N4 - Dromod/Roosky Bypass

JupiterKid wrote: »

The N4 Roosky-Dromod bypass was opened a few days ago. It was originally supposed to be a 2+1 road, but it was decided during constructiuon to make it a 2+2 - effectively a dual carriageway.

But surely if it was only planned to be a 2+1, the bypass must have no hard shoulders? I've heard that the divider between the carriageways is only a wire rope fence. This seems very substandard for a road that claims to function as a dualler.

Just to point out the Dromod -Roosky Bypass was originally intendened to be a Wide Single. The traffic flows on this section would never justify a Standard Dual.

Duzzie

1. One would be tempted to put a jersey barrier in the middle. It would fit, but it would be awfully tight. Are cyclists expected to use the "hard shoulder"?
2. It is interesting that the signs merit Armco barriers, when there are collapsible signs on the market. It is very interesting that the Armco barriers continue afer the sign.
3. Sightline doesn't look great. Is there an underpass here?
4. Armco barrier fitted in the wrong place - if vehicles go up the embankment, they can still hit the underside of the bridge. Barriers are much more important before a bridge than after.
5. Again, sightline doesn't look great.

Chris_533976 wrote: »

What I'd do is reclassify the HQDCs to motorway, and have these labelled N with similar status as the DC bits of British A1 or something like that, with 100kmh limits.

They cant be motorway restricted, as they have roundabouts for junctions. Thats the thing.

you could have something similar to the French "motor vehicles only" restriction that applies on many of their dual-carriageways (and some single-carriageways)

murphaph wrote: »

Only if they are signed with a otherwise they are signed as 60. Much of the A1 in NI is indeed 60, even the DC bits as it's quite twisty.

Well, in fact it's more the other way around. A Dual Carriageway in the UK has a 70mph limit unless a lower limit is posted. And yes, the sections of A1 around Banbridge and Dromore have 60 limits. These have more to do with median crossings than curves. The Newry-Beech Hill section is curvy, though, and has a 60 limit because of this.

munchkin_utd wrote: »

they also seem to be focusing on the N16, probably the least trafficed national primary route, and that it doesn't have a hard shoulder for planned upgraded sections , even though the traffic doesnt justify it.

with the logic that you build way beyond whats needed especially when you're not paying for it, sure why not push to build a full motorway to Enniskillen. Sure they are the safest roads arent they?

O.T but... That road is under utilised because of its crappiness in my opinion. Road to the second biggest city should definitely get an upgrade. I think it would increase usage a huge amount, not to mention increase Sligos attractiveness for investment,

marno21 wrote: »

If you have a breakdown on the 98% of Irish roads without a shoulder you have the same issue.

2+2 functions well for a variety of reasons.

1. Breakdowns these days are rare. People should also maintain and check their tyres and cars to make breakdowns less common. Hard shoulders were an idea from an era of very unreliable cars.
2. The hard shoulder on a WS2 road is 5-6m of fully paved road that is rarely used except for people pulling in to overtake. The 2+2 design is more efficient with use of available tarmacadam.
3. There is a roundabout in the middle of the Dromod/Roosky bypass, and you can't travel far before being able to get off it.
4. Future 2+2 schemes with long distances between exits such as the N4 in Sligo will have emergency laybys every 2.5km or so. You'll never be more than 90 seconds from a layby at the speed limit.

If there's no nearby alternative routes between the towns and villages, and residential access is still provided for, then the 2+2 doesn't allow for any kind of sane pedestrian or cycling use. It would be reckless to even walk to the neighbour's house.

The contrast with a typical Irish road is that bends and limited visibility and indeed congestion and established driver behaviour when driving alongside a ditch, all these things make a single pedestrian or cyclist less of a sudden and nasty surprise.

The presence of a second lane completely changes driver attitude into one where overtaking, and therefore max (hopefully at the limit) speed, is effortless.

Road designs like that need to have space for those going at far lower speeds. For instance, the NRA were forced to close most of the climbing lane on the now R132 in Louth precisely because a stationary car was rear-ended in the non-climbing lane, while waiting to make a right turn. It resulted in the deaths of the occupants of the car.