N8/N25/N40 - Dunkettle Interchange [under construction]

Chris_5339762

It's a great example of how to do it. People are interested in big works like this, so knowing what is going on is fascinating - especially on a project of this complexity.

They had the drone out quick-smart too, two hours from flyover open to video posted.

Hibernicis

https://www.boards.ie/discussion/comment/118546848#Comment_118546848

North facing camera giving a great view of the movement across the new bridge. It looks as though the traffic lights controlling the flow from the M8(S) onto the roundabout have a more generous time slice than the old ones.

https://www.dunkettletraffic.ie/live/?id=3

Corkladddd!!

Crossed the new bridge today, a very nice job however there is a decent drop to get down to the new lights that I think could take a few people by surprise as they get used to the new layout. Freshly laid tarmac, rain and exuberance could see this being a bad spot for tips for a period of time as people adjust...I hope common sense will prevail for a lot or people but I think some presence from AGS for a few days could be helpful, not necessarily prosecuting (unless justified) but insuring that people slow down and take due care...

Also anyone coming down the M8S will need to stop at the white line and not over it like people normally do as it will tie the junction in knots for those of us trying to get to N24 from tunnel!

Chris_5339762

In theory its all a 60kmh zone so people wouldn't ever be in a position where they couldn't stop of course.

In reality when I am literally the only car going 60kmh with buses, lorries and every other car passing me, god knows how it will go!!!

AugustusMinimus

https://www.boards.ie/discussion/comment/118555889#Comment_118555889

IMO, they need to add dashed lines into the roundabout to guide cars into the correct lanes on the roundabout itself.

Everyone was fine When I went through it earlier. However, it only takes one person to veer off course and potentially cause a crash.

hans aus dtschl

https://www.boards.ie/discussion/comment/118553993#Comment_118553993

Yeah that old swivel bridge was attempted to be blown up by the (I think Carrigtwohill company of the) IRA during the war of independence. But even before the railway, there was a direct route there, Dunkettle Bridge, and the swing bridge (Swivel Bridge) came in with the addition of the railway and Dunkettle Station (1845).

The alignment from Tivoli through Glanmire village would not have been the direct route to Midleton. I'd say it never was, to be honest, the route instead would have been the "Old Youghal Road" which goes through St Lukes, Dillon's Cross, Tinker's Cross, New Inn, Church Hill, Glanmire Bridge, and instead of the L2998 it cuts Eastwards towards Caherlag and down over the dry bridge in Glounthaune, to Johnstown. That old road is still there.

So the original Cork to Youghal road went through Caherlag, and a drawbridge was built over the Glashaboy River at Dunkettle at the end of the 1700's, start of the 1800's making it possible to avoid going through Glanmire to get to Youghal for the first time, and that opened up Tivoli then.

spacetweek

https://www.boards.ie/discussion/comment/118554629#Comment_118554629

In that video, two of the lanes on the new structure are M8 South. Will the other 2 be M8 north or will that be somewhere else?

AugustusMinimus

https://www.boards.ie/discussion/comment/118562618#Comment_118562618

Correct. Exiting the tunnel, 1 lane will veer slightly to the right (basically anti-clockwise around the present roundabout) and then use the west most piece of the new bridge to continue north. It means that N40 North to M8 North mainline will use the east most underpass of the N25 taken up by part of the roundabout today.

The other side (west piece of present roundabout) will facilitate a number of new movements.

hans aus dtschl

https://www.boards.ie/discussion/comment/118562882#Comment_118562882

That's the messiest piece of the whole thing for me, moving the N40 North to M8 North movement East under the existing overpass. It's the piece I really struggle to visualise in terms of traffic management.

AugustusMinimus

https://www.boards.ie/discussion/comment/118563812#Comment_118563812

Just to note that this full new alignment won’t happen for ages yet. Northbound traffic will be using the new bridge in a few weeks. However, traffic will still be using the roundabout as normal. Northbound traffic will just have a sharp left turn onto the new bridge.

In order to facilitate the final new alignment, all traffic will need to cease using the roundabout. All movement to the left are easily provided for. All 270 degree movements will need to be catered for before all north - south traffic can be fed through the east most underpass of the N25. Will be interesting to see how they do this cut over.

pad199207

How does one travel through the interchange if your going from M8 south to cork city ? Doesn’t seem clear on the graphics

AugustusMinimus

https://www.boards.ie/discussion/comment/118564024#Comment_118564024

Its the only mainline movement which isn’t free flow. M8 traffic will take the slip off to the left, go through the dumbbell interchange to the east and then join the N25 mainline to get to the Dunkettle Roundabout.

Even at peak traffic, I don’t think it will cause delays.

Chris_5339762

https://www.boards.ie/discussion/comment/118562882#Comment_118562882

I always laugh at these images and their insultingly large numbers of trees packed incredibly densely into every available space!

hans aus dtschl

https://www.boards.ie/discussion/comment/118564155#Comment_118564155

I still think that one and the pedestrian/cycle route are mistakes in this scheme. But we'll see when it's done.

This one, because I suspect that traffic to the East of the City (Tivoli) will rat-run through Glanmire. But the alternative would have been difficult/complex with lots of extra structures. I understand why they didn't go for it. And it's only one flow out of more than a dozen. And it would be about as difficult to do in future as it would during the project. So nothing major lost overall. And an M40 North would be a better way to bring traffic into the Northside anyway.

The pedestrian/cycle route was just a bit lazy and low-quality. I have great admiration for the overall project, but that bit sticks in my craw a little bit. The cost to deliver a really high quality pedestrian and cycle route would have been minimal and wouldn't have delayed the project. We can hope the proposed route to the South of the interchange progresses, solving a lot of that problem. Unfortunately a lot of things in the Dunkettle area are waiting for Tivoli to be developed, so there's a bit of a wait ahead. But all very exciting at least.

Corkladddd!!

I assume ST01 the new bridge will have a big part in the cutover? All M8S and N25E/S to be sent to this with them then being able to send traffic to Tivoli along the N24W and using the new free flow from ST01 to the tunnel. This should leave the East of the Dunkettle interchange free for M8N and all traffic for city center and Midleton using the tunnel to N25W off ramp to the current Glanmire roundabout and the coming back on themselves to Midelton. This may even be the route as the M8N gets re-aligned? All guess work, it's been a head scratcher for some time..

AugustusMinimus

https://www.boards.ie/discussion/comment/118564540#Comment_118564540

Agree. It will be some time for this revised movement is realised. Basically all 270 degree movements using the roundabouts at present will have to be realigned.

jackrussel

Are the camera feeds wonky for everyone else? Sometimes the north one loads, most of the time none load

hans aus dtschl

Just you I'm afraid. All loading without issue for me. North view slightly blurred (bad picture) but all load fine.

jackrussel

I haven’t done anything different with my phone since they knocked the cams out a few days ago. Phones up to date, have deleted the app & reinstalled it but they still don’t load. Fairly annoying

hans aus dtschl

I'm on computer browser! Probably two different systems. The app could be in difficulty alright.

DylanQuestion

https://youtu.be/4DF-NC8k6D0

Very cool video, it gives a great before and after. Is the unopened bridge at 1:14 for M8 East?

AugustusMinimus

I see the webcams are back online. They’ve started to demolish the old southbound carriageway already. The very end will remain in order to temporarily access the new bridge from the roundabout for northbound traffic.

AugustusMinimus

https://www.boards.ie/discussion/comment/118570852#Comment_118570852

That bridge is to provide access for M8S to N25 East and to the new dumbbell interchange. It gives M8S access to N8 (City), Glounthaune and Little Island via the dumbbell interchange.

Gunner3629

https://www.irishexaminer.com/property/residential/arid-40799223.html

Am I wrong to think in 5 years the dunkettle interchange will be just as congested and more measures will be needed?

snotboogie

https://www.boards.ie/discussion/comment/118573547#Comment_118573547

In fairness that development will be right in front of a planned stop on the commuter rail. I’d imagine there will be a big push for higher density and less car parking from both the city council and ABP.

hans aus dtschl

That development isn't stalled because of Dunkettle. It's stalled because the council aren't progressing the necessary local roads upgrades. There is currently no footpath to/from the development, and high stone walls with no hard shoulders and 90-degree bends. The condition of planning about Dunkettle was a minor item on the agenda. The timeline was:

Flynn looked for planning, ABP said the development shouldn't go ahead because it was a danger to the public by way of traffic hazard and because Dunkettle wasn't finalised.

Flynn went for SHD planning, ABP granted on the basis that the local roads network would be upgraded and because Dunkettle was in progress. Flynn directly pays the council lots of money "for the road".

Flynn built phase one, no local roads have been upgraded. Many houses are occupied.

Flynn now want phase two, but no local roads have yet been upgraded. I think they're within their rights to demand that the council get on with the roads upgrade, but wrong to suggest that Dunkettle was the stage-gate that enables the development.

AKA this housing development has little to do with Dunkettle. The newspaper article is either misquoting Flynn, or Flynn are trying to move on the development before they should.

hans aus dtschl

On the topic of whether Dunkettle will be a traffic nightmare again in 5 years, I don't think so. The new bottlenecks will be Douglas Little Island and Glanmire once Dunkettle is free-flow.

I'm definitely most worried about the Little Island west junction, as I've said previously on here. But as others on here have argued, it might be OK. There's a lot of room for traffic there. But that's the one, that if it backs up, could bring interchange traffic to a stop I think. But again, unlikely in 5 years I think.

hans aus dtschl

https://www.boards.ie/discussion/comment/118574755#Comment_118574755

I forget the exact numbers but they said that something like 70% of that existing development would be active transport. With Phase 1 complete, it's currently close to 0% active transport. There's no chance that development will be remotely sustainable. All IMO of course, from passing it very often. Glanmire is on its way to becoming the new Carrigaline, a traffic-locked sprawl. "15 minute neighbourhood", by car!

_Kaiser_

Drove this other other day from the M8 inbound and it was grand - only thing I'll say though particularly from watching the videos, is that the left lane for Little Island from M8S seems very short and could cause unnecessary congestion at peak times? Why didn't they just have a 3 lane bridge?

Got caught on the trip home though as the tunnel-roundabout-M8N was closed so ended up doing a scenic trip via Glanmire - oh well!

marno21

https://www.boards.ie/discussion/comment/118575160#Comment_118575160

This is a temporary layout. When it’s complete, Little Island, N25 and N8 (City) traffic will slip off to the left over the bridge under construction to the east of the new recently opened flyover. The 2 lane bridge will be exclusively for M8S -> N40W traffic.