Exit numbers on the M4

BrianD

Drove to Kilcock today. I notice that the exit numbers jump from 4 at Maynooth to 8 for Kilcock. Are they going to renumber the exits back to the M50 or should we expect another 4 exits between Maynooth and Kilcock???

murphaph

I reckon a renumbering is on the cards, J1 will be M50, J2 Fonthill Rd, J3 Woodies, J4 Newcastle Rd (when it's grade separated), J5 Spa Hotel, J6 Celbridge Interchange, J7 Maynooth, J8 Kilcock...or soemthing like that

icdg

Makes sense, though I'm not sure non-motorway sections should have numbers...

At least it will get rid of the fact that we have a "Junction 2a" (Celbridge) on such a short route!

Jamax

Hi,

I think no renumbering will be done for this.

This motorway uses the Spanish standard in numbering exits in motorways. In this system the exit number is the km at which the exit is in.

The motorway has a start point which is set as 0km. Then Exit 4 at Maynooth, is numbered like that because the exit is at 4km from the start point, Exit 8 for Kilcock is at 8km, etc.

With this system there is no need to renumbering or adding exits like Exit 3A, 3B, 3C etc. If in the future another exit is added between Exit 4 and Exit 8, let's say at km 6 it will be called Exit 6. Otherwise if the exits were labeled 1,2,3,4... then you will need either relabeling or add a 2A style exit.

dowlingm

Ontario uses the kilometre = exit no. system too. It's a very good idea.

dowlingm

Ontario uses the kilometre = exit no. system too. It's a very good idea.

Andrew Duffy

Nice theory, but the junctions for Maynooth and Kilcock are not 4 and 8 km from the start of the M4 - they are 7.8 and ~16 respectively, according to the router planner at aaroadwatch.ie.

spacetweek

Jamax wrote:

This motorway uses the Spanish standard in numbering exits in motorways. In this system the exit number is the km at which the exit is in.

Many countries have this system (not just Spain), and it is a very good idea. However it is probably only worthwhile on long stretches of motorway. Maybe the M4 is a bit short for this.

icdg wrote:

Makes sense, though I'm not sure non-motorway sections should have numbers...

Don't see why not, it's better for it to be coherent. In a country like Ireland nearly all motorway journeys involve some dual carraigeway aswell. Wonder if they'll continue the M4 numbers on the new N6? It's all part of the same route to Galway after all. This numbering should be extended to the N7, N8 and N9 too, when they're complete.

icdg

Jamax wrote:

Hi,

I think no renumbering will be done for this.

This motorway uses the Spanish standard in numbering exits in motorways. In this system the exit number is the km at which the exit is in.

The motorway has a start point which is set as 0km. Then Exit 4 at Maynooth, is numbered like that because the exit is at 4km from the start point, Exit 8 for Kilcock is at 8km, etc.

Nope - its numbered sequentially just like every other Irish motorway (that has numbers, that is)- the junctions are numbered 2, 2a, 3, 8, 9, 10, and 11 - with the junction numbering continuing on the N4 Mullingar Bypass. Maynooth is actually Junction 3, not 4. The problem is the gap between J3 and J8, when there's nothing particularly big worth building a junction for in between, let alone four junctions.

The numbering is already continued for the remaining dual section of the N4 (not counting the bit in Sligo). I would presume the half-completed diamond would by N6 Junction 2, not 12 - but I could be wrong in this regard. Likewise the M9 Kilcullen Junction should be J2, not J10, but given J7-J9 has been proclaimed the M7 (M9), I wouldn't be on it.#

The M1 is being given junction nos BTW - I saw the airport has been branded as "Junction 2" recently (despite the fact that Santry should probably have been given that number - but that's another argument involving whether Santry will be part of the M1 at all soon...)

lostcarpark

The "join the dots" school of motorway building we practice in this country can make it difficult to assign junction numbers, since we have many seperate pieces of motorway with a vague intention to fill in the gaps some day. I think it would have made sense to backtrack numbers to a logical starting point, even if that starting point isn't actually motorway. Someday, it might be upgraded, and even if it isn't, it doesn't do any harm to number the junctions on the N road.

The M50 could probably have made "Junction 1" where the N32 meets the Malahide Road. You could backtrack the M7 numbers to the Canal, and you could number M4 junctions from Heuston.

I'm glad to see the M1 is finally getting junction numbers, but they should have been there three years ago when we had continuous motorway from Santry to Dundalk. I think at the very least the numbering should start at Whitehall, but if you were being progressive, you'd put J1 on Dorset Street.

I presume J1 has been put at the M50 roundabout, and the section from there to the Port Tunnel (and the tunnel itself) will be considered part of the M50.

darkman2

I know its a bit off topic but can anyone tell me whether the Port Tunnel itself will be:

a: 'N1' road
b: 'M1' motorway
c: 'M50'????


The actual layout of the tunnel does not allow for a proper hard shoulder (the result when things are built too small) so in my view it cant be motorway and the planners are to blame:mad:

icdg

Apparently "M50" is its designation. Even if it doesn't have hard shoulders, if Motorway Regulations are applied to the route it is still a motorway - we do have in fact one single carrigeway motorway already which is the M1 (as is currently, that is) between Whitehall and Santry. No hard shoulder and indeed no central median. Still a motorway, as the Motorway Regulations apply to traffic on it. There's apparently an A6144(M) in England which is a single carrigeway motorway too...

lostcarpark

I presume once the port tunnel opens, the'll put up "end of motorway" signs and redesignate the section to Whitehall as R-something-or-other.

icdg

Santry to Whitehall maybe, they can revoke the motorway order for . But from Santry on there's no access to a non-motorway route until the N32. That meants that after the Santry junction they need motorway restrictions. (The same reason for the existance of the one-way M6 in Westmeath...)

BrianD

icdg wrote:

Apparently "M50" is its designation. Even if it doesn't have hard shoulders, if Motorway Regulations are applied to the route it is still a motorway - we do have in fact one single carrigeway motorway already which is the M1 (as is currently, that is) between Whitehall and Santry. No hard shoulder and indeed no central median. Still a motorway, as the Motorway Regulations apply to traffic on it. There's apparently an A6144(M) in England which is a single carrigeway motorway too...

How can it be the M50? The M1 maybe.

murphaph

BrianD wrote:

How can it be the M50? The M1 maybe.

M50 is more likely from what I hear. The M1 junction numbering also seems to support this as the M1 airport junction was recently given a number '2' on it's fork sign. That would imply the M50/M1 junction at Turnapin would be juncton 1 on the M1. It makes perfect sense to designate the port tunnel as M50 when you consider the long term 'plan' involves further tunneling and to complete the Dublin Orbital Motorway, so if it was M1 the orbital motorway would have 2 numbers and that would be pretty odd. I believe 'M50' also appeared on some early port tunnel documents.

M50, M1 M7 etc. have NO legal meaning in irish law. Motorways are created differently here than in the UK where the number means something. Legally the entire road from O'Connell Bridge to the border with Northern Ireland is N1, regardless of whether or not you're on a motorway section of it. Similarly the M50 is legally the N50. You will not find the M50 in any descriptions in the roads act-only the Declaration of Roads (National) and Declaration of Roads (Regional) will be found.

It's actually legally easier in theory to make a road a motorway in Ireland, the problem is compensation for affected landowners who suffer permanent loss of access when the motorway (protected road) order is signed by the Minister. It's just a statutory instrument like any other but the law guarantees land owners compensation when a road is made protected. In theory a road could be a 'half motorway' ie, no pedestrians/cyclists but tractors permitted. That would be possible under our law.

BrianD

Well I wouldn't rely on the NRA to either create legal signage or designate exit numbers. However, your reasoning makes sense. Is the existing M1/M50 in the upgrade plan so there is a free flow situation for the current M1 (soon to be M50) onto the existing M50 (soon to be a truck park)?

jmkennedyie

Hey BrianD,
Back to your original question: maybe you hit the nail on the head about 4 junctions between Maynooth and Kilkock...ever heard of the Outer Orbital Route? I understand NRA are currently funded to investigate potential route of a new Motorway from Drogheda/Dundalk to Navan to Kilkock/Maynooth to Naas/Newbridge and possibly beyond (i.e. to the Wicklow Coast!).

That could consume some of the numbers from J4 to J8 on the M4.

PS. Anyone have any update from NRA on this project?

murphaph

BrianD wrote:

Well I wouldn't rely on the NRA to either create legal signage or designate exit numbers.

Nor would I to tell you the truth. They have received complaints from me recently about this.

BrianD wrote:

Is the existing M1/M50 in the upgrade plan so there is a free flow situation for the current M1 (soon to be M50) onto the existing M50 (soon to be a truck park)?

Yep, fully freeflowing movements provided for between M1 and M50 in all directions. The N32 will still use the roundabout (presumably remaining signal controlled to ensure traffic doesn't back up down the M1 and M50 approaches).

MT

Does anyone know if variable message signs are being erected before or either in the tunnel - pic from Australia?

As it's a major freight route connecting directly to a port these might be useful to inform truck drivers of delays, congestion or accidents ahead. Particularly on the Northbound carriage as there could be delays at the M1/M50 junction.

jmkennedyie

A complicated looking gantry has been erected just before the N1 entrance into the tunnel. Presumably it will have variable message signs, although whether they are LED based or just regular signs that have a couple of messages that can rotate, I don't know.

murphaph

There are also 2 new led based VMS displays southbound on the M1 before the airport exit and before the M50. What does the new one just before the tunnel portals look like?

Victor

icdg wrote:

The M1 is being given junction nos BTW - I saw the airport has been branded as "Junction 2" recently (despite the fact that Santry should probably have been given that number - but that's another argument involving whether Santry will be part of the M1 at all soon...)

Coolock Lane is already Junction 2on the M50