Can Anyone Tell Me Why a Heavy Rail Link to Dublin Airport Can Not be Built in the Short Term?

ArcadiaJunction

I did not want this to clog up the Metro thread.

I know about the capacity constraints. I know about the lack of paths on the northern line. I know there is a Metro planned, but it still seems possible that a new branch from the Northern Line across the green fields and elevated into the airport can be done. It would be relatively painless no?

Even if the services were from the new Docklands station to the airport surely it could cut into some the DART paths while serving stations along the way. Not to replace the Metro, but to eventually integrate with it at the airport? I 100% agree it is not the ideal solution.

Just explain to me why it would be a very bad idea.

goodlad_ourvlad

the chance was lost with the port tunnel not being expanded to fit even single line in, and land for real estate is more profitable with houses on it, than a train line going through it....

There is still the option to go silly amount north and swing back down, but that would go through prime real estate land in and around Swords.

Short answer, board members, councils, land owners, politicians, and developers want money now.... a heavy train line does not make this conducive.

Best we can hope for is some sort of swing off from N3 Parkway or an extension of Luas green.... both are not happening any time soon.

magicbastarder

'heavy rail' and 'built in the short term' don't strike me as mutually compatible phrases.

ArcadiaJunction

https://www.boards.ie/discussion/comment/121095609#Comment_121095609

it is less than two miles of new track!

z80CPU

Politics and the money.

bk

"I know about the capacity constraints. I know about the lack of paths on the northern line. I know there is a Metro planned, but it still seems possible that a new branch from the Northern Line across the green fields and elevated into the airport can be done. It would be relatively painless no?"

According to the All Ireland Rail Review this spur would cost €1 Billion to build.

Why spend that money if the line then carries zero trains?

Because that is what would happen, the Northern line is already at full capacity, so their simply isn't any trains you could run from the city to the airport. Sure, you could run a Howth to Airport shuttle, but the journey time into the city would end up being like twice as long as simply getting Aircoach/Dublin Express into the city, so few would use it.

What makes more sense, is once Metrolink is built, extend it further North and have it interchange into the Northern line then. So passengers from the Northern line would have an easy interchange to the airport.

This makes more sense as it has the dual purpose of opening up massive areas of development land North of Swords where you could house hundreds of thousands of extra people. You can't do this with the proposed DART spur as it is under the airport flight path, so can't build homes there.

KrisW1001

A two-track electrified railway can be built a little faster than a motorway, at a little less cost... It’s just that in this country it’s been a long time since we ever did one from scratch.

The total length of such a spur would be at least 6 km, and would cost around €50~100 million (back of the envelope) to build assuming flat on-surface build with no complications at all. It might be possible to save a little by not electrifying this line, and relying on the Battery-EMU DART trains to service it, but not much in the grand scheme of things.

First problem is where the railway would need to run. A spur due west from the Northern line (branching just north of Portmarnock station) cuts through Kinsealy, Abbeyville and other really expensive places to live. That said, all of Dublin’s other salubrious neighbourhoods are on the DART, so it might actually work in favour of the proposal.

Next problem is getting in to the airport itself. This would require crossing the M1 and old N1, then getting through the outer areas to the terminal buildings. Once in the airport, this could be overground, and an overground line would allow a station serving the Airport Business Park. However, at some point it would need to go down, as Terminal 2 was built with an empty box below it for a rail/metro station, and the ideal from a passenger’s point of view is for all services to leave/arrive at this station.

Third problem: gauge. Metro will go to the airport, but Metro is built on Standard Gauge (1435mm) track. A DART line would be Irish Gauge (1600mm). To use that airport station, a dual-gauge track would be needed to allow both DART and Metro trains to coexist. This kind of setup has never been built in Ireland, but Australian railways have done it in the past. It would be possible to minimise the amount of track required to be twin-gauge, though - just enough to allow Metro and DART to use the same set of platforms. (Metro and DART may differ in electrification: DART is 1500V DC and in future will probably move to 25 kV AC, Metro could be either 750V or 1500V DC depending on how compatible they want to make it with LUAS.. but this is problem that is dealt with by railways across the world).

Journey time would be about 35~40 minutes in a post-DART+ scenario. Without DART+ electrification, it couldn’t be done at all, as there just wouldn’t be space for the extra trains.

None of the problems there are blockers, so, it is possible.

The next question is whether it’s worth the money it would cost. The only intermediate points are Kinsealy, Baskin and the Airport Business Park. Of those, only the Business Park would generate any significant additional traffic on top of the modest demand from the Airport (and it will be modest even before being split between Metro and DART). On that basis, it’s a non-starter. But looking wider, having a DART service to the Airport allows interchange with all of Dublin’s Inter-city rail lines, making it possible to get to Dublin Airport by rail from any other city in the country, which could tip the balance.

But, in the “short term”, I don’t think it’s feasible. It takes us far too long to do any kind of infrastructure in this country. If we decided tomorrow that the link needed to be done, then it would be ten years before a shovel could be put in the ground, and in the two intervening government terms, there’s plenty of time for the project to be canned for political expediency.

bk

"The total length of such a spur would be at least 6 km, and would cost around €50~100 million (back of the envelope) to build assuming flat on-surface build with no complications at all."

The All Island Rail report put the Airport Link cost at €1.1 Billion in 2021 money (so more now). Which in fairness I'd assume includes the costs of an underground station in the airport, etc.

Given that we will already be building an underground station for the Metrolink, it would be much cheaper to just continue Metrolink North of Swords to connect into the Northern Line. It would also have far more benefit in terms of opening up development land in North Dublin.

the_amazing_raisin

Out of curiosity, what would be needed to add more capacity to the Northern line?

There doesn't seem to be that many trains running on it, particularly when compared to other countries where double the frequency of trains seems commonplace

So would revamped and modernised signalling be sufficient?

loyatemu

Irish Rail put in a proposal for a spur some years ago, IIRC it was rejected as it would have undermined the business case for Metro (North, as it was at the time). Also as it would have been only marginally quicker to the CC than existing bus services and provided no extra commuter capacity.

Brian CivilEng

https://www.boards.ie/discussion/comment/121095671#Comment_121095671

How do you make it 2 miles? Every single proposed alignment I've seen puts it at around 7km of double track. The closest the railway track gets to the airport is well over 5km.

SuperBowserWorld

Probably cheaper to move the capital and airport (or switch to Shannon ) to somewhere in the Midlands and run a few rail lines into Dublin for people who can afford to live there and for access to the children's hospital. 😁

Basically the city is blocked to any kind of huge 21st century metropolis kinda city that's going to be needed ... if our climate stays friendly and lots of people have to move here.

bk

"Also as it would have been only marginally quicker to the CC than existing bus services"

This is the big part that really kills this. People either forget or don't seem to realise how close Dublin Airport is to the city. It is less then 10km to O'Connell St. Hell you can cycle it in about 40 minutes.

I know this is unpopular to say here, but the airport is already pretty well connected to the city by the M1 and port tunnel. Just 25 minutes through the port tunnel by the Coach services and not too expensive by taxi. It all makes it hard for expensive rail projects to compete.

Of course we will eventually have Metrolink to the Airport. But I think it is imporant to remember that the main goal of Metrolink isn't to get to the airport, it is to get to Swords and to open up all that development land in North Dublin. The airport is just the cherry on top.

If Metrolink was just a shuttle between the City and the airport, to be honest, I'd be against it and it probably wouldn't get the go ahead on a cost benefit analysis basis, just like the DART Airport spur failed. Metrolink makes sense because it links Swords and all the other tops, in addition to the airport.

Frankly we have far more important things to focus on first fixing with our heavy rail network.

Brian CivilEng

I can 100% state with absolutely certainty that that in no way would be cheaper! 100s of times more expensive. But would be a fun job to work on!

Brian CivilEng

Biggest issue with airport connectivity right now is capacity. I'm regularly having buses pass me by due to being full. Loss of the 90ish capacity 747 and 757 and replacement with the Dublin Express coaches hasn't helped.

bk

"Loss of the 90ish capacity 747 and 757 and replacement with the Dublin Express coaches hasn't helped."

The 747 buses would never have been close to 90 person capacity, not with all the extra luggage racks and people standing with luggage.

Probably around 70 people. A coach is around 55, so there is still some gap in capacity there, but not quiet that wide. However that could be filled by extra coaches or even better overdecker coaches, Overdeckers have 75 seated passengers plus ok luggage capacity. Double decker coaches also an option, but tend to be poor for airport services due to luggage space.

Of course, no one is saying we shouldn't build Metrolink as designed, it is great.

Fred Cryton

We should really have both. Why is it always either or in this country, we've more than enough cash for both. A spur to the Northernn line for people to get to the airport from the DART line and also build the metro to serve Swords, airport.

If we had any vision we would be extending the metro into north Co. Dublin and create 2 or 3 "new towns" with great connectivity to the city. But we don't have any vision unfortunately.

Say what you want about Charlie Haughey but he had the vision to create the IFSC and back the Temple bar area (not a fan of temple bar, but better than derilict buildings). We are sadly lacking policitians with such vision and drive now.

bk

"We should really have both. Why is it always either or in this country, we've more than enough cash for both. A spur to the Northernn line for people to get to the airport from the DART line and also build the metro to serve Swords, airport."

Because while our finances are doing well, we don't have unlimited money! And frankly we have more important heavy rail projects to spend that money on at the moment.

I'm not saying the heavy rail spur will never happen, but it only makes sense after we have quad tracked the Northern line, that needs to come first.

"If we had any vision we would be extending the metro into north Co. Dublin and create 2 or 3 "new towns" with great connectivity to the city. But we don't have any vision unfortunately."

That is almost certainly the next step once Metrolink is completed. I suspect planning for extending Metrolink will begin far before construction finishes, so that we can just roll into it.

KrisW1001

https://www.boards.ie/discussion/comment/121096106#Comment_121096106

I have no idea how they got to 1.1 billion for that link except by perhaps putting most of it in a tunnel. For comparison, Dublin Port Tunnel is 2 x 4.5 km, and cost €750 M in 2006 money. The average figure of €15 M/km for a two-track electrified railway is from the UIC’s European costs database - it was cited in an article that I can’t find right now, so may have been old, but still, it’s hard to see how it could come in at that price. As a short spur with no onward expansion potential, even a single track with a passing loop in the middle would work - it’s only 6-7 km. 1.1 billion sounds like the estimators used MetroLink as a baseline - a project whose cost seems to go up every time it’s mentioned.

(Speaking of tunnelled stations, I believe that as part of the Dublin Airport T2 works there was an empty station box put in place ready for the arrival of Metro... an odd example of forward planning, and also a depressing reminder of how long we’ve waited for a Metro: Dublin Airport Terminal 2 opened in 2009)

The rationale for this is that while the distance from the airport is short to Dublin city centre, Dublin Airport is a national airport, and I would suspect that only a minority of passengers start or finish their journeys in the city itself. An easy link between the national rail network and the major stations would be very useful for reducing car traffic in and out of Dublin Airport (given the cost of parking there long term, many passengers would prefer to go by rail if they could), and for those within the DART’s catchment, a service to the airport would be simpler than having to change modes.

But that would be the ideal scenario. In the real world, I think a fraction of that cost spent on creating a predictable, frequent and reliable bus rapid transport corridor that linked Heuston, Connolly and Dublin Airport would be a better use of the money - as you say, the distance isn’t far; the problem with the current bus is it having to negotiate Dublin traffic, and a segregated busway (one with no taxis!) would fix that issue at a fraction of 1.1 billion euro... I honestly don’t have to be on a train all the way, but I do want to be certain that I’d arrive in time for my flight.

bk

"But that would be the ideal scenario. In the real world, I think a fraction of that cost spent on creating a predictable, frequent and reliable bus rapid transport corridor that linked Heuston, Connolly and Dublin Airport would be a better use of the money - as you say, the distance isn’t far; the problem with the current bus is it having to negotiate Dublin traffic, and a segregated busway (one with no taxis!) would fix that issue at a fraction of 1.1 billion euro... I honestly don’t have to be on a train all the way, but I do want to be certain that I’d arrive in time for my flight."

You could route the red line luas into the port tunnel 😉

The Metrolink will solve most of these problems. Folks coming in from the South East rail line can get on Metrolink at Tara for the airport. Those coming in from the Western lines can get on Metrolink at Cross & Guns. The only missing bit is connecting the Metrolink to the Northern line (other then Tara obviously).

magicbastarder

https://www.boards.ie/discussion/comment/121096686#Comment_121096686

one thing about building a road tunnel - you don't have to budget for the cost of the vehicles using it, or the drivers, etc.

with rail infrastructure, you do.

loyatemu

https://www.boards.ie/discussion/comment/121096302#Comment_121096302

it was actually more recently than I thought that IR were proposing this.

https://www.independent.ie/irish-news/irish-rail-plan-to-link-dublin-airport-with-rest-of-country/30936601.html

Ronald Binge Redux

"In the real world, I think a fraction of that cost spent on creating a predictable, frequent and reliable bus rapid transport corridor that linked Heuston, Connolly and Dublin Airport would be a better use of the money - as you say, the distance isn’t far; the problem with the current bus is it having to negotiate Dublin traffic, and a segregated busway (one with no taxis!) would fix that issue at a fraction of 1.1 billion euro.."

Putting in the infrastructure that would support a tram or even a metro would be a criminal waste of money. Most of the construction cost would be land purchase, and it would be hobbled by its relative lack of capacity.

KrisW1001

https://www.boards.ie/discussion/comment/121096885#Comment_121096885

Yes, and the price they quoted (€300m then, probably €500M now) is much more in line with what I’d have expected. Interesting that they chose a longer run from Clongriffin, but as they said, that land is under the approach/departure flightpath, so can’t be used for housing...

Now that Metro is happening, there’s no chance of this link going ahead too. Personally, I think this would have been a better and cheaper way of serving Swords and the Airport than bringing a metro out so far from the city.

bk

"Personally, I think this would have been a better and cheaper way of serving Swords and the Airport than bringing a metro out so far from the city."

How exactly would it serve Swords!

And 10km is nothing for a Metro line. Hell the Green Line Luas is 24km !

KrisW1001

The IE proposal was to include onward service to Swords, as detailed in the linked article.

It's not the length of Metro, it's the extension outside the city core..it has to go through a lot of empty space (that can't be developed because the Airport prevents it) just to serve the Airport and Swords. Commuter rail is a better solution when you've got stations spaced out like this.

noelfirl

https://www.boards.ie/discussion/comment/121096686#Comment_121096686

It was terminal 1 the train station space was left in - it was requisitioned into the Area 14 check in space some years back.

Podge_irl

https://www.boards.ie/discussion/comment/121098781#Comment_121098781

The "city core" is quite small and it is not a particularly long route for a metro by any global standard. It is also going to be a much, much quicker way into town and will have far more capacity than any linking up with the northern rail line could possible have.

cgcsb

Such a line would not be competitive with buses in terms of frequency, capacity or journey time so it would therefore not be useful, certainly not useful to justify expenditure. And would be made completely redundant by metrolink. It also would not be built quickly. The state has never built a new heavy railway, how could it be done quickly?

If project 4north hoes ahead then such a line may be useful but before then no meaningful capacity is available.

MJohnston

@bk

The only missing bit is connecting the Metrolink to the Northern line (other then Tara obviously).

This is the frustrating one to solve — particularly for Northern Irish passengers on the Enterprise.

You can extend Metrolink to Donabate station, but it makes no sense to stop the Enterprise there.

Makes zero sense to extend the Metrolink to Drogheda where the Enterprise does stop.

NI passengers could swap to Northern line services at Drogheda and then connect to an extended Metrolink at Donabate, but that's a lot of changes. And on the reverse journey, you'd have to time things very well to connect with the right Enterprise service.

My pie-in-the-sky, never going to happen, dream idea would be to branch the Enterprise line from the Northern line somewhere, maybe at Malahide, maybe just after Rush & Lusk station. Then bring it underground from the airport (with a station there) to Connolly.

bk

"You can extend Metrolink to Donabate station, but it makes no sense to stop the Enterprise there."

It would be more likely to extend Metrolink to Rush & Lusk, then Donabate. Keep in mind the goal wouldn't be to just join up with the Northern Line, but to open up development land North of Swords. You could build about four Swords size towns along the line (and parallel to the M1).

It would also have the advantage of allowing for a Metrolink station nearer the center of Lusk (maybe extend to Rush too?), extra capacity if the rail bridge was to collapse again and best of all plenty of space for a proper high quality interchange between Metrolink and Rail at Rush & Lusk station.

I don't see why you wouldn't stop the Enterprise at this station, to allow passengers to change to the Airport (or any other Metrolink station). Sure it isn't a destination at the moment, but it would be with a Metrolink station there.

Strumms

the line would probably have to go underground for part of the journey, also the station, platforms and infrastructure at the airport ? Not sure where it could be built .

KrisW1001

Far more passengers would be arriving via Heuston than any station on the Northern line. With Metrolink serving the city-based population, any mainline airport rail link that doesn’t connect to Heuston will be a waste of money.

Rather than extending the one Metro line further and further away from Dublin, why not build a second line? Networks become more efficient when they interconnect.

Ronald Binge Redux

https://www.boards.ie/discussion/comment/121101125#Comment_121101125

A rare bit of sense among the noise.

bk

“Rather than extending the one Metro line further and further away from Dublin, why not build a second line? Networks become more efficient when they interconnect.”

Because we could house the next 300,000 people in Swords like towns that are actually planned and built at a high density within walking distance of the Metrolink stations.

And all at a relatively tiny cost as it would just be running the Metrolink above ground through what are currently farmers fields. Think of how cheap the Luas extensions have been, it would be similar to that.

And no this isn’t far from Dublin, the area I’m talking about is just 15 to 20km from Dublin. To put that in context, that is closer than Bray and Maynooth at about 25km from Dublin and Drogheda at 50km. I assume you aren’t objecting to DART+ being extended to Drogheda for the same “distance from Dublin” reasons?

Of course ideally we should do both, extend the Metrolink, while planning a second Metro line. The difference is that a Metrolink extension could be done as almost an afterthought, while planning a second underground Metrolink line would take much longer and of course much more expensive. And then of course let’s not forget upgrading the green line to Metro.

The thing is, I can’t see any possible second Metrolink line that would open up the amount of development land as a northern extension would. Never mind the massive cost difference.

I think this is why some of the ideas like bringing intercity to the Airport fall flat on their face. We are in the middle of a housing crisis and we need to do everything we can to help resolve it. Metro/rail projects that allow lots of new homes to be built is the priority. DART+ is great because it opens up the West of Dublin for (more) development and Metrolink does the same for North of Dublin. Projects like brining intercity to the airport do nothing to help resolve the housing crisis, so while a nice to have, fall way down in any priority.

gjim

The problem with extending metro lines is that the PT network density drops with the square of the distance from the center. Fine if the only journeys anyone in these new towns ever need is served by the single metro line but all other journeys will either be car dependent or require new services which means more expense even if the initial extension seemed cheap. Car dependency always remains a factor in commuter towns even where rail PT is available and this will remain the case in Swords to some degree even when the metro arrives. Walking and cycling are no longer commuting options. I’m not even sure what problem we would be solving by planning to house people so far from the centre in new areas which require long commutes to reach the city - it may be marginally more comfortable to spend an hour each day on a shiney new expensive metro than doing the same hour on a steamed up double decker bus from Coolock but it’s still an hour of someone’s life lost every day.

Dublin needs density close to the centre not in new planned towns 25km out. Look at google maps - there’s plenty of brownfield or under utilized land within 10km of O’Connell bridge - it’s only this type of development - relatively concentrated density - that can support dense PT networks.

bk

Seriously people are ok with folks commuting in 50km from Drogheda, but not 15km from planned towns!

“25km out”

The area I’m talking about begins 15km out and ends 20km out, not 25km.

“The problem with extending metro lines is that the PT network density drops with the square of the distance from the center. “

This is why we would build them as planned 15 minute cities. Dense apartment buildings within walking distance of the Metro. Schools, shops, gyms, bars, in the ground floors of the buildings. This is very much inline with international best practices, commuter towns like this a very much a part of cities like Amsterdam and Copenhagen.

Of course I also agree that we need to infill and densify closer to the city too, develop brown field sites like the Dublin Industrial Estate, etc. But keep in mind the population of Dublin is projected to grow by 500,000 people. Infill will only get you so far.

Better to house people in properly planned dense towns, rather then spread across a vast expanse of low density houses across West Dublin.

KrisW1001

@bk I have no objection to DART extensions out that far, but DART is not the same kind of transport as Metro. Once you get away from the city centre, passenger journeys become longer, and so capacity per train and speed of travel become the critical factors. Metro has relatively low capacity per train, and relatively low speed (based on the publicity materials, around 50km/h including stops), but it makes up for it with really high frequency of service (up to 40 tph, peak). That's exactly what you need to serve the centre of a city, but it's not a good fit for connecting a satellite town to the city centre where the distances travelled by most passengers will be long.

bk

Again both Luas lines are already longer then the distance I’m talking about. Metrolink will be much higher capacity and speed than Luas, so it should have no problem handling that area.

Two of the Metro lines in Amsterdam are 20 km, so the same length as I’m proposing.

This is all very much a normal distance for Metro. Also don’t forget, nothing stopping people at say the 20 km end from getting the Metro to Rush & Lusk and change onto the DART+ there if it was faster (not that I think it would be).

Beta Ray Bill

https://www.boards.ie/discussion/comment/121095817#Comment_121095817

Interestingly on this, the latest rail review reports says they want to upgrade to 4 tracks from Connolly to Malahide (I think)

That would increase capacity significantly and allow running trains to the airport.

I genuinely believe I'll be dead or close to dead or old enough that I won't ever be using a plane again by the time the metro is built.

gjim

"Better to house people in properly planned dense towns, rather then spread across a vast expanse of low density houses across West Dublin."

I'm not sure where this is coming from? I've suggested densifying close to the city before building "new towns" 20km (or whatever) from the centre - where did you get that I was advocating covering the countryside in semi-detached housing? The traditional centre (between the canals) is nearly 16km2 and there's over 200km2 within the M50. Dublin already has an enormous footprint relative to its population, I see no social benefits from extending the footprint before exploiting the massive amounts of brownfield, greenfield and underutilised land close to the centre.

The problem with building new towns, disconnected from existing centres is that they are only "cheap" if you forget about all the amenities people need and expect to be able to enjoy daily life. A "15 minute" new town is only any good if there's stuff within 15 minutes. So either you duplicate all the amenities (from hospitals, schools, sports/music/etc. venues, restaurants, shops, parks, etc, etc.) in the new town, at great expense, or you offer poor lifestyle to the new inhabitants.

Investing in dense buildings close to the centre - even if the land costs more - means that the new inhabitants immediately have access to all the amenities of the city. And that any new amenities are of benefit to existing Dublin city dwellers. More can be spent on providing quality public amenities as the spending doesn't have to cover multiple separated "centres".

There's a lot of theory around this subject - historically called the "new towns movement" - and historic experience with this approach in the post war years has been a mix bag - often negative. It typically takes decades before new towns become genuinely liveable and some never do.

MJohnston

@bk

I don't see why you wouldn't stop the Enterprise at this station, to allow passengers to change to the Airport (or any other Metrolink station). Sure it isn't a destination at the moment, but it would be with a Metrolink station there.

Well this is obviously based on optimistic thinking, but if the Belfast to Dublin train was to become High Speed as proposed, I think a stop around here would probably compromise the high speed nature of it.

KrisW1001

https://www.boards.ie/discussion/comment/121103255#Comment_121103255

Your proving my point: in population and area, Amsterdam is a larger city than Dublin.. And yet, its longest metro lines are the same length as the cut down length of one of ours.

Metros are not long-distance transport. The clue is in the name "metropolitan railway".

Luas is a symptom of the same disease.. We have a bad habit of trying to make single projects fix all problems, and overextension of Luas is an example. The western extents of Red Line are so far from Dublin they should really have been served by a new DART service. The Green Line just about gets away with its length because it's mostly on dedicated track which gives it relatively high speed for a tram.

To fix our carbon emissions, we need to densify our cities. To do that in Dublin, we need a high-frequency transport network that lets people get from one part of the city to another, not a collection of non-intersecting lines reaching ever further away from Dublin.

bk

"Your proving my point: in population and area, Amsterdam is a larger city than Dublin.. And yet, its longest metro lines are the same length as the cut down length of one of ours."

Errr.. Hate to break it to you, Dublin has a larger Metro population then Amsterdam!

Dublin Metro Population: 1,270,000

Amsterdam Metro Population: 1,174,000

They also have an extremely close population density. Dublin and Amsterdam are about as close as you can get to two comparable cities.

As a result, the length of Metro lines is very comparable. I'm sorry, but you are dead wrong about this.

"To do that in Dublin, we need a high-frequency transport network that lets people get from one part of the city to another, not a collection of non-intersecting lines reaching ever further away from Dublin."

Which is exactly what Metrolink will do, it will intersect with three of the four heavy rail lines (and could easily be extended to the 4th too). It will also intersect with the two Luas lines. You really don't get much more "intersection" then that and of course it is high will be very high-frequecy, much more then Dart+.

bk

Btw fun facts about Metros here:

https://cms.uitp.org/wp/wp-content/uploads/2020/06/Statistics-Brief-World-metro-figures-2018V3_WEB.pdf

"The average line length globally is 20km and the average distance between stations is 1.25km. There are substantial variations between the longest and shortest line: 82.4km (line 11 Shanghai) and 1.8km (line U55 Berlin) respectively"

So it seems the average length of Metro lines Globally is 20km, so Metrolink should have no problem serving the area North of Swords between 15km and 20km.

loco_scolo

https://www.boards.ie/discussion/comment/121106462#Comment_121106462

What's the argument here? Dublin is extremely comparable to Amsterdam in terms of city area, metro area and greater metropolitan area in terms of population and density.

25minutes commute time from Swords to city centre is extremely good.

KrisW1001

Amsterdam the same size as Dublin? No. Metropolitan Amsterdam is 2.4 million people; Metropolitan Dublin is 1.2 million. The hinterland of Amsterdam (its commutable area) dwarfs Dublin's in population. A 19 km metro line through Amsterdam has an enormous catchment; 19km in Dublin does not. But the Dublin one was supposed to be longer.

My observation is that by stretching out of the city, Metrolink is being shoehorned into a role that metro systems are not well suited to: serving outlying population centres. Talk of extending that single metro line out beyond Swords will just make that wrong choice clearer, and doing so while nothing in the city south west of Stephen's Green has any kind of mass transportation is a colossal wasted opportunity.

I feel that this is being done because, for various reasons, it is prohibitively expensive and slow to build a heavy-rail line in Ireland. Actually, it might be fast and cheap to do it, but nobody knows because effectively no new heavy rail has been built in this country for a century, whereas there is recent experience in building metro-like services (the Green Line is a classic "pre-metro"). I think it's also significant that Metro can be built without involvement from Iarnród Éireann, while DART would require them to be in charge of its construction. Looking from the outside, you'd think TII and IE hate each other...

Why is a metro bad for outlying regions? A metro has high frequency, but the trade-off is lower journey speed and and lower capacity per individual service (like a car's mpg versus top speed figures, that 25 minute service length is not available at the same time as the "with one train per 90 seconds" statistic). Outlying areas of cities tend to follow a tidal pattern: lots of demand for journeys in the mornings, lots out in the evenings, and that requires higher capacity for a very short time period. That's what commuter rail is good at: a long train every five minutes, running at higher speed.

Regarding interconnection, here is exactly where MetroLink will interchange with the existing rail lines. I count two:

From that map it's also pretty clear that Dublin has two huge mass-transport deserts - one in the Northeast, one from Glasnevin around to Coolock, and one from Rialto around to Dundrum. Metro does a very good job of reducing that Northern desert and connecting the North of the city to the centre. I have zero problem with that. It's once it goes north of the M50 that the questions needed to be asked.

loco_scolo

https://www.boards.ie/discussion/comment/121107077#Comment_121107077

The two cities are more similar than you think. Up to county Dublin border, Dublin is denser than Amsterdam with the same population (c. 1.5m). However, outside the county border, the population density falls rapidly for Dublin versus Amsterdam. What's your argument here - that places like Drogheda, Navan, Trim, Naas, Newbridge etc., need heavy rail rather than metro? The map below probably backs that up.

1a) Dublin City is 118sqkm, density 5032/sqkm, population 592k

1b) Amsterdam Municipality is 219sqkm, density 4000/sqkm, population 871k

2a) Dublin Urban is 345sqkm, density 3660/sqkm, population 1.26m

2b) Amsterdam Agglomeration is 448sqkm, density 2500/sqkm, population 1.11m

3a) County Dublin is 922sqkm, density 1580/sqkm, population 1.46m

3b) Amsterdam Urban is 1140sqkm, density 1400/sqkm, population 1.58m

4a) Greater Dublin Area is 2880sqkm, density 593/sqkm, population 1.71m

4b) Amsterdam Metropolitan Area is 2580sqkm, density 980/sqkm, population 2.52m

I used Wiki for most numbers, but used the CSO census website to get guesstimate the GDA. Officially, the GDA excludes Louth but includes all of Meath, Kildare and Wicklow, including all the rural farmland and Dublin/Wicklow mountains. Officially the GDA is 6000sqkm, density 300/sqkm, and population 2.08m.

KrisW1001

"What's your argument here - that places like Drogheda, Navan, Trim, Naas, Newbridge etc., need heavy rail rather than metro? The map below probably backs that up."

Yes, that's exactly the argument. I'd include Swords as a borderline member of that group too, as it's separated from the city by a very low density area (which can't densify due to the airport approaches).

Ironically, it's the presence of the airport along its route that makes Metrolink less effective as a metro here, because the airport enforces a low-population zone around it, and metro works best when the whole length of a line runs through well-populated areas.

Ronald Binge Redux

It's all theory and no practice because shag-all has been built yet. We'll be killing the environment in North County Dublin a little bit more every day for another decade, unless the next Government puts an RPG up the backside of Official Ireland's institutional navel gazing and procrastination.

Podge_irl

https://www.boards.ie/discussion/comment/121107875#Comment_121107875

Why does the airport enforce a low population zone around it?