Double Track - North Dublin

Zebra3

Can you post a CBA that would would show it is viable?

The Mathematician

https://www.boards.ie/discussion/comment/122020748#Comment_122020748

Yes, most posters seem to be focussing on Belfast, but the main benefit I see would be for places such as Balbriggan and Drogheda. Drogheda is too far out to be properly served by an inner-suburban stopping service. Four tracking would enable the services to be de-coupled into an inner-suburban stopping service to Malahide and Howth, say, and an outer-suburban service to Drogheda and maybe Dundalk, with first stop Malahide. It would also give the option of a pretty fast service from Navan.

bk

https://www.boards.ie/discussion/comment/122020697#Comment_122020697

I'm not inventing anything, I'm reading the All Island Rail Review. You know the report put together by Irish Rail and the other experts in rail! You are the one making things up with a tunnel from Malahide!

To be clear, I didn't say you would need to tunnel from Drogheda! But that the route considered by the AIRR was a new line from Drogheda to Dublin Airport and onto Heuston. They don't go into detail about it, but I'd assume it would be an above ground line from Drogheda to either Swords or the Airport, go underground at the airport, maybe pop up again south of the Airport but go underground again at the outskirts of the city to head to Heuston.

Basically it would replicate Metrolink, running almost parallel with it and cost as much.

Now you said a tunnel from Malahide. But that doesn't really solve the problem as the AIRR says they need to quad track or separate the services all the way to Drogheda, not just Malahide.

I'm not sure what sort of Malahide tunnel you are suggesting, but a Malahide to say Clontarf Road tunnel would be 11km, longer then Metrolink at 9km and the proposed DART+ Tunnel at 7km.

Clongriffin to Clontarf Road might make more sense at 7km, you would need to then combine it with the proposed new line from Clongriffin to Drogheda. You'd be looking at about 7 to 8 billion all in for this.

What the AIRR suggests is the following:

• Quad tracking from Dublin to Clongriffin, 1 Billion
• A new line from Clongriffin to Drogheda basically following the M1, cost 1 billion.

Seriously just go read the AIRR, it is all in there.

bk

https://www.boards.ie/discussion/comment/122021173#Comment_122021173

That is exactly what DART+ North is for. It is the bring DART to Drogheda and to serve the growing population there.

There won't be a separate Drogheda/Balbriggan outer-suburban service, that isn't realistic and these towns really aren't that far from Dublin to require that.

The Mathematician

https://www.boards.ie/discussion/comment/122021448#Comment_122021448

Well yes, they don't 'require it' in the sense that a slow service can be run to them without four tracking, but if we want to provide a game changing service, then it is necessary. Even as things stand, the combined population of Navan and Drogheda on their own is 80,000, and they are at an ideal distance from Dublin for a fast commuter service. They are the sort of towns where we should be building to solve the housing crisis.

bk

https://www.boards.ie/discussion/comment/122021832#Comment_122021832

Unfortunately towns 40km from Dublin aren't the "ideal". Far from it, that would be considered a long distance commute in most countries and not something to be encouraged.

DART+ will be a game changer as it will greatly increase both the frequency and capacity both to Drogheda, but also the various towns much closer to Dublin which are the "ideal" commuting distance from Dublin.

I'm not at all saying we shouldn't quad track, we will need to await the outcome of the upcoming report into quad tracking. I am however saying spending billions on tunnels just to save a few minutes off Dublin to Drogheda or Dublin to Belfast isn't at all realistic.

SharkMX

https://www.boards.ie/discussion/comment/122015753#Comment_122015753

Right after the metro is done :)

The Mathematician

https://www.boards.ie/discussion/comment/122021984#Comment_122021984

I didn't mention anything about tunnels, I was talking about four tracking the line we have.

If it is not an ideal distance for commuting then we should not be doing anything. If we are doing something, then presumably it is because it is considered to be an ideal distance for commuting. Of course we will have to wait until we get the report, but my hunch is that if we compare the cost of four tracking per person in the catchment area of the line past Malahide to the cost per person in the catchment area of the Metro (and I am certainly not saying the Metro should not be built), then it will look to be a bargain.

It is not only about time saved, although that will be far more than a few minutes. At the moment, DARTs take 30 minutes to Malahide, and there is no reason this couldn't be cut to under 15 minutes for a non-stop train. That works out at a saving of over 30 minutes each and every day for all commuters past Malahide. Another important benefit will be the robustness of the service. Four tracks allow for trains to keep running if there is a breakdown, and also allow for easier track maintenance.

Consonata

https://www.boards.ie/discussion/comment/122021984#Comment_122021984

It's probably less about shaving a few minutes off and more about capacity right? Same issue that we're running into with the Rosslare situation, IÉ want to get IC's off the mainline where possible and into termini, by quading like they're doing with Dart+ West, or by terminating services outside the city, like what they want to do with Rosslare services at Greystones/Bray.If we want to get a Hourly or even hypothetically a half horuly Belfast service at peak in the future, that likely isn't going to work if we want to also run an efficient high capacity Dart+ North.

bk

https://www.boards.ie/discussion/comment/122022114#Comment_122022114

Yes, I agree completely. It is more about separating services and maximising capacity of the route. They can probably squeeze an hourly Enterprise through here, this line isn't as constrained as the Wexford line. But yes, long term they need to be separated to reach higher levels of operation like they are doing on the Kildare line.

MJohnston

This is a real laymans drive-by-commenting here but in my experience, the Enterprise is far more often delayed in the North approaching Belfast than it is in the Dublin area.

ArcadiaJunction

<quote>The whole point of this study is to assess the options, and report back on them</quote>

and then politicans and media set about to make sure none of them happen.

gjim

https://www.boards.ie/discussion/comment/122020748#Comment_122020748

You keep repeating this 3 million number but it's just not relevant. What's relevant is numbers in the line's catchment area AND who have a need to get to somewhere else served by the route.

We're not talking about building a service where none currently exists, we're talking about a big spend, a lot of disruption and (most annoying for me) a big diversion of resources away from far more critical issues with PT in Ireland to knock 20 minutes off a service that currently exists and is available to passengers who need it.

There is nothing "ridiculous" about the 3000/day figure - that's the ACTUAL number of average passenger journeys per day on this route according to official rail statistics. I've included a doubling of numbers in my rough CBA earlier even though I don't see where these extra passengers would come from. I could include a quadrupling and it would still look silly in terms of CBA.

There are far more pressing issues for Irish public transport. By a rough calculation, there is about 8 human life years wasted PER DAY just in terms of the difference between commute times in Dublin and the European average for a city of Dublin's size. That's nearly 3000 years of life wasted every year. This is a genuine human tragedy in my opinion. Faster intercity is a future "nice-to-have" compared to doing something to alleviate the misery of the daily commute for 100s of thousands of city dwellers across the country.

Charles Babbage

https://www.boards.ie/discussion/comment/122021448#Comment_122021448

Why shouldn't there be, having PT with 20+ stops means that it is not time effective?

Perhaps there could be express services to Balbriggan, Drogheda and Dundalk or even Newry, but then these would be trapped behind the stop everywhere trains.

loco_scolo

https://www.boards.ie/discussion/comment/122024078#Comment_122024078

By that logic, we should stop investing a penny in every last corner of Ireland and focus solely on Dublin for the next 100years. Utterly ridiculous logic.

I mentioned 3million twice actually. You ignored the comment the first time, then proceeded to produce a rough CBA using the same 3000 daily number you already quoted. You conveniently ignored my point on Heuston Intercity patronage of 24000 per day, which cover a much larger area and distance. Clearly there's enormous untapped potential on the northern corridor.

Just to be clear, I am not suggesting a new intercity tunnel. 4 tracking, or significant sections of 4 track is the best solution, hence why they've allocated funding to access that option.

You keep mentioning 20minutes, but the AIRR suggests Belfast-Dublin journey times of 1hr 10minutes, a 50-60minute saving.

gjim

"By that logic, we should stop investing a penny in every last corner of Ireland and focus solely on Dublin for the next 100years. Utterly ridiculous logic."

It's ridiculous because it's your "logic" not mine.

It's nothing to do with "logic" anyway, it's just standard practice when faced with the common situation where we do not have the resources nor budget to build everything at once. So when presented with a multitude of options which cannot be done all at once, the standard practice is to quantify the costs and benefits of each one.

I ignored the 3 million comment because it's just daft to try to define potential customers based on county boundaries and county populations. There's actually some science to calculating first catchment area and then, with an idea of how many people COULD access the service, you work out how many actually have a need for the service.

I also ignored the Hueston numbers comment again because it's just some arbitrary number you pulled out with absolutely no reasoning on where this 6 fold increase in passengers on the Enterprise would come from.

The AIRR time is predicated on electrification and significant improvements for the entire route NOT for 4 tracking north of Connolly which is what is being discussed. It would require breaking some pretty fundamental physical laws if 4-tracking 15 or 20% of the route could half the journey time.

loco_scolo

https://www.boards.ie/discussion/comment/122032699#Comment_122032699

No one is suggesting doing everything all at once. You've suggested not 4 tracking the Dublin-Belfast axis until everything else is done, which is bonkers. This is a vital piece to connect the 2 largest cities in Ireland, which have historically been poorly connected - socially, culturally and politically. However this is changing very quickly.

You based your logic on current train numbers of 3000 per day which is nonsense. There are 7 daily trains in each direction between Dublin and Belfast. This compares to 21 direct trains daily between Cork, Limerick and Waterford, with additional trains on top of that to Kildare, Portlaoise, Galway etc.

The untapped potential of the northern corridor is enormous and comparing to the southern corridor is extremely relevant.

You just need to look at a population density map to see how much potential there is on this corridor.

cgcsb

https://www.boards.ie/discussion/comment/122015104#Comment_122015104

A 4 tracking project could double the capacity of the coastal DART. There'd be no barrier to running Drogheda to Dublin DART at 5 minute frequency or lower. The 4 tracking also allows the express tracks to move more inland serving the airport with intercity rail and it also offers a much more express commuter service from Drogheda to the city centre. You could forget about Belfast entirely and have Newry to Connolly express commuters taking less than am hour end to end

gjim

https://www.boards.ie/discussion/comment/122033772#Comment_122033772

It wouldn't double it, not unless something like the DART tunnel is built. As it is, DART+ north will provide 9 DARTs per hour peak per direction between Clongriffen and Connolly - about a 6 minute frequency. There would be no way for the system to handle a doubling of this - 18 DARTs an hour (3:20 minute headway) arriving into Connolly?

As it is currently used, the northern line is almost fully dedicated to DART - with the 3 other slots in the DART+N plan shared between commuter and the planned hourly enterprise. The commuter and enterprise services have to crawl between DARTs and match their speed (and all the stopping) - so it's the DARTs that degrade Enterprise and commuter performance, not the other way around.

And because of this, the benefits of 4 tracking would accrue to Enterprise and commuter passengers almost exclusively with at best a couple of extra hourly slots for DART. That's what makes the business case difficult and that is why, every time they've looked at it, they've found something better to do with the money.

Consonata

https://www.boards.ie/discussion/comment/122036552#Comment_122036552

Could certainly effectively double it if they instead terminated Belfast/Dundalk Commuter in Spencer Dock. You don't need Dart Underground to achieve that. Connolly doesn't need to be a bottleneck here.

gjim

Connolly - actually the section south of it could never handle 18 DARTs an hour? It can barely handle half that even with Roslare and Wexford trains turning around at Bray or Greystones.

One issue with the coastal DART route is how the characteristics of the line differs north and south of Connolly - north is free of level crossings and in theory could handle more slots but south is slow and has numerous level crossings which constrain capacity. Similar differences exist between DART SW and W (less capacity, level crossings, etc) which is why a DART tunnel only makes sense to link northern and SW so that neither section is a bottleneck to high capacity through running.

alentejo

PS I am not an expert on these matters but could a third track be added with with relative ease as opposed to a full doubling of tracks. Direction could be swapped depending on time of day!

loco_scolo

https://www.boards.ie/discussion/comment/122036742#Comment_122036742

Just FYI the plans for Dart West at Spencer Dock only have a single alignment connection from the Northern Line to the Spencer Dock platforms. The focus of those plans is connecting to the Drumcondra (GSWR) and Royal Canal (MGWR) lines.

This will seriously limit the potential to terminate some Northern Dart/Intercity/Commuter at Spencer Dock, which I think is a massive missed opportunity.

In any case, it would probably create more conflicts at Connolly than it would solve, as you also have trains from Connolly which head towards Drumcondra.

Bsharp

https://www.boards.ie/discussion/comment/122036995#Comment_122036995

A bi-directional third track was a previous plan that was considered much easier to deliver. Don't know the corridor and its constraints well enough to say whether it's still a plausible idea. I think an airport spur was accessed from the third track as well. It was ended to service intercity with the double track being retained for commuter/dart.

gjim

If a third track could be added cheaply (I don't even buy the 1B estimate for 4-tracking - given the cost of DART+, this feels like an estimate drawn up when DART-U and a north-south metro were estimated to cost "only" 3B), then it would make sense as a single track would surely suffice to support 3 trains an hour each way.

The other option - less sexy than full 4-tracking - is adding passing tracks at selected stations - each time a commuter or enterprise is able to pass a 9/hour DART stopped in a station, it would effectively gain 6 minutes in journey time. You could do the stations one-by-one as part of a continuous improvement program over a period of years avoiding a big-bang 4-tracking project and its associated risks and political hazards. And at the end you'd have most of the benefits which full 4-tracking would have provided.

cgcsb

https://www.boards.ie/discussion/comment/122036552#Comment_122036552

I'm talking North of Malahide where frequencies are proposed to be 10 minutes. That could double if the entrprise ran on new tracks from Dublin to Drogheda, it'd also clear up reliability issues on DART.

The current numbers using enterprise are meaningless in terms of demonstrating demand, it's such a slow crap service that the actual travel demand ends up as cars driving on the M1, and then subsequent demand for adding more lanes to the M1 at hundreds of millions cost. If enterprise had dedicated tracks between Drogheda and Dublin offering a 15 to 20 minute journey between the two at a frequency of 2 or 3 an hour you would see the passenger numbers between Dundalk and Dublin explode. The latent demand is massive.

I wouldn't worry too much about traditional CBA, Ireland's railways have been in managed decline for 100 years we are not at any risk of over-investing in any infrastructure and wont be for a century more if ever.

gjim

As with the Enterprise discussion, there seems to be a reluctance to use basic arithmetic when considering the viability of these proposals.

12 DARTs an hour between Drogheda and Malahide is just completely OTT. Provide the capacity for 24k passengers per hour from Drogheda - a town with a population of just over 40k?

How would anyone justify spending money on something like this, to end up in a situation of having as much capacity between Drogheda and Malahide than between Connolly and Tara - two of the busiest stations in the country in a city centre core of over 1/2 a million people?

The focus needs to be on delivering the most bang-per-buck in rail base infrastructure spending and that means dealing with the mostly poor experience for daily public transport commuters in Dublin, Cork, Limerick, etc. These are the poor saps who spend the biggest fraction of their lives trying to get from A to B. In this example, why should long distance commuters (hardly very sustainable) from Drogheda have a high frequency electrified rail-based metro system while the bus is the only option for a large majority of public transport users in Dublin itself?

The cities with great public transport infrastructure share a pattern - there is more rail and PT density and capacity in the central dense core than there is outside of it which means that once you hit the core, it's quick and easy to get around. Dublin is almost the opposite, the core is starved of high capacity through running services (the loop-line is pretty much it) and has to do with the centre acting as a bus depot while there are tram lines on the outer fringes going through green fields. It's backwards.

Charles Babbage

https://www.boards.ie/discussion/comment/122047384#Comment_122047384

The government must meet the needs of all citizens and not just those living in Dublin. They have blighted the rail network through the country, now you want the one of the main line remaining to be delayed by people going a few Km in Dublin who could just get on a Dublin bus.

cgcsb

https://www.boards.ie/discussion/comment/122047384#Comment_122047384

I don't think anyone is proposing de-prioritising the current Dublin projects though.

bk

https://www.boards.ie/discussion/comment/122047838#Comment_122047838

it isn’t just the current projects, but future ones too. Post 2042 Luas network, a second Metro line, Metro West, DART Underground, etc.

The current Metrolink and DART+ projects are frankly the minimum you would expect a city the size of Dublin to have.

And what of investing in Cork/Limerick/Galways commuter networks? Surely we want to try and at least somewhat balance all the development going into Dublin region.

And what of all the other investments in the intercity rail network, electrification, higher speeds, double tracking, etc.?

I’m not saying it will never happen, but people do need to be realistic about just how much work there is to do across the whole country and how much money and resources are available. CBA’s will need to be carefully looked at decisions made on prioritisation.