DART underground - options

The huge weakness in the current DART plans is the absence of any connection between the East/West lines and the North/South line.

If there was such an option, the case for DART Underground would disappear.

There aren't many people who have any desire for the case for DART+ Tunnel, as its now called, to go.

Appalling fag packet/crayon jobs certainly aren't replacements.

And you already can.

Even if there was a second cross-Liffey connection, there would not be direct DARTs - you'd have to change. Your fag-packet bodge would still leave there being no direct connection possible for a train to do that.

Ground is zero metres on that scale.

2.4 meters under ground is, well, underground.

It doesn't stop it being yet another crayon rollercoaster

Laugh away all you want, I'm not the one scrawling crayons of rollercoasters on maps and then resorting to pedantry (and not very well, at that) when unable to challenge anything else.

This is embarrassing at this point. Report after report after report. Nothing happens - excuse after excuse after excuse. Good plans are shelved while annother feasibility/consultancy is launched. Investment which is completely necessary for a growing city with “ambitions” is killed by short term beancounters and nimbyism. Dublin is a bla bla city which can never be a semi-decent European capital and it will kill any advantages it has. Our council, our politicians, our Government should hang their heads in shame.

Apologies if this offends - the late posting is a different time zone rather than a skin full of pints.

If you were able to do the red alignment, would it be possible to branch off around the start of the red line, and tie in anywhere to one of the western rail corridors? Just while the crayons are out.

There's a bigger fundamental question to be answered before the route of a future tunnel can be decided. What does it's main purpose need to be?

• Is it a full Dart Line with services every 3-5 minutes? (High capacity)

• Or will IC and Commuter trains also use the line? (Reduced capacity)

• Things to consider - a 4-tracked Northern Line should be assumed, I think? IC services need stations with multiple platforms, so we can't just jam Cork-Belfast IC trains through a twin track tunnel - direct access to Heuston Main Station and Connolly are needed.

Again apologies for the crayon drawing (as for some reason certain forum members seem to have a real problem with discussing potential designs for this project from a somewhat layperson perspective - something I think is the whole purpose of this forum in the first place…) but would something like this be more feasible…? (In orange)

It feels like the most natural alignment and there is ample space from the Clontarf Road bridge to the east of the current rail alignment to dive two tracks to below the DPT and Tolka before hitting Spencer Dock and curving southwest (to probably GCD instead of Pearse at this stage…) and on to Heuston.

I think if possible and feasible, a Clontarf Road connection would be far more favourable as it takes more services out of the already overcrowded North Stand Jnct, and even if a grade separated tie in isn’t possible, with an eventual 4 tracked northern line, an at-grade tie in to the slow lines will be just the same as anywhere else on the DART network. And with the tie in being after rather than before the station, line crossing can be done while other trains are waiting in the station

Going under the DPT is far less likely to be possible that going over it. Going over it would be less work and less risks involved.

Back to Rollercoaster Tycoon then.

You keep suggesting stuff that involves implausible elevation changes.

1100m at a 2.5% gradient would allow 27.5m drop. At a 3% gradient, a drop of 33m is possible. Electrified railways are more than capable of doing these gradients and higher.

The original DU plans had less distance to fall the same height. Your unconstructive commentary is most unhelpful. Perhaps you could add some actual data or intel to back up your view....