Completing the motorway to motorway junctions on interurbans

Kermit.de.frog

Anyone know is this on the cards?

It would be fairly cheap and relatively small projects for the potential benefits.


For example you should surely be able to go to the M6 west bound from the M4 east bound. You should also be able to go from the M6 east bound to the M4 northbound on a flyover. Instead the flyovers to accommodate these movements are missing.

Same with M7/M9 and M7/M8.

Any chance of this coming on the radar?

Like I say reasonably cheap and would make a difference.

marno21

M4/M6 is possible using the two Kinnegad junctions on the M4/M6 (and is signed as such).

M7/M8 will not be happening anytime soon due to the toll and the presence of functional regional roads to accomodate the tiny amount of traffic that want to make such a move.

M7/M9 likely will not be happening any time soon, if there was a remote chance of it happening it would be included in the M7 upgrade.

Kermit.de.frog

I'm trying to think of any other country in Europe I have been to, or the United States, and I can not think of anywhere that would rely on regional road connect with roundabouts etc to make such a movement between highways.

Seems half assed to me.

Just build the junctions properly. Seems simple enough.

We should not be accepting second rate roads.

Look at the M17/M6 - we ignore best international practice and take a failed Brit design that to my knowledge is used no where else and implement it. Tells you all you need to know really. Would have been cheaper just to do it properly.

marno21

Kermit.de.frog wrote: »

I'm trying to think of any other country in Europe I have been to, or the United States, and I can not think of anywhere that would rely on regional road connect with roundabouts etc to make such a movement between highways.

Seems half assed to me.

Just build the junctions properly. Seems simple enough.

We should not be accepting second rate roads.

Look at the M17/M6 - we ignore best international practice and take a failed Brit design that to my knowledge is used no where else and implement it. Tells you all you need to know really. Would have been cheaper just to do it properly.

In relation to the M4/M6, M7/M8 and M7/M9 junctions, these are all roads between X and Dublin, they are simply multiplexing. The non-Dublin destinations of the M4 and M6 (N17), M7 and M8 (N20) and M7 and M9 (N24) are served by different roads.

M6/M17/M18 junction was designed as such to tack an MSA onto the junction, which later failed.

Kermit.de.frog

marno21 wrote: »

In relation to the M4/M6, M7/M8 and M7/M9 junctions, these are all roads between X and Dublin, they are simply multiplexing. The non-Dublin destinations of the M4 and M6 (N17), M7 and M8 (N20) and M7 and M9 (N24) are served by different roads.

M6/M17/M18 junction was designed as such to tack an MSA onto the junction, which later failed.

Look, you know it yourself, and you can make all the excuses you want.

Just build the junctions properly. These are motorway - motorway junctions. All connections should be catered for and freeflow between these junctions.

It's second rate and if we make excuses for it nothing will change.

AugustusMinimus

Junctions in Ireland are an after thought with anything complex involving a Roundabout. A joke.

plodder

Having used the M17/M6 junction a few times, a simple thing they could do with it, would be to reduce the roundabout to one lane and use the freed up space as merging lanes from the incoming roads. It always seems silly having to come to a complete stop on such a lightly trafficked junction.

Chris_5339762

The M8N to M7W and the M9N to M7W would be very easy to do... a simple little sliproad would do it. The M7E to M8S would be a bit more work, same for the M7E to M9S.

The M6/M4 actually works ok, it uses a regional road which isn't perfect but works... not a massive amount of traffic uses it.

But the M7/9 missing links you have to go through Kilcullen which is absolutely stupid and the M7/8 has you going through Rathdowney and the roads that way are awful.

prunudo

I posted a similar question on this forum a while back Kermit and I was given the same replies.
At the time I didn't realise there were alternative routes but as you say it still doesn't make it right.

Chris_5339762

The M7/8 junction was originally supposed to have two more junctions nearby (you'll notice there is no M8 J2) which would have linked up the missing movements similar to M4/6. But ABP rejected those junctions just incase they ever planned to make it all freeflow. And that probably won't happen anytime soon.

JupiterKid

Motorway fork junctions are quite commmonplace in other countries - the M1/M6 junction at Catthorpe in Britain was like this until the upgraded A14 from East Anglia was tacked onto it in a horrible substandard fashion and had to be eventually rebuilt....

But then again for traffic from Coventry to the M1 northbound there is the M69 to cater for that movement.

We don’t do motorway to motorway or DC junctions at all properly in this country. Just look at the mess with the M50 when originally done on the cheap and the main junctions had to be rebuilt free flow (granted, it was cleverly done given the space limitations). Look at the mess at Dunkettle.

The highly radial pattern of our motorway system means that the M7/M9 and M7/M8 forks won’t be made fully directional anytime soon. The old N6 (R446) connects the M6 to the M4 at Kinnegad. But I just don’t see traffic volumes wanting to make those types of movements warranting full directional anytime soon. Upgrading the regional roads that do cater for these movements might be a better solution.

IMO I have repeatedly stated that the M6/M17/18 junction is a travesty. Based on a failed UK 3 level roundabout stack design. This should have been a whirlpool or a Parclo.

But we have much more pressing priorities with our roads needs than rebuilding the aforementioned junctions. Like the M20 to start with!