Why is there no link to travel west along M7 where it meets with M8

deaglan1

I naively assumed that when two motorways come near to one another, there would be options to join one to the other in both directions. Travelling from Kilkenny I joined the M8 and I planned to cross to M7 and head westwards towards Roscrea. Instead I ended up seamlessly joining the M7 eastwards bound and having to travel to Portlaoise plus a toll booth before being able to get back on course. What seems such an obvious joining point to connect these two motorways to allow movement in any direction just isn't there. Why? The M6/M4 provide it at Kinnegad. The M6/M17/M18 provide it at Athenry.

brianc89

https://www.boards.ie/discussion/2058310042/why-is-there-no-link-to-travel-west-along-m7-where-it-meets-with-m8

I made the same mistake years ago though from the other direction. The seemingly total lack of logic really bothered me and I never understood why.

EchoIndia

Presumably, when designed, the focus was primarily on linking the M8 catchment and Dublin, though traffic volumes then were probably a good deal lower than now. Ultimately every additional element incorporated would have involved extra land purchase, design and construction costs; as always, adding extra roads and junctions many years after the event would cost even more. 😮

icdg

It is the exact same at the M7/M9 junction (and indeed, despite what an earlier post said, at the M4/M6 albeit there are other junctions sufficiently close for it not to be as big an issue).

Yes basically the thinking was this is the Dublin/Cork road, because anyone travelling Cork/Limerick would be using the N20 right? (Obviously not taking into account people join and exit the motorway from places other than it’s terminals).

loyatemu

I think it was considered the numbers making that connection were too small to justify the extra cost of a full junction, and the time saving vs coming off at an earlier junction and going across country for 20km would be minimal.

M8-J3 to M7-J21 is 18 mins drive via Rathdowney according to Google. It would take about 8 mins @ 120km/h if there was a full M7/8 junction, I guess they didn't consider a 10 minute saving for a small amount of traffic worth the extra cost.

realdanbreen

https://www.boards.ie/discussion/2058310042/why-is-there-no-link-to-travel-west-along-m7-where-it-meets-with-m8

Seriously, you set off along the motorway heading for Roscrea without first checking the map! And you (hehe) ended up in Portlaoise then had to pay a toll to get back down to Roscrea! TBH it's a bit like the lady in the states who sued the microwave supplier because there wasn't a label on it telling her NOT to dry her little dog in the microwave!

deaglan1

https://www.boards.ie/discussion/comment/121007789#Comment_121007789

Yes, I seriously thought that all motorways would provide connectivity in all directions at or near their point of contact...the idea being that it would serve those of us who do not commute between city A & city B but would still like to avail of using motorways to expedite our journeys in comfort and with greater safety than having to rely solely on the use of twisty narrow roads. And yes, travelling from Kilkenny to get to Roscrea, the detailed hardcopy map that I looked at left an impression that using portions of both motorways was a viable option. Ain't I just the complete moron for considering this to be common sense? You are so bright.

realdanbreen

https://www.boards.ie/discussion/comment/121013972#Comment_121013972

Well I'm certainly bright enough to NOT turn a 60km spin from Kilkenny to Roscrea into something like the Dakar car rally with Tolls!

road_high

I think full junction options on the M8 and M9 to M7 would be extremely useful indeed to the network for not a lot of money and add a lot in terms of road safety.

Seth Brundle

https://www.boards.ie/discussion/comment/121031790#Comment_121031790

Is there evidence that shows there has been an issue in terms of road safety with the current layout?

EchoIndia

https://www.boards.ie/discussion/comment/121031790#Comment_121031790

How much would it cost?

dublincc2

This is the reason there is no J20 on the M7 or J2 on the M8. I believe the plan was to build a west-south link with these junctions but because of the crash it was flushed away down the toilet. Not sure if it will ever be completed now.

road_high

https://www.boards.ie/discussion/comment/121031991#Comment_121031991

None at all but regional roads have statistically higher accident rates than motorways so taking traffic off them would be a road safety plus

Seth Brundle

https://www.boards.ie/discussion/comment/121032107#Comment_121032107

Big assumption being made there so. That's not how they would carry out a cost/benefit analysis on the need for a new junction layout on safety grounds.

road_high

https://www.boards.ie/discussion/comment/121032604#Comment_121032604

I feel you’re looking for an argument for the sake of one so I’ll leave you to it. I’m not a road engineer but I’ve no doubt both junctions would be widely beneficial and make maximum use of the sunk costs already invested in the three motorways. Any stats prove motorways are safer than single carriageway R or N roads

Seth Brundle

https://www.boards.ie/discussion/comment/121033252#Comment_121033252

I'm just challenging your unproven claim that a new junction would "add a lot in terms of road safety"