N40 - Cork City Northern Transportation Project (formerly North Ring Road) [feasibility study]

Looks small though? I assume this project is to distinguish the demands for bypass/distributor/both, right? I really hope it's both, even if the distributor is mostly just an upgrade of the existing North Ring Road.

I would also have said M20 should have started in Glanmire, but I think the M20 budget already caused problems, so I understand why it would have been left behind. It is a fairly glaring omission in the network though: the idea of HGV's traipsing through the city to get to the port, is crazy.

I have my doubts though that the CNDR will be built. Or if it is, it will still have to come through the Tivoli junction... theres no-where else for it to join up unless you take it east of Glanmire.

I hope it doesn't get built TBH, we need the grade-seperated CNRR N40, and if the CNDR gets built, then they'll use that as an excuse not to build the CNRR.

In its original concept it goes from Tivoli, Fob and Gill, cuts North to cross the Banduff Road, Rathcooney Road and West to join Ballyhooly Road, Lower Dublin Hill, crosses the train line just north of the River Bride, and then cuts sharply South-West to join the middle of the Lee Road. That's CMATS 2019, page 88. It's shown distinct from the bypass, there.

Next concept is from the Cork City Development Plan 2022-2028 page 130 Volume 1 Chapter 4, which would cover the above but also covers the entire area of the theoretical M20/M8/M40 "connector" bypass, if that makes sense. This plan describes it as a development enabler for the North of the City, providing an orbital route for pedestrian, cycle and bus. However they also say that it will allow the downgrading of national routes entering the city. This version is a lot more fuzzy. But crucially, they describe it as distinct from N40 North, and they go into great detail about N40 North. They intend to follow CMATS.

As Hibernicis above says, I think both are necessary and both should be built.

Exactly as you say, I'd actually prefer to see the M20/M8/M40 done first, or both at the same time because I'd expect a bypass to be put on the very long finger and I'd expect the distributor to become clogged up quite quickly with M20 and M8 traffic otherwise. We'll see what happens!

N40 North Ring is safe. It is a genuine bypass of Cork City, with only three intermediate junctions between its start on N8 and end on N22, and, as it links N20 with N8 and N22 it will take national traffic to and from Limerick out of the north side of Cork city.

Actually, I think that, if traffic is kept at current levels, this road would be environmentally neutral in the long term. The better road geometry and lack of stop-starts means there will be lower emission from vehicles traveling on the new road versus taking the old route, but against that there is a lot of CO2 produced by its construction. I’d like to see someone actually doing these calculations, but I suspect that in cases like this where the existing route involves steep inclines and multiple stops and starts, the motorway actually pays back the very high CO2 cost of its construction by lowering CO2 emissions of HGV traffic making the journey*

But I did say “if traffic is kept constant”... The environmental bogeyman with new roads is not the road itself, it’s the induced demand for private-car commuting that it creates. Private commuters are the biggest, and least manageable, source of transport CO2 emissions, so we (as a society) need to be careful that we don’t do things that encourage such an environmentally costly behaviour. Now before anyone has a Clarkson moment, that is not the same as “we must ban cars”; it’s a recognition that we have to come up with better alternatives to commuters than joining a traffic jam every morning and evening. Electric cars won’t solve this: a traffic-jam of EVs might not be as environmentally wasteful as one full of cars burning petrol, but it is still a waste of resources, time and energy.

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* for example, here’s a back-of-an-envelope type calculation: one paper I found suggested an average figure of 65~70,000 kg of CO2 equivalent emissions per lane, per kilometre to construct a limited access highway, so say there’s about 300 million grammes of CO2 per kilometre of a normal motorway-style road. If 20,000 vehicle journeys per day shift onto the new route, and each vehicle emits 3g/km less CO2 as a result of the better geometry, then in 14 years the new motorway will have repaid its construction emissions. The problem, as I said above, is what happens if the presence of the new road creates an overall increase in journey-kilometres, and thus higher emissions overall..

The thing with this CNRR is still fairly simple - if the M20 gets built (and even if it got watered down to 2+2, god help us) then you STILL need to link the N/M20 with the M8. You can't have freight destined for Limerick coming along the M28, along the N40, pottering through suburban Blackpool, then going north on the new N/M20.

That said, I worry about this scheme... it should have been bundled with the M20 for sanity reasons (albeit expensive) and basically fudge it by having the M20 start on the M8 at Glanmire.

I'd love to see a transport hub/interchange at that location too.

It's also expected to be the location of the new hospital in future.

The terrain here is not rail-friendly- the current lines both run in valleys, while the new road will run at a greater height. You could build a rail viaduct alongside the road, but you’d be left with a problem of how to get back down to the existing lines.

In general ,unless your talking huge huge volumes , or connectivity to an existing rail system is there anything rail could do better than a decent bus route ? ( If cost and terrain were no object ?)

The only reason people will willingly take public transport is if the city is full of traffic ,