M50

Pataman

This may have been asked before but why is the section of the M50 at Tallaght to Ballinteer 60mph?

Victor

Because

(a) it has twists and turns - lower visability and harder handling.
(b) it is elevated - more prone to frost and ice.
(c) it is the end of the motorway.
(d) I don't think it has a central crash barrier.
(e) it was probably designed for that speed.

Why do you ask?

Andrew Duffy

I think it does have a central barrier - doesn't that section have a very narrow median and a some fairly big height differences between the carriageways? Anyway, 60 mph is quite high for an urban motorway, especially towards a construction site. It may well go up once the Sandyford interchange is opened, which I believe will happen soon despite the trouble at Carrickmines.

Saruman

Nope none of those reasons are correct. I was told by someone who lives in the area that the residents demanded a lower speed limit to cut down on traffic noise. If you notice there are houses etc all around that area unlike most of the rest of the motorway. Nothing to do with twists and turns etc as there are only slight twists and none dangerous.Oh one other possible reason is at the sandyford end there are deer there and there is a warning sign as they can possibly jump the fence.

a_ominous

Originally posted by Saruman
Nope none of those reasons are correct. I was told by someone who lives in the area that the residents demanded a lower speed limit to cut down on traffic noise. If you notice there are houses etc all around that area unlike most of the rest of the motorway. ..

Then why build the houses so close to the motorway? IIRC the route was a greenfield site. I've seen new apartment blocks going up beside the motorway. If you don't want traffic noise in your house, don't buy a house beside a main road.
Also the M50 near Mad Cow roundabout was built _after_ houses in Woodford / Dutch Village. And some of these are just over the wall of the north bound carriageway.

Having said that, I'd agree with you. The southsiders probably know more influential people to get the speed limit reduced. So the question stands, why spend hundreds of millions of public cash on a dual carriageway???

Pataman

Originally posted by Victor
Because

(a) it has twists and turns - lower visability and harder handling.
(b) it is elevated - more prone to frost and ice.
(c) it is the end of the motorway.
(d) I don't think it has a central crash barrier.
(e) it was probably designed for that speed.

Why do you ask?

Just curious. I asked the NRA but never got an answer. Most people dont obey the limit( I know most dont obey limits anywhere), but I just wanted to know why a new motorway would be 60 not 70mph

robbie1876

I've heard yet another reason, this one was from Eoin Keegan talking on Newstalk 106 some time ago. He said that the speed limit would increase to 70mph once the motorway is finished. He said the stretch from Tallaght to Shankhill was commissioned as one project, so they can't put the 70mph limit in place because the stretch from Tallaght to Ballinteer is not officially a motorway yet, and won't be until the rest of it opened.

Don't know who to believe now!

Victor

I seriously doubt that, especially seeing as it's outside the city council area and outside his remit.

I would also doubt it would have blue signs if it wasn't a motorway.

robbie1876

it's outside the city council area and outside his remit

Good point. Still though, he must have had something to base his statement on. I can't imagine it would be a problem to put the blue signs up now, before the motorway is 'official'. It would be a waste of money to put other colour signs up and change them to blue later.

Plus, on all the approach roads to the M50 from Tallaght to Ballinteer, it says 'M50', not 'N50'. Overall, I think Mr Keegan was talking through his preverbial.

Pataman

It worries me that they are still using chickenwire and shrubbery to protect oncoming cars from each other. Most other countries I have been in have whopping great lumps of concrete.

Victor

Originally posted by Pataman
It worries me that they are still using chickenwire and shrubbery to protect oncoming cars from each other. Most other countries I have been in have whopping great lumps of concrete.

They aren't. I suggest you search boards.ie for "chickenwire" and read the recent responses.

DrEvil

i thought i was mainly a saftey issue due to the winding road and the strong crosswinds coming down from the mountians

BrianD

Chicken wire and hedges are not used as protective barriers any where in Ireland. Up to recently, the width of the median was deemed sufficient to not require a median barrier. In the UK, where the carraigeways are very close together, armco barriers are used. In Portugal, they have bloody great dykes instead of an impact barrier.


The reason why the M50 south of tallagh is so meandering is down to very unusual planning decisions. Certain individuals lobbied hard to divert the m-way away from them and others got the road right down the middle of their holding. Of course, numerous spurious exits (Carrickmines being the most notable) are also being constructed on the final section of the M50 that will turn into a local commuter road rather than a national primary bypass route as it should be.

Victor

Originally posted by BrianD
The reason why the M50 south of tallagh is so meandering is down to very unusual planning decisions.

There is also the matter of several hills and valleys, especially on the Knocklyon-Ballinteer section.

BrianD

No doubt there would be given the elevation and location. the big question is did it have to follow this route?

Bee

Because of the sub standard road surface material used on that stretch of road it is not capable of conveying cars travelling at motor way speeds!

Brown paper bags and all of that!

Perhaps I am only joking

Bee