What are they doing with the N4?

bigpinkelephant

Hi,
I drive on the N4 every day through the roadworks (I come off at the M50 heading west). What exactly are they doing? There seems to be far too many traffic lights! I am hoping they are going to make an extra lane and also fix the Newcastle junction? The traffic on the N4 is terrible in the evenings.

fletch

That's exactly what they're doing

Ice_Box

file attached :cool:

bigpinkelephant

when will it be finished? I hope those extra traffic lights are only temporary?

Ice_Box

another file attached :cool::cool:

bigpinkelephant

Ice_Box wrote: »

file attached :cool:

that looks deadly!

Ice_Box

bigpinkelephant wrote: »

when will it be finished? I hope those extra traffic lights are only temporary?

NRA website says Q3 2009. But they already have the bridge in so it will probably finish early.

L1011

There'll be no lights on the N4 mainline from Palmerstown until the Sligo Throughpass once the Newcastle junction is finished - both those sets will be gone.

However, for the moment its only one more set than was there before!

bigpinkelephant

MYOB wrote: »

There'll be no lights on the N4 mainline from Palmerstown until the Sligo Throughpass once the Newcastle junction is finished - both those sets will be gone.

However, for the moment its only one more set than was there before!

Ah yeah but when you're late for work they make all the difference!

L1011

bigpinkelephant wrote: »

Ah yeah but when you're late for work they make all the difference!

The general experience on here so far is that the two light / part-roundabout system is actually pushing traffic through faster than the single lights ever did....

bigpinkelephant

MYOB wrote: »

The general experience on here so far is that the two light / part-roundabout system is actually pushing traffic through faster than the single lights ever did....

Maybe in the mornings but I am an hour getting from Tallaght to Maynooth in the evenings (leaving at 5.30) and it is only half an hour when I leave at 8am in the morning. I have tried M50>N4, I have tried Belgard Road>Fonthill Rd>N4, also Belgard Rd>N7>Outer Ring Road>Lucan, and can't get home any faster!

godtabh

bigpinkelephant wrote: »

Ah yeah but when you're late for work they make all the difference!

Not really. One is an on call pedestrian lights and doesn't affect the traffic as much as you would think during rush hour traffic.

The second set of lights all get triggered once a critical queue length is reached.

jimmycrackcorm

Ice_Box wrote: »

NRA website says Q3 2009. But they already have the bridge in so it will probably finish early.

Strangely enough, a lot of recent road projects have been completed in budget and early.

D'Peoples Voice

Ice_Box wrote: »

file attached :cool:

I assume that picture is incorrect,
I don't see the buslane,
unless it's like the flyover at Belfield college,
in which case the buses use the slip lanes,
which if that is the case, can I assume that both of those cars on the slip lane are using the bus lane? - not that thats anything new in Ireland!!!

L1011

Theres a bus stop outbound there as it is, which will need to be on the slip lane. Inbound doesn't have one IIRC but I suspect it'll go up and over too.

Heroditas

Am I correct in assuming there are no roundabouts on this intersection? If you come off the N4 to go up the Newcastle Road it appears from that picture that there will be no roundabout at the top of the off-ramp. This could work really well but by the looks of it, how can you get onto the N4 if you are coming down the Newcastle road to head east into town? If there are no roundabouts you will have to brave jumping across the traffic coming up from the village before swinging onto the ramp to head down onto the N4 heading east. Likewise if you're coming up from the village and wish to head onto the N4 heading west (however if you're in the village, I assume the exit/entrance by the Spa
is going to be closed off?)

Anyone any ideas? Sorry if I haven;t outlined it very well.

L1011

I would suspect there will be lights on the bridge. Maynooth (J7) interchange manages huge traffic flows with no lights and just an access control lane down the middle... but by 'manages', it can be quite bad.

Spa junction is unlikely to be touched, it may be run on up and over the Leixlip interchange though.

fletch

Heroditas wrote: »

Am I correct in assuming there are no roundabouts on this intersection? If you come off the N4 to go up the Newcastle Road it appears from that picture that there will be no roundabout at the top of the off-ramp. This could work really well but by the looks of it, how can you get onto the N4 if you are coming down the Newcastle road to head east into town? If there are no roundabouts you will have to brave jumping across the traffic coming up from the village before swinging onto the ramp to head down onto the N4 heading east. Likewise if you're coming up from the village and wish to head onto the N4 heading west (however if you're in the village, I assume the exit/entrance by the Spa
is going to be closed off?)

Anyone any ideas? Sorry if I haven;t outlined it very well.

Corss over the bridge and turn right on to the appropriate ramp

Heroditas

fletch wrote: »

Corss over the bridge and turn right on to the appropriate ramp

So like the Celbridge/Leixlip junction then? I guess they've had a hard look at what they need but I'm just wondering how bad that over-bridge may get in the morning if they develop Adamstown even more. It may be nigh on impossible to come up from the village and head west onto the M/N4 if you have a constant stream of traffic heading down the Newcastle Road looking to head east onto the M/N4.
Time will tell I guess.

Also I see Esker Lane is being closed off in a couple of weeks. That's another rat run closed off. Bit of a nuisance for me because I live right beside there and it was dead handy to nip out onto the N4 that way or nip home by cutting in there from the N4 but sure never mind.

aquascrotum

Heroditas wrote: »

Am I correct in assuming there are no roundabouts on this intersection? If you come off the N4 to go up the Newcastle Road it appears from that picture that there will be no roundabout at the top of the off-ramp. This could work really well but by the looks of it, how can you get onto the N4 if you are coming down the Newcastle road to head east into town? If there are no roundabouts you will have to brave jumping across the traffic coming up from the village before swinging onto the ramp to head down onto the N4 heading east. Likewise if you're coming up from the village and wish to head onto the N4 heading west (however if you're in the village, I assume the exit/entrance by the Spa
is going to be closed off?)

Anyone any ideas? Sorry if I haven;t outlined it very well.

Newcastle/Adamstown Road intersection with the N4 onslips will be traffic light controlled. Site space is limited to install roundabouts, and in any case any roundabout would probably be traffic light controlled. I'd say the possible negative impact to right turning traffic from N'castle is seen as a minor concern when compared to alleviating problems for the 40,000 vehicles/day (I think...) on the N4 mainline.

Davidth88

I guess they've had a hard look at what they need

Ho ho ho !



At the moment this is great , but until the kids were off school leaving down was horrible , coming into town is much better.

Esker lane being shut off will be a pain for me going to the ' Green dump ' also.

L1011

aquascrotum wrote: »

Newcastle/Adamstown Road intersection with the N4 onslips will be traffic light controlled. Site space is limited to install roundabouts, and in any case any roundabout would probably be traffic light controlled. I'd say the possible negative impact to right turning traffic from N'castle is seen as a minor concern when compared to alleviating problems for the 40,000 vehicles/day (I think...) on the N4 mainline.

I would suspect the impact will be equal to what it was before (off peak) to far less (on peak) for Newcastle -> N4 traffic anyway.

godtabh

Davidth88 wrote: »

Ho ho ho !

Esker lane being shut off will be a pain for me going to the ' Green dump ' also.

What part of esker lane is being closed up?

L1011

kearnsr wrote: »

What part of esker lane is being closed up?

The LILO between Ballydowd and Newcastle interchanges.

godtabh

MYOB wrote: »

The LILO between Ballydowd and Newcastle interchanges.

Thats just a temporay measure I assume?

If you get off at the Woodies flyover its not that longer of a trip

L1011

kearnsr wrote: »

Thats just a temporay measure I assume?

If you get off at the Woodies flyover its not that longer of a trip

No, its permanent.

godtabh

MYOB wrote: »

No, its permanent.

That will be a pain in the arse for people wantint to get to Esker Park, Esker Gleb etc

Davidth88

I think at that point ( where Esker lane juntion is )the N4 will be starting to dive
to go under the Newcastle juction so it was needed to close that entrance .

It wouldn't be that much of a pain if the lights on the ORR were not there, the roundabout worked perfectly , but as usual , why have a roundabout when 30000 lights working on a 4 min sequence will do .

I am completly at a loss at the obession with traffic lights here.

I take people points about turning west from Lucan when the overpass is finished , maybe they will put lights there .... on this occasion that would actually be the right thing to do .

godtabh

Davidth88 wrote: »

I think at that point ( where Esker lane juntion is )the N4 will be starting to dive
to go under the Newcastle juction so it was needed to close that entrance .

I thought it started a lot closer to the underpas?

Davidth88 wrote: »

It wouldn't be that much of a pain if the lights on the ORR were not there, the roundabout worked perfectly , but as usual , why have a roundabout when 30000 lights working on a 4 min sequence will do .

I am completly at a loss at the obession with traffic lights here.

That makes no sense to me. What are you talking about?

Davidth88

That makes no sense to me. What are you talking about?

With Esker Ln closed you have to come off at Woodies , turn left onto the outer ring road ( ORR ) then turn right at the lights . These lights used to be a roundabout that worked really well, since the lights have gone in the junction is horrible. To drive from Liffey Valley along to that junction down the road that run parralell to the N4 is impossible now , it used to work fine.

If it aint broke don't fix it , but it seems that here roundabouts have to be changed for lights , I have another one , exiting Park West onto Nangor Rd , used to be a roundabout , worked perfectly, now it's lights and its rubbish .


I was actually agreeing with you that it's going to be a pain for people .

I may be wrong about the diving underground bit , I was just assuming .

godtabh

Davidth88 wrote: »

With Esker Ln closed you have to come off at Woodies , turn left onto the outer ring road ( ORR ) then turn right at the lights . These lights used to be a roundabout that worked really well, since the lights have gone in the junction is horrible. To drive from Liffey Valley along to that junction down the road that run parralell to the N4 is impossible now , it used to work fine.

If it aint broke don't fix it , but it seems that here roundabouts have to be changed for lights , I have another one , exiting Park West onto Nangor Rd , used to be a roundabout , worked perfectly, now it's lights and its rubbish .


I was actually agreeing with you that it's going to be a pain for people .

I may be wrong about the diving underground bit , I was just assuming .

Right get you now.

That stretch of road always had problems on it. The roundabout didn't have the capacity to deal with the volumes of traffic.

Going from a roundabout to a signal controlled junction increases safety for all road users. It also means the queues can be controlled a lot more. It may mean that new queues form but they are managed more efficiently.

Don't know about Park West.

JHMEG

MYOB wrote: »

There'll be no lights on the N4 mainline from Palmerstown until the Sligo Throughpass once the Newcastle junction is finished - both those sets will be gone.

Carrick-on-Shannon has a pedestrian crossing.

L1011

JHMEG wrote: »

Carrick-on-Shannon has a pedestrian crossing.

Either I've run it every single time recently, or its not on the N4 mainlane...

I'm almost sure its in the village - Carrick is throughpassed (BADLY) remember.

Come to think of it, are they not on the junction of the road out to Leitrim Town and the main street?

Heroditas

Well, that's Esker Lane closed. I have to say that it won't massively affect me. I live in the Elmbrook area
and used to use that access road to nip down to Lucan Village but to be honest, it doesn;t take much longer going over the N4 at Woodies and then down into the village - particularly when you could have sat at the Newcastle lights for up to 5 minutes waiting to turn right to head down to the village.
We got an information pamphlet through the door from the local Green TD yesterday explaining how he'd tried to lobby to keep it open but to be honest, the more I think about it, the more it makes sense to close it off. That piece of road will essentially be a motorway when it's finished
and I wouldn't be too happy with the thought of
people coming out of that laneway and creeping along building up speed while the rest of the trafffic could be doing up to 100kmph on that stretch.

As an aside, does anyone understand why there is a buslane crossing from the north side to the south side of the N4 at that Woodies bridge? I'm unaware of any bus service going that direction. They all go the opposite direction however.

orbital83

MYOB wrote: »

Either I've run it every single time recently, or its not on the N4 mainlane...

I'm almost sure its in the village - Carrick is throughpassed (BADLY) remember.

Come to think of it, are they not on the junction of the road out to Leitrim Town and the main street?

Newtownforbes also has a set of pedestrian lights.
Try avoiding that one!

Heroditas

One of the lanes going inbound to Liffey Valley has now been moved into the centre of the road where the upgrades have been carried out. They're certainly rocketing through the work.
I'll try and take a photo and post one up later on.

lordgoat

OP

I go home most evenings from Leopardtown to maynooth but i go via the n7 and straffan. It's 40mins approx every evenings and there's no traffic once you get off the red cow which recently couldn't be better for traffic. Granted i am leaving at 6-6:30 in the evening.

I hate the N4 in the evening time.

Davidth88

The N4 in the evenings seems to have got a lot better in the last week, they must have adjusted the lights at the ' Roundabout ' at the Newcastle junction


Lets see what it's like the week after next when everyone is back from holidays

On Tuesday they indeed changed the layout coming into town. It was causing quite a hold up when I come in at 06:30 because the signposting was very misleading . It sort of indicated that if you wanted the N4 you had to stick to the outside lane and Lucan on the inside. I ignored this , and I was right , the inside lane did merge back in.

They should have put LUCAN/N4 on the inside lane and N4 on the outside....

Anyway by today everyone is used to it and traffic is nack to normal.

The are really getting on very fast , yesterday I was able to see ' under ' the underpass for the first time , ie the bridge is now a bridge without rock/ground under it. It's really impressed me the way the rock is coming out of the ground and you can see is being broken down on site to smaller peices and I think being reused. I am not a civil engineer so maybe I am easy to impress

Heroditas

Davidth88 wrote: »

The N4 in the evenings seems to have got a lot better in the last week, they must have adjusted the lights at the ' Roundabout ' at the Newcastle junction

Well certainly the lighting sequence is heavily weighted in favour of traffic staying on the N4. I've only used those lights once to go up the Newcastle Road from the N4 heading eastbound and despite only a couple of cars ahead of me in the queue, it took me a couple of sequences of lights to get through. They only seem t ostay green for traffic crossing the N4 for a couple of seconds. Can't wait until it's fully finished.

Victor

Heroditas wrote: »

As an aside, does anyone understand why there is a buslane crossing from the north side to the south side of the N4 at that Woodies bridge? I'm unaware of any bus service going that direction. They all go the opposite direction however.

I suspect thats for the bus lane on the outer ring road.

Heroditas

Victor wrote: »

I suspect thats for the bus lane on the outer ring road.

Oh I'd say so. However, no buses travel from the north end of the bridge to the south end.
Kinda wonder why they bothered even putting the bus lane there in the first place. Certainly the bus lane is used from the south end of the bridge down ont othe outer ring road (25A route). IMO it gives impatient drivers a lane to whizz across the bridge and undertake everyone. This happens a lot :mad:

Heroditas

Well all traffic inbound to town is now driving along the new surface. However, traffic outbound from the Foxhunter has now been funnelled into one lane on the new surface so traffic jams are quite bad. There was quite a large tailback on the N4 at 10pm last night due to this.
As a result, there seems to be a lot more traffic trying to squeeze down into Lucan village via the exit at Woodies/Foxhunter the last few days.

Has anyone any idea why the bus lane inbound towards the M50 is coned off? It certainly has stopped people queuing in the bus lane who are trying to exit northbound to the toll plaza.

However, this means they sit in the inside lane for Palmerstown essentially reducing the road into town to one lane. Oh please roll on the days when the toll plaza will be taken apart and the N4 finished.

L1011

Heroditas wrote: »

There was quite a large tailback on the N4 at 10pm last night due to this.
As a result, there seems to be a lot more traffic trying to squeeze down into Lucan village via the exit at Woodies/Foxhunter the last few days.

I was one of those going through the (empty) village at 10pm last night... queue didn't move more than a few cars in a 3-4 minutes so I bailed out.

gibo_ie

I assume the bus lanes are for Bus Eireann and private operator routes...

Heroditas

gibo_ie wrote: »

I assume the bus lanes are for Bus Eireann and private operator routes...

No buses EVER use that section though. In the time since that bridge has been opened, I have never once seen a bus in that lane cross the bridge. The only bit of that bus lane that is ever used is the section from the top of the slip road down as far as the turn for Penny Hill where the 25a turns left. No bus service heads down the outer ring road to the N7. Granted, a few coaches use it but the justification for its existence remains a bit of a mystery to me. It must be the emptiest bus lane in the country.

However, moving back to the bus lane crossing south over the bridge at Woodies; in my mind it would make more sense to have it as two lanes of traffic. The right hand one could then be purely for traffic turning right to head onto the N4 westbound.

L1011

Heroditas wrote: »

It must be the emptiest bus lane in the country.

N32 / ex-AerDart bus lane probably beats it

D'Peoples Voice

Heroditas wrote: »

No buses EVER use that section though. In the time since that bridge has been opened, I have never once seen a bus in that lane cross the bridge.

Relax there, I believe Dublin bus are using as many of their buses to compete on the same routes as private operators to run them out of business.:D When that is achieved, I'm sure they will move some of those buses from those captured routes to run Tallaght - Lucan on the Outer Link Road:D and let the service on those captured routes fall back to their normal service levels:D

call me a cynic....

Heroditas

D'Peoples Voice wrote: »

call me a cynic....

You're a cynic

ohnoigotsick

Heroditas wrote: »

One of the lanes going inbound to Liffey Valley has now been moved into the centre of the road where the upgrades have been carried out. They're certainly rocketing through the work.
I'll try and take a photo and post one up later on.

how is this coming along folks ?

L1011

Last time I was along it, both lanes between Newcastle X and Woodies were running on the new tarmac in the centre of the road, and also between Newcastle X and the M4.

There seems to have been very very little progress on Woodies to Liffey Valley though - one side of the road is already 3 lanes here.

The deck is on the new bridge, the inbound (east) side had been dug out already and the outbound (west) side was nearly dug out. The base of the barrier was in along the inbound side too.

gibo_ie

From this morning, traffic is still on the same lanes as it has been for the past two months. The eastbound city side of the new bridge has had tarmac laid and shows three lanes in each direction (yet to be marked). Lamp posts are up on both sides and on the western side of the bridge they are marking out for the central barrier this AM and compacting the stone beneath getting ready for surface.

I guess that by end of this week they will have surfaced the western lanes.

They were also filling in between the eastern turnabout junction and the new lanes with tar at 9am today too.

Bridge is concrete surfaced with temporary wooden rails along side. On the southern end they were digging out and compacting stone this morning also.

As already said, between the Newcastle Road Jn and Liffey Valley they have basically abandoned this part for now. Very little work done, however these guys seem to hit an area hard and get it running so maybe not too long now...