOP ONLY. A PARK AND RIDE AT THE M1 INTERCHANGE MIGHT BE OF SOME BENEFIT.

I'm assuming you are typing in Caps by accident (not very nice otherwise), anyways the idea floated in press has no connection to Swords at all. Just a line from Airport to Clongriffen. I also think it's laughable that they claim it can be provided for €200m

Brian CivilEng

Ernest wrote: »

So a "QBC" is just a hyped-up bus lane, then. QED

No not "QED", it's QBC

A bus lane is a part of a QBC. All bus lanes are not QBCs but all QBCs contain bus lanes.

Speaking of bus lanes, there used be one along the N32, the aim of which was to connect the Airport to the DART station. That bus route failed, the bus lane is still marked on the road but hasn't been operation in years. Funny that a route where there was a complete lack of demand on the bus is now being considered for upgrade to DART.

Ernest

"Speaking of bus lanes, there used be one along the N32, the aim of which was to connect the Airport to the DART station. That bus route failed, the bus lane is still marked on the road but hasn't been operation in years. Funny that a route where there was a complete lack of demand on the bus is now being considered for upgrade to DART"


See my earlier post on 28th July on this thread about the now defunct N32 Bus Lane.

It just goes to prove that clumsy bus lanes (or even Fantasy Bus Corridors, if you prefer) are no substitute for properly integrated rail links.

Brian CivilEng

Ernest wrote: »

See my earlier post on 28th July on this thread about the now defunct N32 Bus Lane.

It just goes to prove that clumsy bus lanes (or even Fantasy Bus Corridors, if you prefer) are no substitute for properly integrated rail links.

Sorry, I missed that when I read through the thread.

strassenwo!f

There seem to be at least two issues here which need consideration. (Probably more)

The first is the spur from Clongriffin, which seems to run through fairly low density territory. This means that, unlike the metro north, this is only a project to facilitate connection of the city with the airport.

The second is the apparent necessity to four-track the northern line out to the entry/exit point for the spur.

Has the option of building a tunnel been from Killester or Harmonstown been properly considered? I haven't looked at it closely, but it looks like it would take a tunnel of a couple of km to get from Killester/Harmonstown to the area currently being considered for the spur. This tunnel could serve areas like Coolock and Darndale on its way to the airport. These are quite high density areas which were not planned to be directly served by the metro north project, or any known LUAS project.

It would seem that the easy part of four-tracking is the section out to Killester, then it gets harder, especially beyond Harmonstown. Most of what would be required could be nibbled from Mount Temple school and Clontarf Golf Club. The four-tracking costs for this section would be relatively small, compared to the costs for four-tracking in the more northern section. So the saved money could be put towards reducing the costs of the tunnel section.

And a tunnel and (mostly) overground route from Killester/Harmonstown might also approach the airport in such a way as to make it easier to extend to Swords in the future.

Such a project would undoubtedly be more costly than four-tracking the northern line, but surely a lot cheaper than the metro north project. And it would serve areas not really served by the metro north, so that it need not become redundant when the money is around for (most of) metro north to eventually be built.

It would also fit in nicely with the signalling upgrade on the loop line.

Ernest

Perhaps I misunderstood earlier postings but I did not think that four-tracking the DART between Connolly and Howth Junction was part of the plan. I understood that improved signalling alone would enable the higher density of train service to be made possible. I also understand that pigs can be made fly once they have better avionics circuitry installed....

BluntGuy

I read somewhere that some kind of scoping study or feasibility study or what have you will be done on 4-tracking the northern route. Maybe it was in the 2030 Vision document. But beyond that, nothing.

dowlingm

Tunnelling under an active line would be tricky, I'd say... not to mention ruinously expensive. Some three tracking would make a big difference but also sorting out the 2-track bottleneck between Fairview and Connolly.

I wonder if the spur could also handle a small storage yard immediately beside the Northern Line to relieve Fairview and reduce morning deadheading? Suddenly the spur would be useful for more than just airport runs.