DART+ (DART Expansion)

I see pinch points that might necessitate three tracks in some sections. Which shouldn't be too much of an issue.

I'm not sure I agree with your optimism for a 30 min service to Belfast though.

WILD suggestion here but with the examples above, would it not be better to cut and cover? An additional track both sides and covered with a park/green area so it reduces the noise of the line and looks better? I don't know how much the line is below street level but looks semi-plausible.

On the topic of encroaching development on the railway line. It seems there is no lessons learned in that department. It's currently CIE policy to develop lands adjacent to Connolly and Heuston into residential and commercial use, but somehow it's also policy to more than double the number of trains at these stations by 2040 without adding new platforms or concourse.

Has there been any updates on the 4N feasibility report? Last I heard it was supposed to release sometime in 2025 but obviously that hasn't happened yet. At the very least I would hope it's getting close to publication?

I do agree with a lot of what has been said though, it will be a lot of work, but I doubt there would be anything seriously technically challenging.

If I had to guess the most notable works are going to at Howth Jnc. and Kilbarrack. The former I don't think would be technically challenging, but I think would be the single largest sub-project, as it almost definitely involves a major rebuild of the station. With plenty of space around the station I am hoping it wouldn't be too difficult to expand the station to 6 platforms, but either way platforms 1 and 2 can't survive as they are now. Kilbarrack however does concern me the most as I am not quite sure how they will approach it. No matter what though, a few houses would need to be knocked and even then, I doubt they would propose a 4-platform station, probably something more like the proposed Kylemore Rd Station.

For being a listed structure, I would have liked for it not to be covered in ads. I should have known it was a listed structure, that doesn't surprise me, but imo ads on a listed structure is just shameful.

From an engineering perspective I am not sure how they would solve that other than just building a second visibly identical bridge next to it? Hopefully that won't be a problem.

It won't be possible to excavate and build retaining walls when the only space you have to work on is a steep slope, literally up against a busy rail line with overhead electrical wires and little to no access for long stretches.

This is off-topic for this thread and should be discussed elsewhere but using the Google maps measure tool in this case is the height of naivety.

Not going to get into a big discussion on this as it is off-topic but weekend closures would achieve nothing. You couldn't operate any machinery that close to the operational rail line and live electrical cables. Even with full closure every weekend, it would take a decade. You'd get very little down in a weekend with it so spot/start, and you have to do both sides. That's assuming you can do such heavy engineering works with affecting the power supply, signaling cables, drainage, etc. needed to allow trains to continue operating at all.

Sheetpiling would have to be done from the top given the height of the embankment but there is no flat working space there. To sheetpile from the bottom, you'd need a very big machine and you'd have to remove all cables and supports for it to operate. But in reality, it would be unlikely to be sheetpiled, more likely a permanent contiguous piled wall, which would also be a large machine and would need a level, safe working space at the top of the embankment, which could only come from every garden bordering the rail line.

And that's before you actually start excavating anything, which obviously can't be done from on the slope itself. And all spoil excavated has to be taken away and new materials brought in, so you need access to the public roads, which is a few narrow bridges several metres above the trackbed. So at each bridge you'll need a ramp for trucks to drive up/down.

People here are seriously underestimating the scale of the works required.