Cork Southern Distributor Road [route selection]

AugustusMinimus

cantalach wrote: »

I reckon the all-new 190m section cutting through the Mangala Wood to join Grange Road (R851) to the old Carrigaline Road (R609) will be fought tooth and nail locally. Local teens will be badly affected as the wood is a favourite spot for a sess’...

Will have to be a bridge over the wood. Will relieve a huge amount of pressure in the area and give Grange and Donnybrook much sought after access to the M28. I might bumb an old thread on it.

marno21

cantalach wrote: »

I reckon the all-new 190m section cutting through the Mangala Wood to join Grange Road (R851) to the old Carrigaline Road (R609) will be fought tooth and nail locally. Local teens will be badly affected as the wood is a favourite spot for a sess’...

I think the proposal to widen the Rochestown Road for bus and cycle lanes will be even more entertaining when it’s published

AugustusMinimus

marno21 wrote: »

I think the proposal to widen the Rochestown Road for bus and cycle lanes will be even more entertaining when it’s published

Will the section just after the finger post be widened? This will require a lot of CPO and the demolition of some structures.

cantalach

AugustusMinimus wrote: »

Will the section just after the finger post be widened? This will require a lot of CPO and the demolition of some structures.

Some only very recently built. Lots of money on that stretch of road. The opposition will be unreal. That said, if you can widen Leopardstown Road in Dublin, you can widen anything.

marno21

AugustusMinimus wrote: »

Will the section just after the finger post be widened? This will require a lot of CPO and the demolition of some structures.

It’s unclear yet - but the high level map in the first post of this thread would indicate that the Southern Distributor will go from Douglas to the N28 presumably via the Rochestown Road. It’ll be a challenge no matter where it’s routed along there as we know from the M28

Treehelpplease

Theres also a humongous amount of massive trees all along one side of the rochestown road from the hotel to the finger post. On the other side are loads of houses. The majority of the road is really wide already at least i guess

hans aus dtschl

https://www.boards.ie/discussion/comment/114109915#Comment_114109915

This is nearly two years ago now! Does anyone know if anything progressed?

Jayuu

EDIT: Post moved to N40 upgrade thread.

Chris_5339762

They've already scrapped the Mangala wood bridge, which was probably the single most important part of this entire project. So I doubt anything actually useful will see the light of day here.

DylanQuestion

I've been putting some thought into this and I don't think the current plan of using the R610, R609 and R851 is the best of ideas. I think they should go for the path of least resistance here, which would be a new road entirely on the edge of the south city, like is planned for the Northern Distributor. Something like Monastery Road - Garryduff Road - Sciart Cross - Togher Road/Leghanmore Road - Spur Hill/Sarsfield Road - N40 J2. I think they're going to struggle a lot widening the R610 and R851 to make it effective as a multi modal distributor, esepcially as the bridge over Ballybrack Woods is going to be a huge hurdle for planning

hans aus dtschl

I understand your logic here, but I don't know if a distributor outside a bypass can work.

I'd love to underground the N40 like the Maastricht A2. The problem is that we already have flyovers at Douglas, KRR, and BRR so the cost of it would be astronomical. Right now I don't see a better solution than R610 and R851 unfortunately. It's why alternative transport modes are kinda urgent now. Probably need to toll the N40 then, and obviously badly need the Northern Bypass too.

DylanQuestion

I think closing N40 exits that are primarily/exclusively used for local traffic will prevent any issues of the distributor being outside. The R610 distributor will also be outside of it. I agree about the N40 being tunneled too, what a huge difference that would make!!

cantalach

https://www.boards.ie/discussion/comment/121605863#Comment_121605863

I don't know what "primarily/exclusively for local traffic" means and how you would determine which N40 exits (and presumably entrances) meet this criterion.

DylanQuestion

https://www.boards.ie/discussion/comment/121606643#Comment_121606643

Douglas (West) J7 on ramp, Bloomfield J9 on ramp, Maryborough Hill on ramp, one or both of the Douglas off ramps and Curaheen J2

Hibernicis

https://www.boards.ie/discussion/comment/121602215#Comment_121602215

Your red line is actually an outer bypass and would largely function as such, with the N40 continuing to act as an inner distributor. (e.g. general traffic from say the CC to Douglas will hardly drive to the airport, across to the Coach Hill/Rochestown Road junction and back into Douglas, it will continue to use the N40). Changing the N40's role will be very difficult given the number of traffic magnets (Mahon Point, the Douglas shopping centres, Dunne's Bishopstown and the numerous Retail Parks (pseudo industrial estate complexes) that have been given permission over the years and that use the N40 as their primary access. It's very difficult to determine what the optimal solution is at this late stage. Certainly completing the Northern Distributor and the N40 North and West (completing the N40 Orbital) would alleviate pressure on the South side. An alternative, based on your drawing, would be to link the N40 at Jacobs Island to your Red Line somewhere around the Rochestown Inn, and classify your Redline as the N40 and allow it to act as a bypass, and reclassify the remaining N40 (Mahon Point to Bishopstown/Ballincollig) as the distributor road. The topography and settlement patterns of red line are another question altogether. As I said it's going to be very difficult to engineer a good solution, especially in the current anti-roads environment.

cantalach

https://www.boards.ie/discussion/comment/121606963#Comment_121606963

Closing the Bloomfield and Douglas on-ramps would obviously make it harder for anyone in the wider Douglas area to access the road. But wouldn’t that just have the effect of massively increasing traffic on Well Rd, Skehard Rd, Rochestown Rd, Grange Rd, South Douglas Rd, Turners Cross, Old Kinsale Road, etc., etc.?

Pete_Cavan

The following is a suggestion for the Cork Southern Distributor Road, essentially it takes over the N40 between the Kinsale Road and Bandon Road junctions. Between these junctions a new N40 route is built south of the existing development.

The SDR is the red line. The existing N40 between the Kinsale Road and Bandon Road junctions gets redeveloped with a general traffic land in both directions, a bus lane in both directions and segregated cycle/walking facilities along the route. It would extend east on the northern edge of the existing N40 as far as South Douglas Road, to facilitate this, the N40 would be reduced to two eastbound lanes and the J7 off ramp removed. Ideally the next off ramp as well as the westbound on ramp would also close but I don't think that will fly.

It all gets very tight on approach to South Douglas Road. An alternative would be the SDR switches from the northern side to the southern side of the existing N40 at Kinsale Road, meaning it could tie into Douglas Link Road. Or the SDR could be either side of the N40, eastbound to the north and westbound to the south. This would mean the on ramp at Douglas would definitely have to be removed.

On the northern side of the SDR, a Luas line is created from Wilton to Kinsale Road, the purple line in the image. It continues north on the South Link Road which is reduced to two lanes, one in each direction. The Wilton and Kinsale Road junctions, as well as the two overbridges, would be redeveloped as interchanges with feeder buses, junctions for cars would be signalised (with right turns), Luas given priority and pedestrian/cycle access greatly improved. A separate branch goes south to the airport and P&R at new N27 junction. I don't know if the existing Cork Luas proposal is realistic, it goes through very developed areas and there seems to be a lot of objections (even from Cork City Council). If it doesn't happen, my proposed Luas route could use the current identified route west of CUH and east along Centre Park Road.

A new N40 is built between the Kinsale Road and Bandon Road junctions. At both those junctions, it uses the existing elevated sections which are altered to turn south. The existing junctions become part of the SDR with new N40 junctions built further south with links to the N27/N71. This reduces the number of junctions on the N40 and allows it to function better as a long distance route linking mainly N roads.

Chris_5339762

An interesting idea that would improve airport access and N71 access.

Nice as it would be, it does nothing for the N28 to N27 section across Douglas, which is where the problems are.

hans aus dtschl

https://www.boards.ie/discussion/comment/121628032#Comment_121628032

A lot to like about this.

I'd even consider routing further south of the Bandon Road Roundabout too.

hans aus dtschl

https://www.boards.ie/discussion/comment/121629325#Comment_121629325

Yeah but even if it's not absolutely perfect it's still the best overall plan I've seen.

Pete_Cavan

https://www.boards.ie/discussion/comment/121629325#Comment_121629325

Well it would remove from the N40 traffic from the general Douglas area looking to get to places between Douglas and the N71. That traffic would either use the SDR or, ideally, switch to public transport. It would also discourage people from using the N40 and South Link Road to get to the city centre.

The only way to address the N28 to N27 section is to get some of that traffic off the road. The only way to do that is to provide a distributor road with proper public transport and have the N40 as a bypass. Ideally the SDR as I proposed would extend further west but there just isn't any suitable space. I don't think there are any perfect solutions to be had here but I think the above is as good as it gets.

Pete_Cavan

https://www.boards.ie/discussion/comment/121629393#Comment_121629393

I did think about the new N40 conticontinuing south of the Bandon Road Roundabout too but I don't think it is worth it. The existing N40 west of the N71 is good, there is no point in replicating it further south, the costs would outweigh the benefits.

DylanQuestion

https://www.boards.ie/discussion/comment/121630006#Comment_121630006

The worst thing about removing the N40 as access to the city centre for the southside is that Bus Connects is advocating that people in Douglas and surrounds use the N40 and N27 instead of Douglas Road! It makes no sense to me

snotboogie

I’d run the Luas East and then South to Carrigaline (and possibly Ringaskiddy) on the current N28 rather than South by the N27 to the Airport. There is a very difficult build around Douglas but get you access to Douglas Village and current big population and development centres in Maryborough and Carrigaline and the gradient going South is much smoother on this corridor. You still have the option of a spur to the airport further down the line if it keeps growing. You also have an option to tie into a potential commuter rail bridge from Great Island to Glenbrook or Monkstown which could be run south to create an interchange station just north of Carrigaline which could be zoned for dense development. You then tie in massive areas of traditionally disparate residential and commercial activity throughout the harbour areas with a public transport network.

KrisW1001

I recommend using a map with contour lines as a base layer for these drawings.. there's some really nasty gradients along that route, which would need a lot of cutting or bridging to bring within the specification for a new road build.

Limerick74

A series of park and rides at every junction on N40, with loads of buses and toll the N40. Seems crazy to be considering a bypass of the bypass these days. Northern distributor road more essential imho.

Pete_Cavan

https://www.boards.ie/discussion/comment/121636018#Comment_121636018

No doubt it would be a difficult and expensive build, probably involving tunnelled sections. I'd still see it as the most realistic option which would make an actual difference. The idea of creating a suitable SDR out of existing residential roads simply isn't realistic, just look at Cork BusConnects.

The official proposal and image in the first post on this thread seems to indicate a new section of road in that area anyway, just as SDR rather than N40. If that new section of SDR is to have general traffic lanes, bus lanes and public/active transport provision, it would be as wide as a new N40 with all the same engineering challenges so would be just as expensive.

My proposal creates a high quality SDR which could effectively function as a distributor road to relieve the N40 of that function. It also major provision for public and active transport without having to CPO at all. It requires a relatively short offline new build, albeit the cost per km would be very high. The only realistic alternative that I can see is to do nothing.