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

hans aus dtschl

https://www.boards.ie/discussion/comment/121826680#Comment_121826680

Thanks for all the info and context. What you're explaining about political wrangling is is the piece that I was reading about last night, it's almost difficult for me to remember how bad things were.

How far we've come!

gooseman12

https://www.boards.ie/discussion/comment/121827083#Comment_121827083

Ya, I've had the same experience coming from the N8 loop. The cars coming straight down the hill from the M8 have no reason to slow down to 60. If everyone was doing 60 there would be no issue whatsoever on the merge, its all about the speed.

As someone else mentioned earlier, it really is a prime candidate for a fixed speed camera

jhegarty

There is video of proposed two tunnel mentioned above here : https://www.rte.ie/archives/2022/0110/1272861-river-lee-tunnel/

niloc1951

https://www.boards.ie/discussion/comment/121827205#Comment_121827205

The issue is down to a lack of courtesy, here in Ireland there seems to be a general attitude among drivers to actively make it difficult for other drivers to join the mainline from a slip road.

I do a lot of driving in western Europe and the opposite to the above is usually true. Drivers on the mainline will usually ease up or speed up to create a gap for joining vehicles. It's rear to have to slow down on the slip because there's no gap on the mainline.

hans aus dtschl

https://www.boards.ie/discussion/comment/121827599#Comment_121827599

Also some lovely images there of what I presume was LUTS 1978 too thanks!

I'm actually becoming disheartened to see how good LUTS 1978 was: we've had these visionary ideas available for a long time but have ended up with everything that LUTS tried to avoid. We got Dunkettle and the M8 and the N40, that's phenomenal, but it looks like almost everything else has slipped.

EnzoScifo

I remember there being a lot of controversy and even pictures on the front page of the echo claiming that toll booths for the tunnel were being installed before opening.

Hibernicis

https://www.boards.ie/discussion/comment/121834893#Comment_121834893

The original plan, back in the 80s, was for it to be tolled. I think it was to be 25p or something. This was necessary to fund construction. It became unnecessary when the Germans kindly decided to pay for our roads in the 90s. That of course hasn’t stopped the Echo dragging it up every few years on slow news days and that windbag Terry Shannon seeking voter enrichment from time to time by calling on “the minister to confirm that a toll will not be introduced” when there hasn’t been any mention of it anywhere except in his head.

cantalach

https://www.boards.ie/discussion/comment/121836676#Comment_121836676

Ah why did you have to mention Terry Shannon and wreck my chilled out Sunday morning mood…I felt my blood pressure jump right away.

DylanQuestion

A City Council Consultation has started about Special Speed Limit changes in the city, and it includes Dunkettle’s speed limits

https://consult.corkcity.ie/en/consultation/cork-city-road-traffic-special-speed-limits-bye-laws-2024

Looking at the map, it seems:

• Before the tunnel and in it will go to 80km/h
• 60km/h everywhere else except the N25 flyover where it will be 80km/h
• The M8 will go to 100km/h from the N8 slip lane

This only includes City speed limits. It doesn’t include what the speeds will be on the N25 in the County section (the boundary is just west of the dumbbell) but it seems to suggest it will turn to 80km/h there. I’m not sure where it will change to 100km/h and 120km/h

Chris_5339762

Isn't that pretty much what it is at the moment?

Not that any of them are ever enforced or obeyed in any sense...

jhegarty

I don't see any reason for the flyover not be 100 kph or for anything less than 80 after leaving the tunnel heading north.

DerMutt

I never thought I'd be suggesting an actual reduction in the speed limit but the section of Link C where it dips and turns under the N25 overpass is scary at anything close to 60 kph in a double deck artic! It should be reduced to 50 kph for that section or some poor trucker could end up on their side over the concrete barrier and on top of traffic exiting the tunnel heading for Waterford!

mackerski

https://www.boards.ie/discussion/comment/121849848#Comment_121849848

Could the trucks not just voluntarily drive more slowly to suit the conditions?

_Kaiser_

https://www.boards.ie/discussion/comment/121859023#Comment_121859023

This, and as a general rule too.

There's far too much dependency in this country on "someone else" to do the thinking/decision making for them.

Driver's should have the awareness and cop on to assess a given situation and react appropriately - sometimes that might mean slow down, sometimes it might mean speed up.

This infantalisation of society and lack of person responsibility/accountability is a big problem, as is the decision then to pander to this lowest common denominator and force everyone else to accomodate them.

Corkladddd!!

Interestingly I was told by someone today that I'd rely on for these things that there is acknowledgement within TII on the N25 to N40 connection being undersized for current traffic volumes and that while the captial project is closed the overall project will remain open with some potential on road upgrades to be considered. Would this be a zip merge?

jhegarty

Mad idea , but close the Little Island entry from 7am to 10am and send them this way :

https://www.google.com/maps/dir/51.9018725,-8.378833/51.8930864,-8.3922049/@51.9047031,-8.3903699,16.75z/data=!4m2!4m1!3e0?entry=ttu

niloc1951

https://www.boards.ie/discussion/comment/121866194#Comment_121866194

The idea of zip merging has had a lot of air time here already.

However, the fundamental problem of fitting two lanes of traffic from the N25 arriving at 100kmh plus a third lane from Little Island into one lane travelling at 60kmh will always lead to queueing once a certain volume of arriving traffic is reached, no matter how they are integrated into one lane.

The only way to reduce the queueing is either increase the speed of traffic through the single lane bottleneck that connects the N25 to the N40 which might compromise road safety or add a second lane connecting the N25 to the N40 which would require a another tunnel.

KrisW1001

There will always be queues at peak demand times. The interchange has reduced these queues overall, but that really wasn't its main purpose.

The whole point of this work was to stop heavy traffic on one approach to the interchange from blocking all the other approaches too. In this, it has definitely succeeded.

The other way to decrease the queuing is to give commuters an alternative to driving on N40 at all. Adding more lane capacity for private cars is a hiding to nothing: we could lay a second tunnel here, but then Douglas would be the problem. Knock down the shopping centre, widen Douglas, then we'd have "problems" at Kinsale Road again, and so on. And all those extra lanes just to achieve the same throghput as shifting 20% of car commuters to public transport.

niloc1951

https://www.boards.ie/discussion/comment/121869074#Comment_121869074

I'm a regular user of public transport, both bus and train. Several issues need to be addressed to encourage more people to switch from cars to public transport.

Busses are notoriously unreliable and one can have no confidence in arriving at one's destination at the expected time. In this respect, trains are a far better option.

The issue of loutish behaviour needs to be addressed, there is nothing worse than having one's personal space invaded by others playing loud music or video on their phones or regaling friends, and the rest of the passengers, with an account of the previous night's debaucherous behaviour..

KrisW1001

Agree that there's a way to go on Public Transport, but it's far cheaper than constantly building roads. Bus punctuality is a huge problem in Cork, and one that TFI seen to be doing very little to address. The "real time" data that feeds its apps should be a real help, not it is clearly based on estimates rather than real GPS data, and has frequent "phantom buses" that never come. Plus, buses can and do arrive up to three minutes before their due time: leaving a stop early is the worst sin for any kind of timetabled service..

Dunkettle was needed to remove a flaw in the road network (the single, shared point of congestion that was the roundabout). The next step here will be N40 North to relieve the South Ring, but there's nothing more that can be done effectively south of the river.

Hibernicis

From Roundabout to Interchange

Something for the next rainy day. A few recently published retrospective videos. While all are interesting, I found the interviews with Richard Bowen and Val Fox particularly revealing, giving an insight into managing the layering and complexity of the project.  

Dunkettle - The Ultimate Construction Timelapse - Part 2 (@dronehawk)

https://www.youtube.com/watch?v=nmXVkWrveyo

Dunkettle - The Ultimate Construction Timelapse - Part 1 (@dronehawk)

https://www.youtube.com/watch?v=S9FMc9uID8s

Dunkettle - (3 Years in 3 Minutes) (@dronehawk)

https://www.youtube.com/watch?v=IE-vbnUgNh0

Dunkettle Interchange Evolution during the Construction Period (TII)

https://www.youtube.com/watch?v=3zwBWSE7ZAc

Dunkettle Interchange Upgrade - Evolution during the Construction Period (TII)

https://www.youtube.com/watch?v=-tl3Uh7scLA

Dunkettle Interchange Upgrade – The Challenges faced during the project

TII - Interviews with Richard Bowen, Senior Project Manager TII, and Val Fox, Regional Director -John Sisk, the Main Contractor.

https://www.youtube.com/watch?v=atDqPWrSh9I

BagofWeed

https://www.boards.ie/discussion/comment/121869534#Comment_121869534

I spent most of the week on PT on the continent and I hate to break it to you but noise, music and conversation were the order of every trip. There were even folk drinking spirits on a train yesterday morn and you know what nobody gave a ****. Even the drinkers cleaned up and took their shot glasses when they arrived at their stop. There were loads of old school gabbers on the trains coated in tattoos and they were all minding their own business. Even the train conductors were chatty and being friendly and not looking down their noses at people drinking and listening to music, talking etc.

Ireland has become this horrible stuffy stifling place in the last ten/fifteen years.

niloc1951

https://www.boards.ie/discussion/comment/121872260#Comment_121872260

Nicely put. An excellent argument why many people are so reluctant to give up their own personal space free from the unwanted intrusion of others as is provided by the car.

BagofWeed

https://www.boards.ie/discussion/comment/121872650#Comment_121872650

Car is king. And none of what I wrote about was preventing other passengers from reading books or children commuting from school. Despite the fear and paranoia that runs through Irish life none of what I wrote about had appeared to intimidate or cause distress to any other passengers either. A sizeable amount of folk here are just anti people in general and will never fell safe around groups of people, no matter wheter it's on public transport or walking around a city/town centre. Got off at a metro stop in De Pijp and there was kids no more than 5 years old on their own getting onto the metro and I just thought there and then that back here people would freak at the idea of young kids using public transport on their own.

niloc1951

https://www.boards.ie/discussion/comment/121873420#Comment_121873420

Apologies for being so far off topic, but maybe it's not considering it's in a way about the ongoing traffic congestion at Dunkettle.

I do know that mass transport systems can be rammed full with all sorts of people, I've used them too, and in general people seem to be quite respectful of others and not at ail intrusive.

My point is, after a busy day the choice for the commute home is between the peace and quiet of the car while listening to your favourite radio programme or music or maybe having a quiet chat with your passengers against a seat, or maybe standing, in public transport while having to put up with the intrusions and sh1te talk from some fellow passengers who have no regard for others.

Chris_5339762

I will add also that despite all of the accidents at the N28/N40 merge, there is now absolutely no crashing happening at Dunkettle really. And importantly if one route gets blocked, it doesn't block the entire roundabout with consequences for uninvolved directions of traffic.

Remember the days when the N28/N40 crash would pile up to the roundabout, proceed to block the entire roundabout, resulting in traffic back to Sarsfield Road? Can't happen anymore, which is great.

crossman47

I am not familiar with this interchange but the signs sent me astray recently. I have to drive from Dublin to Carrigaline soon. As I come in on the M8 , is it straightforward to enter the tunnel to get onto the M40? Any advice welcome.

hans aus dtschl

https://www.boards.ie/discussion/comment/121879958#Comment_121879958

On the M8, just stay right.

After the tunnel, second exit for N28.

DylanQuestion

https://www.boards.ie/discussion/comment/121879958#Comment_121879958

Follow every sign for Westbound then, as hans said, take the second exit (J8) for N28 to Carrigaline. At the Bloomfield Interchange, keep following the signs for N28. At the next big roundabout (Shannonpark), which you should reach after ~5 mins if there's no traffic, it's the second exit (R611)

_Kaiser_

https://www.boards.ie/discussion/comment/121879958#Comment_121879958

Once you get close to the interchange move right and stay there as you pass through it and the tunnel itself.

Next exit is Mahon. Continue on but after that move far left and take the exit (it's very much like the M50N to N7 exit in that regard in terms of how it functions)

As you come off the slip, move right one lane and continue on this road until you pass a Maxol garage on your left and then get to the roundabout (Shannonpark). You are going right. Note that this roundabout is a mess with 2 right turn lanes merging into one exit and leads to racing/overtaking mid-turn.

Anyway... continue after the roundabout and go through the lights and then through the next 3 roundabouts. You'll pass a Circle K, another Maxol and the Church as you do this.

You're now in the centre of Carrigaline.