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

niloc1951

https://www.boards.ie/discussion/comment/120275717#Comment_120275717

Agreed, forever is a long time. However, how many years after its initial construction was it that what is now the N40 had to have its roundabouts replaced by fly-overs for the mainline? The M50 widened and the Red Cow roundabout converted to a free-flow intersection.

A few years ago while driving in Germany I traveled on a single-carriageway road with grade-separated junctions and over-bridges all just waiting for the time when its upgrade to a dual carriageway or motorway might be required. That is future-proofing and spending now to save in the future. One wonders how much less it would have taken first day to do a proper grade-separated interchange at the JLT against the cost of doing the job now.

A current example of the 'shur 'twill do for now attitude' is the lack of a slip road at the eastern end of the Macroom bypass for westbound traffic leaving the N22 for the R584 and Macroom town.

AugustusMinimus

https://www.boards.ie/discussion/comment/120276079#Comment_120276079

The plan in the early 2000s was to add a few left turn slip lanes but it never happened.

RetroEncabulator

https://www.boards.ie/discussion/comment/120274014#Comment_120274014

Totally different era though. It's very hard to find examples of somewhere that's economically grown as quickly as Ireland over that period of time anywhere in Western Europe anyway.

Bear in mind the Jack Lynch Tunnel's construction began in 1995, 28 years ago and the detailed design was done closer to 35+ years ago at this stage. If you'd proposed a complex junction like that back then you'd have seemed ridiculous. The tunnel itself was considered vastly ambitious - there were no motorways, the south ring was barely completed, traffic was much lighter and the economy was much smaller. There wasn't even any certainty that the M8 would ever be built back in those days. I remember discussions after the tunnel was built about maybe doing 2+1 between Cork and Dublin... and that was even a stretch. There wasn't even a TII or National Roads Authority type organisation - every city / county council was doing its own thing, often on a really small scale.

It's doubtful we'd have even been able to afford it back then.

We've a far bigger vision of being able to do things nowadays. If you look at somewhere like Germany that vision would have existed much earlier. Ireland was scrimping by in the 80s and well into the 90s, and building things in a very piecemeal way, and with no notion of what was to come later. It would have seemed utterly unbelievable to explain our economic situation now vs the early 1990s and certainly the 1980s.

The Jack Lynch Tunnel at the time was the biggest civil engineering job done since ESB at Ardnacrusha in the 1920s. So, it's kinda unsurprising we weren't very good at planning major infrastructure. We hard hardly built any serious projects almost in the entire history of the state. The only other big projects were mostly ESB power plants, which we tended to have people droning on and on about because there was little else of significant scale constructed here for most of the 20th century.

KrisW1001

Worse than that: 2+1 wasn’t even on the cards, as that road type wasn’t adopted until the mid-2000s. The plan for N8 was to have wide single carriageway through most of the central part, with dual carriageway only at the stub joining M7 and the Glanmire bypass approaching cork.

The N8 Cahir bypass from 1991, now R639, is a good example of what was planned for most of N8: wide single carriageway, mostly at-grade junctions, but good sightlines and the elimination of private accesses onto the road.

Dunkettle is actually older than the Jack Lynch Tunnel, as it was completed in 1994, as an interchange between the N25 East Cork Parkway and the M8 Glanmire Bypass, so the traffic planning that went into its design was from a different era, really. Anyone at a design office in the late 1980s saying that the interchange would need to accommodate 80,000 cars a day within 30 years of opening would be told lie down until they came to their senses - there were only 220 cars per 1000 inhabitants in Ireland in 1990; that figure is now 440 per thousand, and on top of that the population has increased too from 3.5 to 5.0 million.

RetroEncabulator

It wasn’t in existence here, but similar systems were common in Scandinavia, and it was very much discussed as an example of a number of cheaper way to do long distance roads with low traffic. The only examples ever rolled out here were very limited, but plenty of options were discussed in civil engineering circles etc.

If you look at the discussions in the late 80s and into the 90s the road network ambitions were basically a number of bypasses and high quality single carriageway, removing the accident black spots. It was cheap.

The M50 was under sized, but again planned before the Celtic Tiger, but the Cork junctions being done on the scale they are now would have been seen as totally insane in those days.

It’s very easy to look back on the 80s and 90s from the perspective of today. It was an entirely different country economically. There was neither the budget nor the notion of this level of growth. The same applies to most of our infrastructural legacy penny pinching / lack of investment.

hans aus dtschl

https://www.boards.ie/discussion/comment/120275265#Comment_120275265

November 2017: Less than 6 years ago! The active transport route design was appended after the overall design was done. It was very much an afterthought.

The original design had people running across the M8 (Tivoli to Dublin) slip road using an unmarked crossing (I wish I was joking). The NTA demanded a change from the design team, so the next "minimum viable product" was chosen.

AugustusMinimus

It’s actually mad to think that up to 2 years ago when the new path opened, that there was no viable way for a pedestrian to get from Tivoli to Glounthaune without walking through Glanmire.

hans aus dtschl

People walked on the slip roads!

It's still a horrible route to cycle tbh.

AugustusMinimus

Great video.

https://youtu.be/D_X2bfwD8eQ

Chris_5339762

Anyone know what happened today?

3 car collision at Little Island this morning - presumably stupidity. (I was lucky I checked Google traffic that morning, just before it happened, and went through Glounthaune before anyone else copped it!)

But what happened later in the day - they closed a lane on the N25 westbound - was it related to this? Seemed to cause chaos all over again. To me it seemed like emergency work.

cantalach

https://www.boards.ie/discussion/comment/120281390#Comment_120281390

They sent out an update by email about that around lunchtime today. Text below.

“A lane restriction is in place on the N25 westbound in the area of Junction 2 Little Island. The restriction is required to facilitate completion of surfacing works in the area immediately west of Little Island Junction. All traffic lanes in this area will reopen fully at 05:00am on tomorrow, Friday 24th of February 2023. Additional time should be allowed for westbound journeys in this area during the evening peak today.”

mcburns07

https://www.boards.ie/discussion/comment/120281390#Comment_120281390

Went via the back roads from Carrig to Glanmire too, saved half an hour.

gooseman12

https://www.boards.ie/discussion/comment/120280844#Comment_120280844

looking at that, you would have to think that the next piece to open will be the tivoli to tunnel loop, they seem to be making massive progress with it.

AugustusMinimus

https://www.boards.ie/discussion/comment/120282601#Comment_120282601

I’m actually shocked at how advanced it is. Will be interesting to see how they do the temporary tie in with M8 mainline traffic.

Chris_5339762

https://www.boards.ie/discussion/comment/120281591#Comment_120281591

They did, but that didn't fit for me. I saw the newsletter and though, nah. They've strictly done all of their resurfacing at night on this section, but yet all of a sudden they need to do works at rush hour. I saw them replacing steel barriers when I passed last night going the opposite direction, so I figured it was some emergency work or something like that.

cantalach

https://www.boards.ie/discussion/comment/120282703#Comment_120282703

Sure, I wasn't really offering an opinion either way. I was just letting you know that they had sent out an update yesterday because your original comment didn't mention that so I thought you might be unaware. It certainly was weird to suddenly do online resurfacing in the middle of the day.

cork_south

They also sent a notification out on the Dunkettle app about the surfacing work yesterday.

Not sure they could have done much more.

titan18

https://www.boards.ie/discussion/comment/120284066#Comment_120284066

Not doing it at peak time on of the peak days would be a start anyway. If there was an emergency, fair enough. If they scheduled it, they're dumb imo.

Chris_5339762

Thats why I'm leaning towards emergency works myself. They haven't been dumb about any scheduled works during the peak really

cork_south

I'm more disappointed that the right hand lane coming out of the tunnel north bound is still closed weeks after they said it would reopen.

Though most traffic is using the left hand lane reopening would definitely help at peak times with the tailbacks.

Risoc

I’d have thought the tunnel slip towards Tivoli would’ve been a simple section that could’ve been completed some time back.

cork_south

https://www.boards.ie/discussion/comment/120296264#Comment_120296264

Link B, yeah they said it should be opened by today in the newsletter last month.

Hopefully be ready next week.

General roadworks are underway at Link B – 
see photograph below. We still hope to open 
Link B & Link I to traffic before the end of 
February 2023 

AugustusMinimus

https://www.boards.ie/discussion/comment/120296574#Comment_120296574

It’s nowhere near complete from what I’ve seen. It’s like work was abandoned on it. Suspect it’s at least a month off opening.

serfboard

https://www.boards.ie/discussion/comment/120297084#Comment_120297084

City to tunnel looks to be having more work done to it than tunnel to city.

AugustusMinimus

https://www.boards.ie/discussion/comment/120297999#Comment_120297999

Certainly looks that way. I would say both are about as advanced as each other.

Chris_5339762

Since City - Tunnel will allow the removal of one set of traffic lights on the roundabout, and with the Tunnel - City movement stymied by traffic at the lights at the mouth of the tunnel, I'd say those two are quite interlinked.

confidentjosh

https://youtu.be/W2_X5UnbWb0

New DroneHawk video: March 2023 Update

Chris_5339762

Good ole Dronehawk... though he's a bit more sensible than his early years when he was diving underneath everything he could find!

More work to do than I expected on N25W to tunnel, even the likely temporary tie-in via the new slip to the current traffic lights. The Little Island south roundabout to N25W can't be touched until that diversion opens, and the N25W to M8N embankment can't be finished until all of that happens because you can't just really close the current route out of Little Island close to the tunnel management building.

They have 11 months left, but bits and pieces could be a tall order in that time.

Tivoli - tunnel is very nicely advanced though, hopefully that won't be more than a few months max.

marno21

https://www.echolive.ie/corknews/arid-41082173.html

Really getting there now.

KrisW1001

https://www.boards.ie/discussion/comment/120304170#Comment_120304170

Good old Echo, use a picture of the old interchange on a story about how the new one is coming along...