Project FourNorth (Quad-Tracking the Northern Line)

A study was done in the mid 90's when Irish Rail first proposed an airport link and at the time they found that it was perfectly possible within the city confines.

Effectively it entails a third track to Clontarf Road, which already is there; the current station will have a bay platform on the east side. A reinforced embankment would be provided for the short section from Clontarf Road itself as far as Howth Road and Mount Temple school; this would mean little to no CPO although there would be some disruption while it's being built. From here on the line is in a cutting and it can be widened to Raheny and hence Howth Junction with little engineering bar providing wide road bridges at a few locations.

Once here, the station at Clongriffin is already future proofed; from here it's open country until the approach to Malahide station. A short section of a third line is proposed immediately outside Malahide for use as a turnback slash layover for waiting trains as part of the extended DARTplus project.

Of course the small issue of Exchequer funding and willpower is another story altogether.

4 tracks Connolly to Clongriffin is fairly well agreed as the path forward. Its relatively easy to do. The GNR was looking at this as far back as the 1930's

AISRR was suggesting building the Clongriffin-Airport line and then turning north to follow the M1 alignment towards Drogheda.

4 tracks Connolly to Clongriffin is not relatively easy. The line is in a cutting for much of that stretch with house gardens up to the top of the slopes. There is no space to excavate from or remove excavated material along while keeping the line operational or else CPOing dozens of back gardens.

It'd be 4 tracks to clongriffin and then a new 2 track route from there to Drogheda closer to the M1. There's no need to keep the express tracks by the coast.

If they could work the swords Heavy rail station to be near one of the metro stops, that would provide a handy interchange. Estuary will have a P&R element so could be a good interchange option.

I think it would be pretty difficult to get a heavy rail interchange, even at Estuary station I think there are a lot of space constraints on the line itself, as well as needing to cross the M1 to make the interchange, and then back over at some point which itself isn't easy. If a good connection is important I would almost say it would be better to put the station in Seatown East and run a dedicated shuttle service between The Seatown metro station and this Seatown East heavy rail station.

I don't disagree, but I think it would be difficult to get planning permission for a line that close to Swords without putting a station there.

How would they physically manage that? Without turning around a train, which mean long dwell times, they would have to put the station far enough away that it would probably need an people mover. It's doable but I think it just makes more sense to have a more dedicated airport link and avoid a people mover if possible.

P1 is still used, Connolly terminating Sligo/Maynooth line trains in the mornings in particular. During the day, those trains usually monopolise P7.

Failte Ireland are considering moving… so that site can become a hotel. The petrol station is also owned by hotel developers.

Quad tracking will involve the rebuilding (and possibly moving) of many stations. There may even be one or two closed, where there is no room to quad track on the station (Kilbarrack) Given they won't CPO around connolly, I doubt they'll CPO peoples houses

The biggest problem with Heuston is that it's miles away from the business end of the city. I think diverting trains to that station without a Dart underground is going to just increase journey times.

CPO'ing the land around connolly is a no brainer. (In my opinion anyway) there's no political will to do it though.

I would love to see some more platforms at Connolly! not sure how feasible it is however, and espeically since they are working on the new Spencer Dock station I don't think they have much of a plan to expand which is a shame. However with that said I think the future situation at Connolly is a bit more complicated than just adding a few platforms for terminating west line services. Adding more platforms west of platforms the through platforms would be good for reducing platform congestion and increase capacity for the future (which given why we have Docklands and Spencer Dock it will be needed). But I don't think it's going to make a massive difference with line crossovers, though I also might have a bad understanding of how the current routing into Connolly works. And then it will only get more complicated with the four-tracking.

I would go a bit further than that and say that the long term goal is to turn Connolly into a DART hub. Connolly terminating and GCD through Drogheda and Maynooth/M3 Parkway services. Through GCD HH services (maybe even some terminating services to increase frequency if GCD gets too congested). And through Malahide/Howth-Bray/Greystones DARTs. All frequently interchanging through Connolly. Then like you say, the Hourly Enterprise. However I think its possible that to make room for Connolly DART services Spencer Dock will be used not just for Longford services, but also the Dundalk services(provided its not a GCD services), as well as Maynooth/M3 services as needed. I think they might also used it as the ending point for Sligo services as a stop gap if the Maynooth-Adamstown link is built.

As far as not needing extra platforms, for now once Spencer dock is complete? probably not no, even if they mothball Docklands it would likely be fine for a while (I don't know and can't find what their plan for Docklands is) but its also about thinking about the future in an area that is limited on space.

I never said they shouldn't, I think they should… but I don't think that they will. Political suicide and all that.

Yes - https://www.buildingsofireland.ie/buildings-search/building/50010042/parcels-post-office-102-106-amiens-street-preston-street-dublin-1-dublin . RPS Reference 126.

1-4 Preston Street are also listed.

The front of the KBC building was a notable art deco industrial structure; it was illegally demolished and they had to rebuild it.

Would CPOs there actually make any difference? Someone else can confirm or deny but I suspect capacity is more constrained by the situation south of Connolly than by the number of through platforms in Connolly. If that is the case, relieving that congestion should be more of a priority than adding platforms. I don't see a point in spending a lot of money widening the mouth of the funnel unless something has been first done about the narrow end.

Unfortunately the only real way to relieve that congestion is with DART+ Tunnel. If we ever get around to building the tunnel, I could see the original DU X service configuration being used - Northern Line to Hazelhatch via the tunnel and Maynooth to Bray via Connolly. In that case Connolly would continue to be used as a terminus for Mullingar/Longford services and Enterprise plus more trains from south of Bray. Connolly is well setup as a terminus, it'll continue to have through services but there are limitations on that which aren't related to Connolly itself.

While I don't think adding more through platforms is a great use of space because of the capacity restrictions, using the space to add more platforms for incoming terminating trains from the northern and western lines would still be good for Connolly. Now CPOing the area around Connolly might not be the best way to do more platforms, but in the future Connolly will likely need platforms, as will Spencer Dock (especially if they build the D+ tunnel). Plus extra platforms for northern and western services could still help Rosslare and Wexford services, as if Platform 7 is less congested it could leave room for a few extra services, and that is if building more platforms doesn't include a southern bay platform (to be fair I don't think it would). Though, like you say I do understand that the real limitations isn't Connolly itself. For those services it's the single track past bray with little to no room to improve for a large portion of the track, and that is why there has been talk of diverting Rosslare and Wexford O'Hanrahan services through Waterford.

That said with LC improvements/closures increasing frequency it wouldn't be the worst idea for them to at least consider an extra through platform or two, if not a few southern bay platforms to help with congestion of terminating darts north of Connolly.

A little off topic but now that you mention it, with all the D+ standardisation I do hope they consider having a few Maynooth or HH services extending past GCD. Even if it isn't all the way to Bray, I could at least see a case for a service to Dun Laoghaire and putting platform 3 to some use.

Ah thats a good idea. Im not sure how much use that car park gets but if they moved the sidings into there they could easily get a maybe get a few full length platforms out of it. I will say on the topic of half-length platforms, that could be a good use for the Failte car park. they technically only need to be about 90m and I believe that is enough for HLU commutters and 3-section 22Ks.

The south situation is the same, just needs a 90m platform but I think they would want a 100m platform to at least allow 4-section 22Ks. However while it makes sense with metrolink I don't think they are going to attempt to put another platform into Tara. I think they would more likely either drop a platform into Connolly or GCD, or attempt to rebuild one of the old Pearse platforms. I can't imagine the cost difference between adding a platform at Conolly or Tara would be that different, and I feel like they would rather have it terminate at Connolly like it currently does so it can interchange with ML as well as other rail services, rather than having to shuttle one station over. Realistically though I think reinstating Pearse platforms or adding one at GCD is a bit grim. GCD just looks like it doesn't have the space, and I think the old Pearse paltforms are currently taken up by sidings and stairs.

A third track faces all the same problems as quad-tracking, CPOing required either way.

Not that it would ever happen here, but in the mid 90's we lived near Den-En-Chofu station in Tokyo, over the course of a few years an underground station with 4 platforms was constructed to replace the overground station with only 2. They were then able to construct a shopping center etc on the land freed up. This was done with no interruption to the trains. The station then became a stop where both local and express trains met and changed passengers.

This could be done for Balbriggan, Skerries, Howth Junction and maybe one of the dart stations. Would allow for trains to skip stations, meet with express trains etc

I don’t know who is doing it, but at the end of the day what you keep posting is a supposition on your part.

An article about the debate was posted in another thread but just wanted to drop the debate in here and highlight some key points.

https://www.oireachtas.ie/en/debates/debate/joint_committee_on_transport_and_communications/2024-10-09/

"We will have the work done in the next couple of months. It is well advanced."

“The conflicts which arise from shared train types on a twin-track railway will remain with us until we increase that track capacity. […] We are undertaking a study of the requirements to deliver a four-track section, and believe this critical infrastructure should be accelerated to enable continuing service expansion and significant Enterprise journey time improvement.”

They are using the time table issues to highlight why the four-tracking is needing so hopefully there will be a bit more support for it. Also mentioned was the airport spur, but it does sound like its putting the 2042 in the 2022-2042 transport strategy.

While it definitely isn't an easy decision because there are a lot of branches to consider, I think because of both the amount and frequency of Connolly through services there isn't really an option other than the west tracks being the slow line an the east tracks being fast line. I believe they are doing something similair for Heuston because the layout(more specifically platform 10 / Heuston west), where the north two tracks are the electrified slow lines and the southern two are the fast lines.

It does leave some issues, if a slow service from the northern line is going to Spencer dock or if a Howth service needs to get to the slow line there will be some congestion. However those are at least somewhat fixable with service patterns. For example instead if they need to send some northern line trains to spencer dock because Connolly is too congested or over capacity, they can do that by turning a Drogheda service into an express service on the fast line. The main issue would be if/when they build the M1 express alignment, they they would either have to cross over the slow line or they would need to build an over pass.

Is there any solid information on this?