N40 - Cork South Ring Road upgrade [early planning underway]

marno21

https://atkinsireland.ie/news/atkins-to-lead-n40-ten-t-transport-infrastructure-improvement/

I have been meaning to create this thread for months but TII have this listed as a major scheme now so it definitely merits a thread.

To sum it up, this scheme seeks to identify opportunities to improve/streamline the N40 after two major changes:

1. The completion of the Dunkettle Interchange upgrade
2. The construction of complementary infrastructure from CMATS (mainly the Cork Southern Distributor Road)

It'll be interesting to see what's proposed here. Anyone pro-road infrastructure will likely suggest a third lane between J9 and J6 westbound, simply because there will be 2 freeflow lanes coming from Mahon/Dunkettle and 2 freeflow lanes coming from the M28.

hans aus dtschl

"Anyone pro-road" isn't quite right here Marno. I'd wager anyone pro-road would be in favour of an N40 North. Another N40 South lane is just a sticking plaster.

N40 south is now a single point failure for all citywide traffic. Another lane will work fine until a crash and the whole city will gridlock again. We need alternative routes, not slightly more capacity on the current route.

We also desperately need modal shift, but that's a much bigger topic. And woe betide anyone who suggests it.

marno21

https://www.boards.ie/discussion/comment/120499499#Comment_120499499

I should watch where I put my punctuation, I meant pro-road infrastructure as part of this solution. IMO widening the N40 anymore along the mainline would be a futile exercise, but I can't not suggest widening a 2 lane section sandwiched in between a 4 lane (N40 + M28 terminus) and 3 lane section. IMO it's a clear lane drop equivalent to having a lane drop on a busy section of the M50.

IMO N40 North is important, but the Southern Distributor Road would be even better. Removing local traffic off the N40 would be a great start

Modal shift would be fantastic but it's a lot to ask for in a city like Cork on a road like this, much of the traffic is going nowhere near the city centre which is where the modal shift will be best achieved. PT from Ballincollig to Mahon for example will never beat the journey time for a car travelling along the N40.

KrisW1001

I am pro road infrastructure, but I would oppose any further widening here unless it was as a part of a complete redesign of the Douglas junctions - any widening here would be really expensive, and that money would be wasted without also (or first!) addressing the root cause of the problem: that the N40 is double-jobbing as a relief road for Douglas along this stretch. The problem needs a more adventurous approach than just throwing more lanes at a crap design.

The Southern Distributor is essential for any improvement here, and I guess it’s the main thing they’re referring to by “complementary infrastructure”.

As for Public transport Ballincollig to Mahon, if you include the time taken queueing on the exit roads from M40 and then finding parking around Mahon, a bus heading cross-city on its own dedicated way would be in with a good chance of being a better option. Unfortunately (if you’ll excuse the brief off-topic) Cork BusConnects has proposed exactly zero corridors that could facilitate an orbital route:

hans aus dtschl

Yep I think we're all roughly on the same page. A Southern distributor is critical. But don't discount a Northern N40 either. A lot of people are commuting from North of the river to Ballincollig and the West of the city via the N40. It's their only real option at the moment.

And in terms of Modal Shift we probably should decamp to another thread, but the amount of city traffic on the N40 is likely very large. Almost anything going to Mahon uses the N40, almost anything going to UCC, CIT, CUH, Airport, Douglas (all large trip generators, all within the city) are using the N40 by default. I don't agree that much of the traffic is going nowhere near the city: I'd wager a high proportion of the traffic is going to the city. It could even be 50%. It would be great to get the analysis of this, but I'd be willing to wager that half (or less) of the traffic on the N40 is bypassing the city.

The N40 double-jobbing as a distributor is THE problem. Another N40 lane cannot be the solution. Different roads and different modes are needed. If nothing else, the single point of failure is too significant now: when the N40 stops the city completely stops.

And just pointing out that I'm not saying "no more roads" here at all, I'm explicitly saying Southern Distributor and Northern N40. But I really think that our efforts at modal shift to-date have been absolutely pitiful. BusConnects low-aspirations getting scaled back is kind of indicative of our current "moar cars" philosophy.

AugustusMinimus

Do we have a South distributor road thread?

hans aus dtschl

https://www.boards.ie/discussion/comment/120500142#Comment_120500142

I don't see one, and much of the talk of a Southern Distributor that I've seen has been in the anti-M28 groups' "alternate proposals"!

Possibly worth setting one up?

kub

Whatever became of the re designation from N40 to M40, does anyone know?

KrisW1001

Unlikely until there’s a viable and safe East-West route for slower heavy vehicles. Right now, the only alternative route would involve going into the city centre.

Chris_5339762

https://www.boards.ie/discussion/comment/120500142#Comment_120500142

Yup, here is is -> https://www.boards.ie/discussion/2057981513/cork-southern-distributor-road-route-selection

hans aus dtschl

https://www.boards.ie/discussion/comment/120502434#Comment_120502434

Yep seems to have quietly disappeared. That one seemed really crazy to me, at the time.

Jayuu

Moved this from the Southern Distributor thread as it seems more appropriate here.

Can I ask has there ever been any consideration given to a link between Cobh and Passage West or Ringaskiddy in order to provide an alterative route to the N40? Either a bridge or a tunnel.

The river is quite narrow all along here but are there particular geographical constraints that would make this impossible or costly that I'm not aware of, or simply not just enough traffic to justify a crossing?

It just always feels to me that looking at a map of Cork and surrounds there is a huge problem in South -> East or West -> South traffic all having to use the N40/Dunkettle as their only option for travel. Maybe that's not a large amount of traffic but given the seemingly constant pressure on the N40 and given the M28 project is something like this viable?

AugustusMinimus

Did a thread on this a few years ago. Could easily be tied in with the construction of a tidal barrier.

https://www.boards.ie/discussion/2057819773/monkstown-to-rushbrooke-bridge#latest

hans aus dtschl

I don't think a tidal barrier is workable there. I read the OPW analysis paper which was trying to discredit the idea of tidal barriers of the Lee. They said that the channel there is too deep and narrow and fast so a tidal barrier would be very difficult if not impossible.

They pointed at a tidal barrier from Little Island to Passage instead, with supporting works to the North of Little Island. I know we're very much cross-threading here, but I like this idea, and think it could be powerful. The amount of greenway commuters who would cross to Little Island via such a route would be reasonably large, and I'm confident it would take N40 users off the road. The OPW analysis paper said that it would cost approx. 1 billion euro (this was maybe 5 years ago, so probably a good bit more now due to inflation).

For the link directly to Cobh, I'd prefer to see the roads and footpaths on either side of the river upgraded first, they're narrow and in very poor condition. Next I'd prefer to see the new Belvelly/Rossleague bridge and Fota Road done. With that complete, the existing ferry could potentially begin to operate more hours a day and the logical case for a down-river bridge could be made. But it would need to be something like the New Ross bridge in terms of scale, and I don't think the traffic movements warrant it unfortunately.

But on the other hand, and I apologise in advance for the off-topic section below, there's so much low-hanging fruit in terms of sustainable transport in the Cork area I think if we're seriously looking at tidal barrier bridges and large extradosed cross-river bridges etc (I still want these!) then we should surely also at least start a more honest conversation about modal shift.

On that note a really simple low-cost consideration to alleviate some tunnel traffic could be a small passenger ferry from Mahon to Little Island. I see lots of these little passenger ferries crossing the canal/river in Amsterdam and it seems like a really simple cheap thing to do. The existing "tour" boats on the Lee could almost do it if jettys were made. Hopefully my link works, but here's what it looks like in practice: https://www.google.ie/maps/@52.3824052,4.9031825,3a,60y,220h,86.51t/data=!3m6!1e1!3m4!1swWqjimi1f2Uj-bBhD0-Yjw!2e0!7i16384!8i8192

You could do something similar from Cobh to Ringaskiddy maybe. But even then, and as I said above, I'd prefer to simply see the roads and footpaths on either side of the river upgraded first. It's actually extremely uncomfortable to walk or cycle in Cobh/Passage/Monkstown/Raffeen. We're forcing people into cars by making every other mode so difficult. Even a really simple thing: Carrigaloe train station from Carrigaloe ferry is a very uncomfortable 700m walk/cycle. Why not link these two, and try and entice Passage/Monkstown/Ringaskiddy commuters onto the train? Why not properly link Little Island train station to the employment centres by footpath and cycleway and maybe even shuttle bus?

Each of these takes a small % of end users out of the tunnel, or off the N40 or both.

DylanQuestion

As mentioned previously, the N40 was built as an east to west link, from Mahon to Bishopstown, using a lot of existing land from the Bandon Railroad. The name South Ring suggests a bypass (and the tunnel now allows for a reasonable bypass of the city centre for some N-S traffic), but ultimately it isn't a bypass. As someone else said, I bet most users of it are those living in the city and just commuting to other parts of it. That person mentioned trips to Mahon and Wilton - how could you do this journey in a reasonable way without the N40? I live in Maryborough, south of the N40. To go to Wilton, I'd have to go down to Douglas, over to Turner's Cross, Ballypheane and then Glasheen. To get to Mahon, I'd have to go down to Douglas and use the congested, relatively residential Well Road and Skehard Road. Realistically, no one in the south city outside the N40 is going to do that. Therefore, the N40 does act as an East - West link, but instead of being for HGV coming from the tunnel onwards to the west of the county/Kerry or east of the county/Waterford/Dublin and wishing to avoid driving local city roads like Douglas Road, Skehard Road, Western Road, etc, the N40 is primarily (I would argue) a local distributor road. I'd like to know how many routes start within the city (I mean the urban city, not City Council area) and end in it. Probably a lot.

First things first, they need to limit the number of junctions onto the road from within the city. Some can't be removed, like the Rochestown junction (as the R610 is already congested enough as is). However, J9 Douglas (West) comes to mind straight away. Commuters using that don't have to travel far to access the three destinations I would consider the primary destinations of the N40: the City Centre, Mahon and Wilton/CUH. For cars coming from Mahon, close the eastbound exit, meaning cars coming from Mahon will only use the N40 to access the tunnel. Close the on ramps at J6 Togher, J3 Bishopstown (East) and J2 Bishopstown (West) for the same reasons as J6. Yes, that will push a lot of cars that would have been using the N40 onto local roads, however this should be done with two changes: the Southern Distributor and BusConnects. I don't believe the Southern Distributor should follow the R610/R853/R641, mainly because the neccessary link at The Mangala will never happen. It should start at Mahon/Jacob's Island, cross a new bridge from Jacob's Island to Rochestown Road, run from an ugpraded L2474 Monastery Road, along a new road to the Carr's Hill interchange, to Elm Hill, meet N27 Airport Road at an upgraded interchange and run along a new road connecting to the N71. This would be a true bypass of the southside, as well as being a distributor road that HGV wouldn't be using. The N40 then can return to what its primary function is (an inner city bypass for E-W traffic)

This provides direct local access to the main trips the N40 is used for - Mahon, Wilton and the airport, as well as the City Centre via the N27 Airport Road Interchange, West Cork via N71 Viaduct Interchange and Carrigaline/Ringaskiddy via the N28 Carr's Hill Interchange. As mentioned above, this could also tie in with a ferry service from Mahon/Jacob's Island to Little Island. Thoughts?

hans aus dtschl

https://www.boards.ie/discussion/comment/120515344#Comment_120515344

I don't like the Easternmost piece of this, because I think it's possibly too near the N28 to be of significant value, considering the effort.

What you're drawing here seems to be more like a Bypass which is easier to map out but much harder to use as a distributor unless you basically zone all the land around it for development. Not necessarily a bad thing to do a Bypass instead of a Distributor, but I think the bang-for-buck with a distributor will come from routing it closer to the urban areas. And I don't think the cost/benefit for a southern orbital bypass is going to be good.

I guess I'm saying: it needs to be a distributor, leaving N40 as the "bypass" whereas what you're proposing will work quite well as a bypass. This would potentially be a desirable HGV link from the West of the city to Ringaskiddy, so I'd worry about that for instance.

I think you're calling it perfectly though, N40 is used for Little Island/Mahon/Douglas/Airport/Wilton urban traffic. That's definitely the primary job it's doing right now.

Pete_Cavan

https://www.boards.ie/discussion/comment/120515344#Comment_120515344

If going to the trouble of building a new road further south, then it has to be the bypass, not the distributor road. The distributor road also has to cater for active and public transport which would be pointless so far south. If you had a new bypass, the the existing N40 could be reengineered with reduced traffic lanes and possibly even accommodate a light rail system.

DylanQuestion

The City Council has begun a consultation to extend the westbound off ramp at J10 Mahon/Blackrock/Jacob's Island by converting ~750m of the existing hard shoulder. They state that this is needed as the hard shoulder is used as an informal off ramp lane during busy times, and they expect this to increase after the Dunkettle Interchange works

https://consult.corkcity.ie/en/consultation/extension-n40-south-ring-road-ramp-westbound-approach-mahon-junction-10

kub

https://www.boards.ie/discussion/comment/120533622#Comment_120533622

I thought a project like that, on a National Road would be the responsibility of the NRA ?

AugustusMinimus

https://www.boards.ie/discussion/comment/120533622#Comment_120533622

I think they’re expecting bigger queues back from Bloomfield and this will allow better Mahon to Rochestown movements when traffic is queuing.

hans aus dtschl

I think this also speaks to what most of us believe on here, and the purpose of this thread: Dunkettle will likely allow more traffic to reach the Douglas area and we're not going to "More N40" our way out of this in the near future.

legend99

Difficult to disagree with the view that says 2 lanes from M28 and 2 lanes from tunnel will simply lead to huge problems at Douglas flyovers and indeed at Kinsale Road given that so much traffic exits at the roundabout there?

Do I recall that footings were put in when Douglas Village Shopping Centre was rebuilt to allow for a third lane heading West? And the flyover is build for 3 lanes (it has the 3 if going East) so I assume there was a plan in that case to widen to 3 for Westbound?

marno21

First part of this jigsaw approved

https://www.echolive.ie/corknews/arid-41184922.html

cantalach

https://www.boards.ie/discussion/comment/120861145#Comment_120861145

And of course The Echo shows a photo of the western side of the junction which has almost no relevance to the story.

lawrencesummers

So the cost of road building now is 3.3million per km plus land purchasing cost of which there are none here.

Great little country this

hans aus dtschl

https://www.boards.ie/discussion/comment/120548056#Comment_120548056

I don't know for sure, but I believe you may be mistaken. I don't believe that the space is available, nor do I believe that the infrastructure you mention was put in place. Again, I'm not speaking from a position of any certainty.

DylanQuestion

Looks like this is no longer being referred to as the South Ring, instead just being called N40. TII are in the process of updating directional road signage in the city, including updating old N25 signage to N40. Signs that once said N25 South Ring, such as the N20 on Carrol’s Quay, now just say N40. Even new signs that said N40 South Ring at Albert Quay and Victoria Cross have been replaced by just N40 with ferryport and airport symbols. It will be interesting to see what they do with the “Use South Ring Route” signs on Horgan’s Quay, Cathedral Walk and Carrigrohane Road (which still refer to the N71 as for West Cork, and the R610/N28 as the R609)

marno21

https://www.boards.ie/discussion/comment/121495680#Comment_121495680

Open to full correction here, but that type of destination signage was done away with when the TSM was updated about 10/15 years ago. So called "super destinations" were removed (you see similar signage around the Quays in Dublin with the N4/N5/N6 signed as "The West" and the N7/N8/N9 signed as "The South"). The N40 is signed by its number only now (it was more difficult to sign accurately when it was the N25 as this was both the South Ring and the road to Waterford/East Cork), and the N71 is signed as "Bandon" or "Skibbereen".

The destinations to which these roads are to be signed can be found in the TSM/Roads Act.

Chris_5339762

I also look forward to seeing what they do with this disaster.

https://maps.app.goo.gl/QofXi24BANS2ewKC9

Clean it, hopefully.

marno21

https://www.boards.ie/discussion/comment/121496688#Comment_121496688

At a guess, that sign is a relic from when the "South Ring Route" went from Bishopstown to Rochestown and N8/N25 traffic had to use Horgans Quay & the South City Link Rd to access the 4 destinations above. The R600 & R609 route numbers being used would indicate its a mid 1990s sign at the latest.

It could be debated that there is no such need for a sign like that anymore.

DylanQuestion

https://www.boards.ie/discussion/comment/121495766#Comment_121495766

There was N40 South Ring signage added between 2014 and 2017 that has now been replaced by signs just as N40. Would that be considered a super destination too?

https://maps.app.goo.gl/9Bt2GYqAL3xcsfAp9

https://maps.app.goo.gl/o3ka34Xh8GEQkyZq5