Dublin Metrolink (just Metrolink posts here -see post #1 )

Sam Russell

CreativeSen wrote: »

Im confused, apologies. Is the metro conversion of the green line not "Metro South" and is that not a different (as yet unplanned and unbudgeted) proposal to Metro North. So why would they need to stall Metro North for that?

The conversion of the Luas Green Line to Metro was designed in from the start. It only needs a few km extra to get to Renalagh which is probably as easy as to do a turn around underground.

jd

Sam Russell wrote: »

If they could get away with a single bore like the port tunnel, it is less tunnelling than the port tunnel (18km).

Each bore in the port tunnel is 4.5 km, for a total of 9km, unless I'm missing something?

Idbatterim

Lads a quick question. Given that the cost saving measures are all pretty much bull****, shorter platforms? lol. Less rolling stock? Had rolling stock been ordered for metro north? Lol. The running it at grade in ballymun, that will be fought again. The only other cost cutting measure they made was dropping one underground station. Could they not just seek a revision to the original scheme for that? Without having to go through this entire farce again? I appreciate grandeeod that i am being perhaps somewhat naieve in giving them even the slightest benefit of the doubt that they ever want this thing built...

GerardKeating

CreativeSen wrote: »

Im confused, apologies. Is the metro conversion of the green line not "Metro South" and is that not a different (as yet unplanned and unbudgeted) proposal to Metro North. So why would they need to stall Metro North for that?

In the original "Platform for Change" Metro South was the continuation of Metro North to Tallaght, via Kimmage, Harold Cross etc.

not1but4

GerardKeating wrote: »

In the original "Platform for Change" Metro South was the continuation of Metro North to Tallaght, via Kimmage, Harold Cross etc.

Found this map while trying to find that alignment which I think others might find useful.

Future Dublin Transport - Platform For Change (2015-2025)
https://www.google.com/maps/d/viewer?mid=14x7vqF_4_3SFpfg_L2Q1hvRYbOc&hl=en&usp=sharing

Peregrine

CreativeSen wrote: »

Im confused, apologies. Is the metro conversion of the green line not "Metro South" and is that not a different (as yet unplanned and unbudgeted) proposal to Metro North. So why would they need to stall Metro North for that?

The current plans seem to be for the Metro North to surface south of Stephen's Green and go onto the current Luas Green Line somewhere between Charlemont and Ranelagh upgraded to the same standard (easy job) to form one big metro line from the Southside to the Airport, Swords and beyond. It would allow TII to double the frequency on that segment of the Luas Green Line and double the length of trams from the current 43m. It shouldn't be that much more expensive than Metro North stopping at Stephen's Green and turning around in an underground loop, it unleashes a lot of unused potential of the original Green Line and it makes the project more politically viable.

Idbatterim

did abp rule that it should be run underground through ballymun or did they simply have underground running from the get go in this area after public consultation and knowing it would be appealed?

cormac616

How will the cross city operate whenever metro south is implemented? Will it just be a shuttle between broombridge and charlemount? Surely they can't have those larger metro trams going through college green!

jd

Idbatterim wrote: »

did abp rule that it should be run underground through ballymun or did they simply have underground running from the get go in this area after public consultation and knowing it would be appealed?

AFAIR, the original proposal was to have an elevated railway up the middle of the Ballymun Road. There were loads of objections (overlooked homes etc) during the consultation, so the plan was amended to have it underground until around Santry Cross, at an increased cost.

The plan for Optimised/New Metro North is overground but on street level..

jd

cormac616 wrote: »

How will the cross city operate whenever metro south is implemented? Will it just be a shuttle between broombridge and charlemount? Surely they can't have those larger metro trams going through college green!

Cross City would probably terminate st Stephens Green. The larger metro trams would continue underground through city center and on to airport/Swords (Metro North route)

Ernest

Is this another way to go?

http://www.dailymail.co.uk/news/peoplesdaily/article-4565992/China-unveils-track-train-runs-virtual-rails.html

Featured in the Daily Mail today (but widely circulated elsewhere over the internet) is this battery-operated train/tram developed in China with rubber wheels running on an embedded virtual track and said to cost a fraction of heavy-rail metro and presumably equally heavy-rail trams like Luas but without the cost of digging up the street to align and lay embedded metal rails and overhead electric cables.

The attached newspaper report describes the vehicle as driver-less but photos included and other linked video material on the internet shows a driver holding a steering wheel in the front carriage, though this may only be in testing track use. Linked video shows also the train raising up two charge arms to top up the battery but its not clear how often this needs to be done or whether this can be done while train/tram is stopped to let passengers on and off.

Anyway, what do the various experts on this forum think?

yer man!

This is basically a bus, a lot more could be achieved for lower cost with a segregated bus lane and using bendy buses.

xper

The planning application for the Nationwide House site has been updated with revised plans agreed between the developer, the National Transport Authority and Transport for Ireland that addresses the concerns of the latter two agencies regarding the stability of the existing Luas embankment (the original Harcourt St Line structure) and providing for the proposed alignment of Metro South.

I've superimposed one of the new drawings on to Google Maps to give us a sneak peek at this key part of Metro South's route:



So the red lines indicate pilings that will be placed at basement level 2 on either side of what may be a metro tunnel approaching the current green line alignment. If you extend the red lines north, this is consistent with a station being located at st Stephen's Green East (acknowledging that tunnels can take sharp turns!).

What is perhaps surprising is that the proposed building has a basement level 1 (mostly car parking) that extends over the pilings at basement level 2. So if this was the tunnel alignment, it would very much be a tunnel at this point, not the portal, and the line would be c.15 meters below the current Luas tracks level. If the track were to start rising immediately after the building footprint, it would have an incredibly steep ramp to reach the green line on its direct routing or it would have bend eastwards and run alongside it for some distance.

Alternative explanations:

• The portal isn't in this location at all but much further south and the proximity of the Metro to the green line here is to provide an interchange between an underground station and the Charlemont stop but this sounds like an expensive design which would seem to negate the point of dumping the Metro North plan for New Metro North.
  
• They may even be sending the northbound metro tunnel onto the west side of the green line to provide a grade separated junction, facilitating dual running of Luas and Metro services south of the junction.
  
• The pilings are not for the metro tunnel itself but are for an access structure to an underground station. The note on the drawing itself refers to "works to facilitate possible Metro / Luas interchange".

Bray Head

If you follow the lines due south you could conceivably have a tunnel portal where Dartmouth road is - it's the one that runs east-west under the existing Luas line.

This could possibly be achieved by CPO-ing 30 and 32 Dartmouth Road and the gardens of Camridge Terrace, which runs perpendicular to it.

One issue is that 30 and 32 Dartmouth Road are on DCC's list of protected structures.......

wakka12

Bray Head wrote: »

If you follow the lines due south you could conceivably have a tunnel portal where Dartmouth road is - it's the one that runs east-west under the existing Luas line.

This could possibly be achieved by CPO-ing 30 and 32 Dartmouth Road and the gardens of Camridge Terrace, which runs perpendicular to it.

One issue is that 30 and 32 Dartmouth Road are on DCC's list of protected structures.......

Dartmouth square is a really well preserved old square it'd be sad to lose buildings in it.

Winters

It is a real pity that the RPA/TII didn’t acquire "Three Park Place" before Clancourt group developed it. http://www.threeparkplace.com/location/

That plot of land from Hatch Street to Adelaide Road would have been much more suitable and cost effective for a track transition from underground to street level at Adelaide Road and then to link to the high-capacity compatible remainder of the Green Line to Sandyford. Commercial development could then have proceeded above the ramp and the TBM portal could have been located in Iveagh Gardens or St Stephen's Green.

The alternative of tunnelling 3km south to somewhere in the region of Alexandra College grounds in Milltown or further south seems ridiculous especially considering the line becomes light rail again south of Sandyford.

Just a few notes regarding "green line conversion to metro". The majority of changes proposed are: increase in tram frequency i.e. headway/trams per hour and also increase in tram capacity via new rolling stock (length/width and seating config). Street running i.e. at-grade pedestrian and vehicle crossings as well as track speed restrictions (curves and gradients) are where frequency and tram length become restricted.

ricimaki

Its interesting that the drawing shows bored tunnel to the north, and cut-and-cover tunnel to the south. The shape of the west piled wall also shows that something is planned towards the north of this site, presumably the interchange station mentioned above.

I wonder if they are planning the terminate the green line Luas at Charlemont station, and disconnect it from the southern metro line altogether. The tunnel portal would be along the existing LUAS route between Northbrook road and the Ranelagh stop. There would be a short cut-and-cover section (roughly 150m long) between the Nationwide House site and Northbrook road. The tunnel can rise 5M between at this section, and then then the last ~10M before Ranelagh stop.

There would be a lot of disruption during the construction of this, but it would be a good setup when complete. An interchange station at Charlemont would connect it up to the Luas line, and a station at St. Stephens Green east would work well for Dart Underground (in the unlikely chance it gets built).

Sam Russell

ricimaki wrote: »

I wonder if they are planning the terminate the green line Luas at Charlemont station, and disconnect it from the southern metro line altogether. The tunnel portal would be along the existing LUAS route between Northbrook road and the Ranelagh stop. There would be a short cut-and-cover section (roughly 150m long) between the Nationwide House site and Northbrook road. The tunnel can rise 5M between at this section, and then then the last ~10M before Ranelagh stop.

It would appear from earlier documents that the section from Brides Glen to Bray is planned as Luas but Metro north of that. If that is so, the depot at Sandyford would retain a Luas function, and Luas trams would transit (with or without passengers to Bray from there. If so, it could also supply trams north to SSG and onto Broombridge. Of course the number of trams required for the BG to Bray would be few.

I'm not sure what is actually planned, if anything. The routing shown was quite tortuous, so Metro might not be suitable or even possible.

Grandeeod

Winters wrote: »

It is a real pity that the RPA/TII didn’t acquire "Three Park Place" before Clancourt group developed it. http://www.threeparkplace.com/location/

That plot of land from Hatch Street to Adelaide Road would have been much more suitable and cost effective for a track transition from underground to street level at Adelaide Road and then to link to the high-capacity compatible remainder of the Green Line to Sandyford. Commercial development could then have proceeded above the ramp and the TBM portal could have been located in Iveagh Gardens or St Stephen's Green.

The alternative of tunnelling 3km south to somewhere in the region of Alexandra College grounds in Milltown or further south seems ridiculous especially considering the line becomes light rail again south of Sandyford.

Just a few notes regarding "green line conversion to metro". The majority of changes proposed are: increase in tram frequency i.e. headway/trams per hour and also increase in tram capacity via new rolling stock (length/width and seating config). Street running i.e. at-grade pedestrian and vehicle crossings as well as track speed restrictions (curves and gradients) are where frequency and tram length become restricted.

The real issue with converting the Green line to metro goes back to the 1990s and the infamous political argument about on street running through the city centre or underground. Anyone old enough will remember the incoming FF lead Government of 1997 completely changing luas plans and embarking on new studies to check the feasibility for putting it underground. Mary O'Rourke was the MOT tasked with running the show. A year earlier Bertie Ahern is on record in a Dail debate (while in opposition) as being completely opposed to on street running along Harcourt Street etc.

In the end we got the two unconnected luas lines with some sort of "plan" to eventually upgrade the Green line to Metro. The only engineering feature applied to the Green line in relation to a Metro conversion was the distance between the running lines as it was anticipated that Metro vehicles would be wider. To my knowledge there was absolutely no thought given to where or how a conversion/connection to an initially underground Metro South would happen. I consider it to be a sloppy fudge to get the original luas project into construction.

lateconnection

If the drawings say "works to facilitate possible luas/metro interchange" then there will be a station.

Yes, of course additional costs will be incurred by doing this, however it is an idea that makes an awful lot of sense.

A HUGE amount of people get off the Luas at Charlemont during the morning peak and get back on during the evening.

Here is the proof: https://m.youtube.com/watch?v=B4btYpKVlWw

The inside of the Luas very notably clears out after Charlemont in the morning. They use the footpath alongside the canal and walk towards Leeson Street Bridge and I would even say onwards towards Baggot Street.

Very few people cut through Harcourt Terrace or head toward Portobello from Charlemont Luas stop. I would say about 80 percent of people that use Charlemont head towards the Lesson Street Bridge direction by walking alongside the canal.

If the next metro stop after Ranelagh was SSG East, these people would face a longer walk to their workplace, which might discourage them from using the Luas.

The NTA may have recognised these high numbers and see the merit of building a metro station underground there.

xper

lateconnection wrote: »

If the drawings say "works to facilitate possible luas/metro interchange" then there will be a station.

Yes, of course additional costs will be incurred by doing this, however it is an idea that makes an awful lot of sense.

An interchange station between Metro South and a truncated Luas green line of course makes perfect sense. The surprise, to me, is that the metro stop would be underground. I would have thought it possible to come above ground at this site and provide platforms integrated into the portal or immediately south of it but, while a lot of detail is still unknown, these drawings seem to indicate that that particular scenario doesn't appear to be the plan.

The biggest unknown is whether the intended outcome is to have the Luas line completely disconnected from Metro South, have a rare-used engineering-only link (like the red-green line connections), an out-of-service-only link to allow trams daily access to the Sandyford depot or a full passenger services link, possibly grade separated. Whatever they have decided is the requirement will go a long way to dictating the location and nature of the tie-in.

not1but4

Grandeeod wrote: »

The real issue with converting the Green line to metro goes back to the 1990s and the infamous political argument about on street running through the city centre or underground. Anyone old enough will remember the incoming FF lead Government of 1997 completely changing luas plans and embarking on new studies to check the feasibility for putting it underground. Mary O'Rourke was the MOT tasked with running the show. A year earlier Bertie Ahern is on record in a Dail debate (while in opposition) as being completely opposed to on street running along Harcourt Street etc.

Is there anywhere I can find out more details on the original route for the Luas? I've only been able to information on Wikipedia https://en.wikipedia.org/wiki/Luas#History

Sam Russell

Mod: I've moved posts on bendy buses to a new thread as it is off topic here.



https://www.boards.ie/vbulletin/showthread.php?p=105713261#post105713261

Winters

I suspect that post "metro conversation" that beyond the high capacity section of the green line alignment there will just be shorter rolling stock running to Bray or wherever and at a decreased headway. Thus you may have a service still running from south of Sandyford to the city centre but it wouldnt not be as frequent or carry as many passengers.

They are probably looking at running the peak hour 'Metro' services from Swords to Sandyford. It'll be something similar to the how the DART can scale up with train lengths and not every train going to Greystones.

not1but4 wrote: »

Is there anywhere I can find out more details on the original route for the Luas? I've only been able to information on Wikipedia https://en.wikipedia.org/wiki/Luas#History

The original route of Tallaght to Dundrum hasnt changed much since circa 1997. There were route options down Emmet Road through Inchicore village but the Grand Canal route was preferred. I did my thesis on the planning back in 2001 so im sure I have some old route option maps at home.

Edit: Found them, PM me and ill send them on.

not1but4

Two people recently told me that because of geological features of Dublin the costs of constructing an underground system are very high in comparison with other cities of similar size and complexity.

Does anyone know if there is any truth behind this?

I've found some mention to it on a reddit thread so not sure how correct these people are.

I read something about tunneling being hard in Ireland due to the high water table or something like that. Certainly we have very few tunnels in Ireland, so have little expertise in the area.

I'm a geologist and part of my PhD involved gathering depth to bedrock information for Dublin.

The geology of Dublin makes building an underground metro quite difficult. Dublin is underlain by karstified Kalp limestone, the depth to bedrock is highly variable; with pinnacles of bedrock separated by channels of deep boulder clay and ancient fluvial overburden. For example, between O'Connell Street and Trinity College, you can find bedrock within a few meters of the surface next to deep overburden 80 meters deep just 10s of meters apart.

The fluvial (river) deposits near the Liffey are particularly problematic. These deep river deposits were formed by the Paleo-Liffey at the end of the last Ice Age when sea levels were ~100 meters lower than today, the Liffey eroded a deep valley that was infilled by stones, sand and mud. The channel runs parallel but usually slightly north of the modern Liffey.

Up until 20 to 30 years ago, it was impossible to drill a tunnel through such difficult conditions, where a tunnel would drill through solid rock and then suddenly encounter unconsolidated sediment.

Contrast this with London, were Victorian and Edwardian engineers were easily able to dig tunnels through the London Clay. This clay is impervious, this reduced problems of water flooding the tunnels. Also, the clay so soft it could be literally dug out by shovel. However, even in London, the Underground was hampered in by the underlying geology. The London Clay is a lot thinner south of the Thames, that is why most of the London underground lines are on the north side of the Thames.

Zebra3

There is an underground motorway in Dublin so I can’t imagine there being a geological problem building an underground rail system.

MJohnston

Zebra3 wrote: »

There is an underground motorway in Dublin so I can’t imagine there being a geological problem building an underground rail system.

The Port Tunnel doesn't exactly have a comparable location and route

lucernarian

In the grand scheme of things, I find it astonishing that CPOs and the likes are considered around Ranelagh, when the plan with existing planning permission would perfectly serve the needs of communities and the city (kinda why hundreds of people worked on and got this huge project approved)

Why is it so important to have the existing green line served with a more streamlined and ~ 30% higher capacity service? (54 metres to a whopping 60 metre train, plus frequency increases allowed)

The line from charlemont to SSG isn't a problem, it's practically a blessing for those who live and work near it. It's stupid to compromise on platform lengths and then take the crayons out on the green line.

D.L.R.

lucernarian wrote: »

Why is it so important to have the existing green line served with a more streamlined and ~ 30% higher capacity service?

Question answers itself. And 30% sounds conservative.

wakka12

not1but4 wrote: »

Two people recently told me that because of geological features of Dublin the costs of constructing an underground system are very high in comparison with other cities of similar size and complexity.

Does anyone know if there is any truth behind this?

I've found some mention to it on a reddit thread so not sure how correct these people are.

Well he certainly sounds like he's knows his stuff anyway