N22 - Macroom to Ballyvourney (Macroom Bypass) [under construction]

Mrs Dempsey

Perhaps it was previously discussed but it looks like the Milstreet junction has off slips but no on slips (acceleration lane). I'm unaware of any similar DC junctions - what's the background on this?

KrisW1001

Yes, none of the junctions have on-slips. This is what the “Compact” in Compact Grade-Separated Junction means (the next step up is called “left-in, left-out” or LILO, and that does have acceleration lanes). There’s around 150 m of deceleration lane coming up to each exit, but it’s a straight left-turn for joiners.

But in fairness, this road is not a motorway; it’s a 100km/h main road and the traffic levels are low by motorway standards. If you want to join, you wait until there’s enough space for you get on and accelerate - it won’t take long. Also, the junctions are very visible, so people already on the road can pull over into the passing lane when they see traffic joining.

marno21

The junctions on the N4 and N5 Type 2 schemes are the same.

To a lay man they may seem dangerous but there’s more than enough spare capacity on these roads for the left lane to be used as a merging lane and a breakdown lane if needed. As Kris pointed out the road is 100km/h too not a full blown motorway

niloc1951

Traveling eastbound this afternoon a car entered from the R582 and seemed to misjudge my approaching speed. I was traveling at about 80km/h in lane one, faster traffic was overtaking me in lane two and I had no option but to hit the brakes. Unfortunately, he/she was one of the types that pull out and then don't accelerate briskly away, easing up on the juice would have done me if he/she did put the boot down a bit.

No acceleration/merging lane to join a rural DC with a 100km/h speed limit is a BAD idea.

road_high

https://www.boards.ie/discussion/comment/119984397#Comment_119984397

Unfortunately this is what can happen. Many motorists aren’t able to properly enter a motorway never mind one of these. They’re completely oblivious to all around them. Ideally they should add an acceleration lane

KrisW1001

Or to put it another way, a bad driver made a not very smart manoeuvre to join the road but the car behind still had plenty of time to see it happening and react. Sounds like the design is fine to me.

No road design is immune to stupid diving. I have seen people sail straight into the left lane on motorways at well below the prevailing traffic speed, rather than use the accelerating lane. Coming up to any junction, expect stupidity and you'll be grand.

And as there are only three intermediate junctions on this road, it's not like you'll have to be constantly watching out...

Pete_Cavan

The issue really is the standard of driving rather than the standard of the road. I have seen on motorways, people drive to the end the accelerating lane and think they are entitled to immediately pull over into the driving lane at well below the speed of traffic already there. They seem to think that they have to go to the end of the accelerating lane and then they have right of way, looking for an opportunity to merge or joining before the end of the accelerating lane doesn't seem to occur to them. Accelerating lanes don't prevent bad driving.

I don't know how much attention is given to using these types of junctions in driver training (there was none when I learned to drive and that wasn't all that long ago) but some is certainly required.

gooseman12

I know it doesn't make a blind bit of a difference to most road users, but are the signs on the entry lanes onto the road showing stop or yield?

veryangryman

I like the way the thread title still says "under construction"

It gives one hope for improvement on the work done

KrisW1001

https://www.boards.ie/discussion/comment/119986765#Comment_119986765

The design standard says STOP.

And the road says STOP too... three ways:

(N22 Westbound, Millstreet Road junction)

KrisW1001

https://www.boards.ie/discussion/comment/119987707#Comment_119987707

It says "under construction" because the project is still under construction. The completed road will run from East of Macroom to west of Baile Bhúirne and the western half is not open yet.

There is no need for improvement on the work done. A bit of improvement in driving standards, though...

AugustusMinimus

Bypass now showing on Google maps.

thomas385

https://www.boards.ie/discussion/comment/120000374#Comment_120000374

I'd imagine they will have it fixed (relatively!) soon. The same thing happened with the Castlebaldwin N4 bypass, but was fixed after a few months

murphaph

Adding a merge lane would only make things worse and confer on these idiots who just pull out a "right of way" that only exists in their heads. If a full stop junction doesn't force them to respect free flowing traffic on the main road, a short (or even longer) merge lane will only reinforce their ignorance. These people are bad drivers and probably do the same at every junction. It's not practical to engineer out their stupidity from the roads network. They need to be caught and prosecuted really.

I am pretty sure this junction design is actually safer than one with short merge (barge in) lanes. The AADT on these roads is sufficiently low that you will not have to wait long for a gap in traffic and as people get used to driving on them, they will attempt to move over to let traffic merge more easily. These roads are far superior to the ones built in most countries for such low traffic volumes.

Chris_5339762

That is true, there is pretty much no country on the planet that would build a dual carriageway thesedays for the amount of traffic that uses them. That said, there is pretty much no western country where the dual carriageway is replacing a road that is so poor.

I do think they made a very good decision though - a 2+1 or a good single carriageway would do the job. They used to say a 2+2 is 10% more expensive to build for not much more land take, and sticking to these for work like the N22 is an extremely good move.

KrisW1001

Sweden builds dual carriageways in places with similarly low traffic levels. The centre divide is for safety, not capacity.

This isn't a very busy road, it has a reasonably high share of goods vehicles and tractors, which would increase collision risks from overtaking if it was left as a single carriageway.

I suppose this would have originally been considered as 2+1, but the pilot 2+1 schemes showed that doing this road type the right way wasn't going to be much cheaper than doing a 2+2, and the 2+2 type was significantly safer as it didn't create pent-up demand for overtaking on the one-lane sections.

2+1 has been retired, and there will be no new ones.

dontmindme

https://www.boards.ie/discussion/comment/119987843#Comment_119987843

Should there not be a broken line inside that stop line?

serfboard

https://www.boards.ie/discussion/comment/120002214#Comment_120002214

As you say people like that behave like this on other junctions. I've often seen drivers pull out onto the hard shoulder of two-lane roads and treat it as a merge lane - often without seeming even to look.

My solution? A ruddy great speed bump just before the junction - you know one of those lethal ones that makes you come to an almost complete stop.

And to people who say that we shouldn't have to counter bad driving behaviour - we do this all the time. That's why we have drink-drive and speed limits. I'd rather counter the bad behaviour than end up with a horrific crash.

murphaph

I think a severe speed bump at stop lines is a really good idea to enforce coming to a complete stop. In fact we already have them, kind of. At traffic calmed junctions with pavements and cycle lanes continuing through the junction at the same grade, vehicular traffic is faced effectively, with a massive speed bump. The concept could be employed here too, just without the pedestrian/cyclist facility.

Having said that, we overuse the stop line in Ireland. In this case I think it's entirely justified but most cases could be handled with a yield sign but we force traffic to a stop where it's not necessary. Sadly people then treat all stop signs with less respect than they command in countries where they are used more sparingly.

lawrencesummers

https://www.boards.ie/discussion/comment/120002214#Comment_120002214

I dont agree, the line of sight for people is poor at that stop sign, anybody with eyesight issues, or health issues makes that line of sight worse, entering a road which traffic is traveling at 100km from a standing start is asking for trouble.

A merge lane, where some drivers dont know how to merge in or allow people to merge in has its problems as well but at least cars are not entering from a standing start and the traffic on the road has more visibility of them, you can read their intentions and hopefully see a clear indicator flashing.

Time will tell i suppose and road design has come a long way, but entering a road at an angle from a standing start with traffic driving at 100km is a terrible idea i think.

niloc1951

https://www.boards.ie/discussion/comment/120016894#Comment_120016894

Apart from the other issues you mentioned, the issue of entering at an angle hadn't occurred to me. Personally, I have limited neck rotation and have to adjust my vehicle orientation to ensure I can see to my right at such junctions. I've two choices, use my mirrors to merge from a merging lane, or if there is no merging lane stop with my vehicle at 90° to the road I'm joining and quickly apply full left lock when taking off.

lawrencesummers

https://www.boards.ie/discussion/comment/120017027#Comment_120017027

personally i prefer to use my mirrors for merging because there is less of a blind spot, but there is the OP that bad drivers are bad drivers, but bad drivers in a bad junction is a dangerous recipe.

There is a small merging lane onto the south link inbound where cars frequently get to the end of the short merging lane and have to stop, traffic volumes are a different level but

I can see the junction being an issue, i travel the road a small bit but havent been on it yet.

Also its not just the entrance to the new road that could cause problems, the exit could be problematic, lead to late breaking, confusion, drastic lane changing and exiting at high speeds

arsebiscuits82

Been using the junction since the day it opened both directions and haven't had or seen an issue yet. The traffic volume on the road is small enough in reality.

It's not like joining onto the M50!

9 times out of 10 the traffic approaching move out to the passing lane once they see a vehicle at the junction.

niloc1951

https://www.boards.ie/discussion/comment/120017406#Comment_120017406

I would have said 9 out of 10 don't move over, that road must have an exceptionally high proportion of courteous drivers.

IMHO the majority of Irish drivers seem to have a box 'em in mentality when it comes to merging traffic or drivers indicating to move to the overtaking lane to get past slower traffic, a sort of this is my lane stay away thinking.

yannakis

Love how most of the replies to the compact junction layout are focusing on how drivers on the N22 could or should fix errors from drivers merging.. instead of looking at issue itself.

People who will be familiar with the junction will learn how to stop when merging and to anticipate a lane change when travelling on N22. Everyone else will be either oblivious or confused.

If the same mistake keeps happening, the road design is flawed. In my opinion, at this particular junction, the Stop sign will be missed over and over because it's placed on a shallow curve where drivers are expected to be looking diagonally over their right shoulder for oncoming traffic.

Jayuu

While I'm not entirely in favour of the compact junction layout the question has to be whether there is enough signage on the junctions and the approaches to them so that drivers know what's coming and how they should behave. Unfortunately Google Maps doesn't have a street view of the junctions yet so I can't tell what is or isn't present.

There comes a certain point where we can't (or shouldn't attempt to) design out every possible thing that drivers could do and assume that if you are in charge of a vehicle that can travel at speed you have a responsibility to know how to read the road signage and behave appropriately according to the rules of the road. I know that's probably wishful thinking but it does frustrate me that driver responsibility is far too often ignored in favour of trying to design out stupidity.

cantalach

I used the new junction the other day to enter the N22 eastbound from the Millstreet Road. Pains me to be so critical, but the compact junction implementation there seems poor to me. It is a certainty that people will drive through that Stop sign without looking. Its positioning means that it is easily missed. I was surprised too how long I was waiting at the Stop sign for a usable gap in the slow lane, thanks to a little bunch of 4 cars in the slow lane, none of whom moved over to the fast lane to let me join (as is their prerogative). I’ll be surprised if there isn’t a significant rethink at that junction within a few years.

cantalach

https://www.boards.ie/discussion/comment/120044116#Comment_120044116

I would have said something similar having driven the bypass a few times…until I actually used the junction the other day. If I can borrow lingo from another branch of engineering, even a good design pattern can have a poor implementation, and I think that is the case here.

niloc1951

https://www.boards.ie/discussion/comment/120044116#Comment_120044116

We passed over that rubicon many moons ago. Just look at modern vehicles with auto dipping headlights, auto wipers, lane divergence warnings, auto braking, etc., etc., etc. Stupidity has now long been designed out which is why the capability of driving properly is being steadily eroded away among the general population.

niloc1951

https://www.boards.ie/discussion/comment/120044191#Comment_120044191

thanks to a little bunch of 4 cars in the slow lane, none of whom moved over to the fast lane to let me join (as is their prerogative)

It's not really their prerogative, it's a display of bad driving without consideration for other road users.

Being a regular driver in other countries I'm always disappointed by the 'box 'em in' attitude of most drivers here, moving across to the next lane to allow other drivers to merge or momentarily easing off on the throttle to allow a vehicle ahead to overtake a slower vehicle seems to be a no-no here but is commonplace elsewhere.