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Dublin Metrolink - alternative routes

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  • I was in Dublin last week for a few days and, needing to put in some proper exercise to help with the weight, I decided to walk along a section of what a south-westerly extension of the current metrolink might travel from St. Stephen's Green.

    It has always been my contention that the metrolink between Swords and the city should be extended towards the southwest of the city (some would say the south-central part of the city), eventually reaching places like Firhouse and Knocklyon, primarily because (i) the suburbs along the way generally have higher densities than those along the southside Green LUAS line, (ii) the reduction in journey times along such a corridor would lead to massively reduced journey times, and (iii) no overground LUAS line seems to be readily available in that area.

    There is also no one route on the southside which can act as a counterbalance to the scale of potential passengers provided by Swords, the Airport and Ballymun, and to a lesser extent other northside locations, and I have suggested that Dublin should eventually aim for two southside routes to balance this out: one to/from a Rathmines/Terenure/Rathfarnham/etc corridor and one to/from a Harold's Cross/Kimmage/Walkinstown corridor (this second one mostly does not have anything like the population density of the first, but it has a big prize in terms of public transport integration at Walkinstown Cross).

    Camden Street, just north of the Bleeding Horse pub, where the road is four lanes wide, would seem to present an ideal opportunity for construction of a 3-track metro station, under the road, between St. Stephen's Green and the canal. There really is lots of space there, and the three tracks could initially be used to incorporate a turnback - given the volumes coming from the northside - until a line towards Walkinstown is developed.

    Assuming that the initial stages of the 'Rathfarnham' line are developed first, there seems to be no reason why construction of a line from St. Stephen's Green to Rathmines should cost significantly more than a line between St. Stephen's Green and Charlemont (the current plan).

    The rugby pitch, now apparently an astroturf one, in front of St. Mary's College was in the final stages of being relaid when I walked past. It would obviously be a pity to destroy somebody's new work, but it would be an ideal place to put an initial Rathmines terminus - not costing noticeably more than the current plan to Charlemont. There might need to be be a small amount of CPO of adjacent buildings, but there seems to be scope there either for building a station under the rugby pitch or, an option I would prefer, for building a station under the road and using the pitch as a temporary route for road traffic along Rathmines Road. (There seems to be potential here for removal of spoil - the school has a second pitch there and is adjacent to the Cathal Brugha Barracks, and it surely wouldn't be impossible to figure out some way to get the spoil out by some route involving that, if necessary. The IRFU should be able to step in to find some help with the temporary loss of a pitch).

    Further on on my walk, the petrol station at the bottom of Rathgar Road would seem to be an ideal location for a second station in the Rathmines area. It is, of course, only around 700 metres from the first one mentioned above, but that is a very dense area and it has many buses from other parts. This would not be an unreasonable separation of stations in most cities with a developed metro.

    Beyond that, at the top of Rathgar Road, there's the major junction at the church. This is around 1 km away from Rathmines, so it should obviously be a location for another underground station. Major traffic management required there, but the local population density is decent.

    It obviously gets tougher at Terenure, where there is a major turn required to get towards Rathfarnham, Firhouse and Knocklyon. However, the vehicles envisaged for this metro do have considerable flexibility and an underground station south of Terenure Cross, on Rathfarnham Road, might be an option. This would also be around 1 km from a stop in or around Rathgar Church.

    In the overall scenario which I outlined above for the southside metro lines emerging as a counterbalance to the Swords metro on the northside, this would eventually give a metro line at one end of the Terenure Road West/East catchment on the Rathfarnham/Firhouse/Knocklyon line. With a potential Harold's Cross - Kimmage - KCR-Walkinstown metro line at the other end of Terenure you'd have very effective coverage of an area with very good population density.

    I've often felt that the way to get across the Dodder on the way to Rathfarnham would be to have a standout bridge over the river, perhaps even with a station on it. Apart from being a great advertisement for the metro this would surely be cheaper than going underground across the Dodder, and with the number of roads leading into the bridge it could be the most effective solution for potential passengers.

    I unfortunately didn't have time on my recent Dublin visit to walk further towards Rathfarnham and see how it might eventually pan out. That's for the next time and, in any case Terenure and Rathfarnham are some years away under the current budget.

    Because of pressure of time I had to turn back at Dodder Bridge south of Terenure and walk back along the Dodder, past what I've always called the 'Arc de Triomphe' near Orwell Road and eventually make my way to the Nine Arches and the Milltown stop.

    There'd be a very nice separation of lines into/out of the city if there was a metro line over(or under) the river at Rathfarnham and a line over the Nine Arches. It would be very appropriate for the densities involved.




  • I've been asked to explain this bit: "the reduction in journey times along such a corridor would lead to massively reduced journey times".

    I obviously phrased this badly, but what I meant was that it should reduce journey times significantly at each stage of development of a line to the southwest of the city. Broadly, if there's a metro to Rathmines it would shave 20 or so minutes off your journey; if there's a metro to Rathfarnham it should shave around 40 minutes off your journey; and if there's a metro into town you should be getting to St. Stephen's Green or Tara Street in, give or take, 20-25 minutes or so.




  • You’ve seriously underestimated the size of the metro stations. The ones proposed as part of MetroLink are roughly 100m x 25m plus working width plus construction compounds. None of the locations you’ve “identified” have that space

    1) Camden St.
    4 lanes = 14m... a 3 track station would be 30m x 200m long minimum!
    Where’s the station entrance? The footpaths there aren’t wide enough

    2) St. Mary’s Rathmines
    Now you’re thinking along the right lines, a rugby pitch is around the right size for a metro station box.. shame it’s facing the wrong way.
    Station under the road; where’s the entrance?

    3) Rathgar Road
    The petrol station covers an area roughly 60m long and 30m wide at best. So double the length and maintain the width... not possible

    4) Rathgar church
    Need I say more?

    5) Rathfarnham road
    This appears a very tight radius for a TBM plus the obvious traffic impact plus same issues as Camden St.

    You’re proposing a tunnel portal north of the dodder. Where?

    Now let’s talk population density. How on earth did you come to the conclusion that this route has a higher population than the green line. Did you come across a single building over 5 stories along the route? Did you come across over 100 apartments total? That before you even consider the impact Cherrywood is going to have on the green line (it will sit in the top 30 Irish towns by population!!)

    A Luas serving the portion of the route you’ve proposed via Harold’s cross would have considerably less impact, would be significantly cheaper and would have reasonable journey times.




  • Oh god, how the hell did I end up subscribed to this thread?

    Rapidly clicks unfollow




  • Last Stop wrote: »
    Now let’s talk population density. How on earth did you come to the conclusion that this route has a higher population than the green line. Did you come across a single building over 5 stories along the route? Did you come across over 100 apartments total? That before you even consider the impact Cherrywood is going to have on the green line (it will sit in the top 30 Irish towns by population!!)

    I'm basically just working on the official figures, from the last election.

    Terenure has 4,391 people per sq.km of population, and Dundrum has 3,349 people per sq. km of population.

    Rathfarnham has 4,139 people per sq.km. of population.
    Firhouse has 3,753 people per sq.km. of population.

    These are the official figures which I can currently find. Terenure's population density is obviously much higher than Dundrum's, and heading further out of Dublin you can see that Rathfarnham and Firhouse are also much higher than Sandyford, Glencullen or elsewhere.

    You are writing nonsense.


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  • And, I am sorry, I omitted to comment on the poster LastStop's comment about Cherrywood.

    As I understand it, Cherrywood is not included in Dublin's metro plans.




  • I'm basically just working on the official figures, from the last election.

    Terenure has 4,391 people per sq.km of population, and Dundrum has 3,349 people per sq. km of population.

    Rathfarnham has 4,139 people per sq.km. of population.
    Firhouse has 3,753 people per sq.km. of population.

    These are the official figures which I can currently find. Terenure's population density is obviously much higher than Dundrum's, and heading further out of Dublin you can see that Rathfarnham and Firhouse are also much higher than Sandyford, Glencullen or elsewhere.

    You are writing nonsense.

    Where are you getting those figures? Are you using the Electoral Districts? If so you have to consider that the districts overlap. Half of the Rathfarnham ED would be better served by the green line. The Dundrum Luas serves far more than Dundrum EDs etc.




  • Last Stop wrote: »
    Where are you getting those figures? Are you using the Electoral Districts? If so you have to consider that the districts overlap. Half of the Rathfarnham ED would be better served by the green line. The Dundrum Luas serves far more than Dundrum EDs etc.

    The figures I'm using are the census figures, sorted by electoral district. There are a number of places you can find them, but I use this one:

    https://www.citypopulation.de/php/ireland-dublin.php

    Of course, I said 'figures from the last election' when I meant 'figures from the last census'. Silly me.

    I struggle, as I imagine most readers of the board would, to think of any area of Rathfarnham which would be better served by the Green LUAS than by a metro through Rathfarnham.

    Ballinteer, on the other hand, would be a fine example of a suburb not directly served by either the Green LUAS or a putative metro through Rathfarnham. It has a population of 15,000+ and many of the residents there could be directed towards a Rathfarnham metro station by appropriate bus services. I'd guess many of them are currently using the LUAS so such services would also relieve pressure on the Green line.




  • I have waited for this moment for quite some time now. The unstoppable force meets the immovable object.

    Please, Strassenwolf, Last Stop, continue. I am following with great interest.




  • I'm basically just working on the official figures, from the last election.

    Terenure has 4,391 people per sq.km of population, and Dundrum has 3,349 people per sq. km of population.

    Rathfarnham has 4,139 people per sq.km. of population.
    Firhouse has 3,753 people per sq.km. of population.

    These are the official figures which I can currently find. Terenure's population density is obviously much higher than Dundrum's, and heading further out of Dublin you can see that Rathfarnham and Firhouse are also much higher than Sandyford, Glencullen or elsewhere.

    You are writing nonsense.

    I'm surprised by those figures, I can't understand how the low rise estates of those areas produce higher figures than the higher density apartments along the Luas line.


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  • The figures I'm using are the census figures, sorted by electoral district. There are a number of places you can find them, but I use this one:

    https://www.citypopulation.de/php/ireland-dublin.php

    Of course, I said 'figures from the last election' when I meant 'figures from the last census'. Silly me.

    I struggle, as I imagine most readers of the board would, to think of any area of Rathfarnham which would be better served by the Green LUAS than by a metro through Rathfarnham.

    Ballinteer, on the other hand, would be a fine example of a suburb not directly served by either the Green LUAS or a putative metro through Rathfarnham. It has a population of 15,000+ and many of the residents there could be directed towards a Rathfarnham metro station by appropriate bus services. I'd guess many of them are currently using the LUAS so such services would also relieve pressure on the Green line.

    As I suspected, you’re using EDs which do not accurately reflect the traditional place names we typically use. An example being Rathfarnham attached. As you can see, the east side of the ED is within walking distance of the green line. A Rathfarnham metro station would be miles away from a number of the Ballinteer EDs which border the Luas Line.




  • prunudo wrote: »
    I'm surprised by those figures, I can't understand how the low rise estates of those areas produce higher figures than the higher density apartments along the Luas line.

    Because the EDs do not reflect the typical place names we use. Certain EDs follow the boundary of the Luas line meaning the cumulative density for each stop is significantly higher




  • Last Stop wrote: »
    As I suspected, you’re using EDs which do not accurately reflect the traditional place names we typically use. An example being Rathfarnham attached. As you can see, the east side of the ED is within walking distance of the green line. A Rathfarnham metro station would be miles away from a number of the Ballinteer EDs which border the Luas Line.

    Good work! I never knew that part of 'Rathfarnham' was actually north of the river Dodder. I'd always worked on the basis that crossing the river south of Terenure brought me to Rathfarnham.

    I don't think it changes anything, however. Much of that electoral district would still be within walking distance of a Terenure station on a putative southwest metro line (despite being in 'Rathfarnham'). If I lived right in the middle of that area I'd have a choice: do I go to the LUAS (journey time into St. Stephen's Green ca. 14 minutes) or do I go to the Terenure metro station (journey time to St. Stephen's Green ca. 10 perhaps, if there are stations at Rathgar, 2xRathmines, Camden Street). Not much in it, but I'd probably go for Terenure.

    That one area illustrates very nicely how money spent on a southwest metro could help to reduce pressure on the Green LUAS.

    Farther out, in real Rathfarnham, and Firhouse and Knocklyon, where the LUAS is not an option, the benefit would be in massively reduced journey times into town. Probably to 20-25 minutes to St. Stephen's Green, compared to the 60-90 minutes which it apparently is currently, and each incremental step along the way should provide journey time reductions towards that.

    I'm still not seeing any areas of Ballinteer which border the Green LUAS.




  • Not much in it, but I'd probably go for Terenure.

    (On reflection, if the difference were so small, I think I would probably still go for the LUAS, as it is such a privilege to look at the changing seasons from an overground train).




  • I don't think it changes anything, however.
    It completely undermines the figures you’ve used to “suggest” that the density on this line is higher than along the green line
    That one area illustrates very nicely how money spent on a southwest metro could help to reduce pressure on the Green LUAS.
    The only way to reduce the pressure on the green line, particularly in light of planned development, is to upgrade the green line.
    Farther out, in real Rathfarnham, and Firhouse and Knocklyon, where the LUAS is not an option, the benefit would be in massively reduced journey times into town. Probably to 20-25 minutes to St. Stephen's Green, compared to the 60-90 minutes which it apparently is currently, and each incremental step along the way should provide journey time reductions towards that.
    A Luas is more of an option here! Run it from the dodder bridge along the river with a stop at the shopping centre before going along Butterfield Avenue. You’ve already suggested coming out of the ground north of the dodder so you’ll effectively have a Luas south of here?
    I'm still not seeing any areas of Ballinteer which border the Green LUAS.

    I suggest you review the EDs in more detail




  • (On reflection, if the difference were so small, I think I would probably still go for the LUAS, as it is such a privilege to look at the changing seasons from an overground train).

    So no pressure reduction on the green line? If the green line was upgraded to metro you’d still have this pleasure




  • Not sure about EDs but parts of Ballinteer run down practically to Dundrum shopping center and are very walkable to the green line




  • Last Stop I really want to get back to you about your earlier post re the stations I was suggesting on a putative southwest metro. In particular what I would consider a key station at Camden Street. I'd have said that an underground station would require about 3 metres per track and 3-4 metres per platform (thus 6-8 metres for an island platform), and about half a metre each side for all the wiring, etc. Thus a 3-track station with an island platform should require a total footprint of around 22 metres maximum.

    A friend of mine who is involved in building and has one of those laser measuring devices has promised to measure the relevant bits of my local station over the next couple of days, and when he reports back I'll have a clearer idea. (My local station has four tracks and two island platforms - one for long distance trains and one for local trains). I'll get back to you as soon as I can on that.
    Last Stop wrote: »
    It completely undermines the figures you’ve used to “suggest” that the density on this line is higher than along the green line

    I can't see how it does.

    It is difficult in the Rathmines electoral area, which has very high density and includes Rahmines, Rathgar and Ranelagh, to differentiate between potential passengers who might use the currently available Green LUAS and those who might use a putative metro through Rathmines and Rathgar. All I can say here is that it would not be unusual for a developed city to have at least two rapid rail lines serving such a high density area along two or more corridors.

    Moving further out, you have (for example) the Terenure electoral areas (population: 17462; population density: 4,391 per square kilometre), the Rathfarnham electoral areas (population 22,161; population density 4,139 per square kilometre)*, and the Firhouse electoral area (population:23,949; population density: 3753 per square kilometre).

    These are all very respectable population densities.

    *This includes the 'Rathfarnham' bit which you pointed out above has parts which are close to a LUAS line.

    In contrast - and I'll have to go back to the figures again to analyse other areas - the Dundrum electoral areas have a total population of 23,653 and a population density of just 3,349 people per square kilometre. The Clonskeagh areas neighbouring the LUAS have a population density of a paltry 2,789 people per square kilometre.
    Last Stop wrote: »
    The only way to reduce the pressure on the green line, particularly in light of planned development, is to upgrade the green line.

    Not so. Developed cities reduce the pressure on any one line by having competition between lines. Dresden, whose public transport system includes many tram lines, has always been a favourite of mine and illustrates this very nicely.

    In any case, the authorities have decided that there is no need to proceed with an 'upgrade' of the southside Green LUAS for at least a couple of decades.

    (I still can't get why people talk about replacement of the Green LUAS with a metro as an upgrade. It won't get people into town any quicker and will actually lengthen a very considerable number of journeys on the route).




  • Last Stop I really want to get back to you about your earlier post re the stations I was suggesting on a putative southwest metro. In particular what I would consider a key station at Camden Street. I'd have said that an underground station would require about 3 metres per track and 3-4 metres per platform (thus 6-8 metres for an island platform), and about half a metre each side for all the wiring, etc. Thus a 3-track station with an island platform should require a total footprint of around 22 metres maximum.
    1) that’s still roughly 8m wider than the current 4 lanes
    2) your “calcs” do not allow for the width of the station walls which could be 1m wide.
    3) your “calcs” do not allow for construction space. To drive the station wall, you’ll need at least 3m at the very minimum
    4) a 3 track station requires considerable extra length to get from the tunnel width to 3 track station width. This would push the station through the junction at either end causing traffic chaos
    A friend of mine who is involved in building and has one of those laser measuring devices has promised to measure the relevant bits of my local station over the next couple of days, and when he reports back I'll have a clearer idea. (My local station has four tracks and two island platforms - one for long distance trains and one for local trains). I'll get back to you as soon as I can on that.

    Again internal dimensions

    I can't see how it does.

    It is difficult in the Rathmines electoral area, which has very high density and includes Rahmines, Rathgar and Ranelagh, to differentiate between potential passengers who might use the currently available Green LUAS and those who might use a putative metro through Rathmines and Rathgar. All I can say here is that it would not be unusual for a developed city to have at least two rapid rail lines serving such a high density area along two or more corridors.

    Rathmines is far from high density
    Moving further out, you have (for example) the Terenure electoral areas (population: 17462; population density: 4,391 per square kilometre), the Rathfarnham electoral areas (population 22,161; population density 4,139 per square kilometre)*, and the Firhouse electoral area (population:23,949; population density: 3753 per square kilometre).

    These are all very respectable population densities.

    *This includes the 'Rathfarnham' bit which you pointed out above has parts which are close to a LUAS line.

    In contrast - and I'll have to go back to the figures again to analyse other areas - the Dundrum electoral areas have a total population of 23,653 and a population density of just 3,349 people per square kilometre. The Clonskeagh areas neighbouring the LUAS have a population density of a paltry 2,789 people per square kilometre.

    When you compare the population density of areas on both sides of the green line, they are significantly higher than the ones you have quoted and growing!!
    In any case, the authorities have decided that there is no need to proceed with an 'upgrade' of the southside Green LUAS for at least a couple of decades.

    (I still can't get why people talk about replacement of the Green LUAS with a metro as an upgrade. It won't get people into town any quicker and will actually lengthen a very considerable number of journeys on the route).

    Please explain how it is a replacement and not an upgrade?
    Are they replacing the tracks - no
    Are they removing stations - no

    It will be considerably quicker between Charlemont and O’Connell!!
    Which journeys will take longer?




  • It's even better than I'd hoped for.......


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  • I'm going to have to leave your stuff about "calcs" as I don't know what you are talking about.
    Last Stop wrote: »
    Rathmines is far from high density

    Rathmines is very high density, in a Dublin context. I can't think, off the top of my head, of a suburb in Dublin which has a higher density.
    Last Stop wrote: »
    When you compare the population density of areas on both sides of the green line, they are significantly higher than the ones you have quoted and growing!!

    You may be right, perhaps with up-to-date local knowledge, that it is growing on both sides of the line. I only have the 2016 census figures to work with.
    Last Stop wrote: »
    Please explain how it is a replacement and not an upgrade?
    Are they replacing the tracks - no
    Are they removing stations - no

    It will be considerably quicker between Charlemont and O’Connell!!
    Which journeys will take longer?[/QUOTE]

    No, they're not replacing the tracks. And, no, they're not removing any stations. They are sensibly carrying on, as is.




  • I'm going to have to leave your stuff about "calcs" as I don't know what you are talking about.

    Think that might be better rephrased as you don’t know what you’re talking about based on your station box calculations (shortened to calcs)
    Rathmines is very high density, in a Dublin context. I can't think, off the top of my head, of a suburb in Dublin which has a higher density.

    Ballymun, Beaumont, Cabra all have higher densities
    In any event the most dense part of the Rathmines ED is around Ranelagh who would benefit fit far more from the green line upgrade
    You may be right, perhaps with up-to-date local knowledge, that it is growing on both sides of the line. I only have the 2016 census figures to work with.

    That’s even using 2016 stats
    No, they're not replacing the tracks. And, no, they're not removing any stations. They are sensibly carrying on, as is.

    If you could answer the question asked in future rather than trying to be smart to avoid admitting misinformation that would be great




  • Last Stop wrote: »
    Think that might be better rephrased as you don’t know what you’re talking about based on your station box calculations (shortened to calcs)

    I've told you, up above, that I'm waiting for a definitive answer about the size of a 4-track station size in a city with a well-developed public transport system. We can then work out, perhaps by extrapolation:D, what the dimensions of a of a 3-track station might be.
    Last Stop wrote: »
    Ballymun, Beaumont, Cabra all have higher densities
    In any event the most dense part of the Rathmines ED is around Ranelagh who would benefit fit far more from the green line upgrade

    Ballymun, Beaumont and Cabra may indeed have higher densities (I haven't yet looked). But they're not being discussed as locations for alternative routes. Ballymun is on the route of the proposed metro, but I've yet to see any proposed alternative metro route through Beaumont or Cabra.

    You say that the densest part of the Rathmines electoral district is Ranelagh. Can you show that to us?
    Last Stop wrote: »
    That’s even using 2016 stats

    Yes, unfortunately all I have to hand is the census data for 2016
    Last Stop wrote: »
    If you could answer the question asked in future rather than trying to be smart to avoid admitting misinformation that would be great

    I wasn't trying to be smart. The NTA themselves said they are not going to replace the Green LUAS line on the southside for around two decades, or more, because it isn't necessary.

    I think that Dublin should use those two decades to deliver quality, and rapid, public transport to other southside areas.




  • I've told you, up above, that I'm waiting for a definitive answer about the size of a 4-track station size in a city with a well-developed public transport system. We can then work out, perhaps by extrapolation:D, what the dimensions of a of a 3-track station might be.

    Ah great I look forward to the internal dimensions
    Ballymun, Beaumont and Cabra may indeed have higher densities (I haven't yet looked). But they're not being discussed as locations for alternative routes. Ballymun is on the route of the proposed metro, but I've yet to see any proposed alternative metro route through Beaumont or Cabra.

    This was in direct response to your statement that you can’t think of any suburb with a higher density than Rathmines. I’ve just given you 3 examples
    You say that the densest part of the Rathmines electoral district is Ranelagh. Can you show that to us?

    “Rathmines A” ED has the highest population density of the Rathmines EDs and covers Ranelagh.
    Yes, unfortunately all I have to hand is the census data for 2016

    Even using that data, the green line catchment has a higher density


    I wasn't trying to be smart. The NTA themselves said they are not going to replace the Green LUAS line on the southside for around two decades, or more, because it isn't necessary.

    I think that Dublin should use those two decades to deliver quality, and rapid, public transport to other southside areas.

    The question I asked was what makes you say the green line would be replaced by metro as opposed to upgraded?
    The green line upgrade is necessary, unfortunately the NTA weren’t willing to upset the NIMBYs




  • I would have a Metro going out to Tallaght, whether that is the one going via Walkinstown or the Knocklyon one (maybe both).

    Eventually, it would be great if the original Metro West could swing around from Tallaght and on to Knocklyon and through to Dundrum (maybe in time Bray).

    Aside from the quality of life argument, there is the positive environmental impact of a top quality four or five metro line system in the city. It will pay for itself in the years to come.

    Places like Knocklyon have a big population with alot of young people. Rathmines is a very busy area ideal for a metro. Terenure/Rathgar covers a big area and a well positioned station could be very well used. Rathfarnham has a big population and a lot of people who are desparate for top level public transport. Tallaght deserves more than a Luas. It is a city with a huge population.

    I remember once meeting a retired engineer on holiday who was involved on the original M50. He argued for three lanes with a metro like train running overhead on the route at the time. He was laughed out of it and was told Dublin would never need more than two lanes of a motorway and a metro type train was pie in the sky stuff. At least back in the 80s and early 90s, there was an argument that the country was much poorer than now.

    The lesson from his story is to always plan for the future.




  • I've told you, up above, that I'm waiting for a definitive answer about the size of a 4-track station size in a city with a well-developed public transport system. We can then work out, perhaps by extrapolation:D, what the dimensions of a of a 3-track station might be.


    Any update on this?




  • Last Stop wrote: »
    Any update on this?

    Indeed there is. I just got the figures from my friend with the laser late this afternoon.

    My local station has two island platforms, one for mainline services and one for commuter trains. (There are no underground trains in my city).

    One platform (the intercity platform) has a width of 9.70 metres and the other (the commuter platform) has a width of 9.10 metres, each with a set of steps leading to/from the platform near the end (but not actually at the end - there are lifts at each end, on both platforms, and enough room either side of the stairs for access to/from those lifts).

    The two tracks between the platforms have a total width of 8.28 metres, which accomodates both commuter and intercity trains, and occasional freight trains. In other words, the operational requirement for safe throughput of trains, in my town, is 4.14 metres on each track.

    Obviously, the space required by trains on the outside tracks should be the same, perhaps lower as they don't ever have any obstacles like oncoming trains in their path, but certainly not higher.

    Thus we can safely say that the total operational width required by my local station is 35.36 metres (thirty-five point three-six metres).

    If we now transfer those figures from an overground station in continental Europe to a possible 3-track underground station in or around Camden Street in Dublin with an island platform and a side platform, and assign a width of 10 metres per island platform, 5 metres for the side platform, 4 metres per track, and let's say a total of 1 metre either side for the cabling and the concrete box, you come up with a side-to-side operational footprint of 29 metres.

    You might be able to reduce the platform size a bit by having those glass doors that some metro systems have - I'm not sure if they are planned for Dublin's metro - and the figures above may also be a little skewed by the fact that my local commuter train is operating in an environment which also includes freight trains and intercity trains - as mentioned above - though they are not on the same tracks. Dublin's metro would not be.

    Even so, I can't see how the overall operational footprint of a potential 3-track Camden Street station could be got down to below about 27 metres (twenty-seven metres).

    I think to build a junction station serving Rathmines, etc., on one branch of the proposed metro and Harold's Cross and Walkinstown on another, as I have suggested, you would probably have to compulsorily purchase (and demolish) the one-level Zaytoon, Boylesports and other buildings on that stretch of Camden Street near the Bleeding Horse. If that were done, such a station at Camden Street should be eminently feasible. Other solutions are doubtless possible.

    (Of course, it may be that building a station under what are one-storey buildings, effectively a stretch of bungalows near to the city centre, while leaving them intact, is actually an option).

    I am a little hampered because I'm not aware of any website which allows preliminary assessment of the urban space in Ireland, street widths, etc. Other countries that I work in seem to have variously more or less developed versions of something like this.

    I am also curious about this post:
    Last Stop wrote:
    Camden St.
    4 lanes = 14m... a 3 track station would be 30m x 200m long minimum!
    Where’s the station entrance? The footpaths there aren’t wide enough

    Why 200 metres?

    If you can build the operational 'station', with the tracks and the platforms, you can then build the mezzanine level with shops and ticket machines and pastry sellers and so on, and the whole thing becomes progressively bigger or smaller as needs be at street level.

    I still struggle to see how a metro station for a 90 metre tram could morph into a station with a length of 200 metres.

    (There is of course a precedent, in that the exalted people at An Bord Pleanala even approved, under the earlier metronorth plans, a station at O'Connell Bridge which was around 400 metres long for a tram which was just 90-metres).

    I'm curious why you think that a length of 200 metres should be necessary for a metro station in a location like Camden Street.




  • You can make a metro station pretty much any width you want. Just stack the platforms. There is no law that says the tracks have to run side-by-side.




  • So an internal station width of 27m is proposed for your station at Camden St. So 29m external plus 3m construction space either side is 35m wide.
    You’ve now moved the station from that short stretch at the bleeding horse to the opposite side of Charlotte way which carries more traffic. While it may have been possible to close the short stretch of road outside the Bleeding Horse during construction of the box, the closure of Camden St would impact all the buses serving Rathmines and Rathfarnham.
    You’re now also taking about a significant amount of CPO which would drive up the price making it more expensive than Metrolink in this area.

    The reason you need a 200m long station is to accommodate the 3rd platform. The tunnel only accommodate the 2 tracks so to create the space required to move from 2 to 3 tracks plus the space for an island platform you need to lengthen the box


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  • You can make a metro station pretty much any width you want. Just stack the platforms. There is no law that says the tracks have to run side-by-side.

    This would require the tracks in the tunnel to be stacked. This option was looked at as part of the tunnel configuration study for Metrolink and Dart underground but they chose single bore side by side for Metrolink so if you’re tying into that at Stephens Green you need the same tunnel configuration.


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