N8/N25/N40 - Dunkettle Interchange [open to traffic]

This is what we all thought, and presumed, but the gantries (although they are crap) are saying different at the moment. The width of the approach being built from the N25E to the tunnel seems to be two lane throughout by eyeballing Dronehawks videos, which is leading me to start to think we'll end up with two lanes from N25E to tunnel, and that traffic coming from the M8 Dublin will have to merge into the right hand lane going into the tunnel. And given the shockingly poor merging lane lengths on this scheme so far (M8N and M8S to N25E), I don't think it'll be a very good solution.

I don't like that idea, I much prefer one lane from the N25E and one from the M8 flowing neatly into the tunnel. But I've yet to be convinced that thats what they're doing.

Amazing video from Dronehawk - just shows the scale of the project.

I may have said this previously when looking at one of these videos but I think it's worth saying again. Given the number of interchanges, links, diverges, roundabouts that all have to be delivered with a very constrained area and with a train line running through it this really is an incredible piece of engineering and planning. I'm sure there have been compromises that have had to be made given the nature of it all but when this is open it's going to be an remarkable piece of infrastructure and a real boon to the city.

Big month starting tomorrow.

I'm really getting sick of queuing in the evenings for the tunnel by Smyths toys on the Kinsale flyover.

Opening of the filter lane to town and removal of traffic lights from Tivoli to DKI should help with the ridiculous northbound traffic situation in the evenings.

There are two lanes going on the new part of the slip to N25E, so I would hazard a guess that both lanes of the tunnel will actually go N25E, with slips to the left and right for Tivoli and Dublin respectively.

Hopefully the signage will be updated and not remain shocking.

You can't judge the final flows based on current traffic: right now, heading North and East from the tunnel is less restricted than heading West towards the City. When the Tunnel-City slip opens, that bottleneck will clear, and the flows will even out.

... deleted, been posted already.

Eastbound carriageway was lined on the night of May 30th

May 30th

June 1st

That would be excellent if that were the case! Perhaps he knows someone on the project. Or maybe he just emailed them and asked!

Todays newsletter -

• We hope to progress a temporary tie-in between Link M/Structure ST04 and the N25 Westbound on the weekend of Friday the 23rd of June 2023 - see layout plan above and photograph below.
• The works required will necessitate the closure of the N25 Westbound diverge to the Dunkettle Interchange Roundabout. It is proposed to close this diverge between 8pm and 9pm on Friday, the 23rd June 2023 with the diverge reopening as quickly as possible but not later than 12 noon on Sunday the 25th June 2023.
• The main diversion route will be via the R623 through Little Island and it will also be possible to access the Jack Lynch Tunnel via a U-turn at the Tivoli Roundabout.

The works are being carried out under weekend/night-time working in order to minimise disruption to traffic but additional time should be allowed for journeys in the area during peak times on Saturday the 24th June 2023.

Interesting one this - they are going to do a tie in from the new Little Island south roundabout towards Tivoli, and presumably open the new roads to facilitate N25W to tunnel traffic.

Not quite what I predicted, but it means that a lot of traffic can be taken off the roundabout. And a lot of circulating traffic too. I'd have to think about it more, but it means the crossing movements (M8S to Tivoli mostly, and Little Island to N25W) can be taken off the roundabout. In theory, I THINK that means that the big one, tunnel to N25E can be made freeflow as, with the opening of the loop from Tivoli to tunnel and a few diversions, there is no need for traffic lights there anymore.

We wont mention that that weekend will be utter pandemonium, but it'll be worth it.

I’m not sure I fully understand what I’d happening. Are they saying that they are opening a temporary link to go from the dumbbell south roundabout onto the n25 westbound towards Tivoli.

Won’t this require an at grade junction with the N25 to roundabout diverge if the original diverge reopens?

Isn’t it much more likely that part of the new alignment will open to remove the need to fan at grade junction as ST04 will be used?

That sounds like the obvious scenario. Interested to see how fast they can get a temporary link done. I think the following quote was just poorly written in the newsletter:

“with the diverge reopening as quickly as possible but not later than 12 noon on Sunday the 25th June 2023”

They’ll need to build a small embankment over the current N25 to roundabout slip.

This one change will be transformative. Having no lights at the exit if the tunnel is the one biggest reason for this project.

In case you’re not aware, the DKI project team has been at pains to point out in the last couple of newsletters that the closure you’re referring to and the resurfacing that necessitated it are unrelated to the DKI project. Different contractor.

Bad for years, especially the exit from the roundabout going towards Midleton. Shocking.