Upgrade of M50 to cause traffic constraints

Navan Junction

Irish Times, 27/07/2006

From the first week of August motorists using the M50 will face traffic restrictions along a 7km (four miles) stretch between the N4 interchange and Ballymount as construction starts on the upgrade of Dublin's chronically congested orbital route, writes David Labanyi.


The N4 and N7 interchanges within this section will be redesigned to create a "free flow" system that will not require traffic lights. An extra lane is being added in each direction on the M50 along with a fourth lane linking adjacent interchanges.

This extra lane is to allow traffic going from one interchange to the next to remain separate from the main body of traffic on the M50. When complete, the M50 will have a hard shoulder.

John Glynn, project manager with lead contractor SIAC-Ferrovial, said the speed limit on this section of the M50 will be reduced to 60km/h (37mph) during the construction.

He admitted that trying to minimise traffic congestion on a route handling up to 100,000 vehicles a day was the most complicated part of the project and that disruption was "unavoidable" during the construction stage.

However, by using "quite a complex system" of road layout changes and giving motorists regular updates on restrictions, Mr Glynn said capacity on the route would not be significantly affected.

To reduce driver confusion, details of layout changes at junctions and along the M50 will be published in local and national media and will also be available on a website, he said.

Mr Glynn said two lanes in each direction would remain open to traffic between 6am and 10pm but outside these peak times intermittent traffic restrictions would apply.

To reduce traffic congestion much of the building work will take place at night.

One of the first changes motorists will experience will be M50 traffic pushed on to the hard shoulder and the slow lane to allow construction begin along the central median.

What is now the inside lane will be reserved for emergency vehicles, allowing them to reach any possible crash.

The land required to widen the M50 will come primarily from placing additional lanes on what is now the central median and also narrowing existing lanes slightly to 3.5 metres. This is the standard lane width. Once building is complete, north-bound and south-bound traffic will be separated by a concrete barrier.

Hugh Creegan, NRA head of programme management, said the Ballymount interchange would also be upgraded under the first phase of works but not to a "free flow" system.

Access lanes to and from all the interchanges along the M50 will also be upgraded.

Mr Glynn said when work on the central median was completed, traffic would be temporarily switched to one side of the motorway while work was completed on the other, before being switched back again.

Because the additional M50 lanes will run along what is now the median, no extra land is required for the upgrade, although extra land has been purchased to accommodate the new, larger interchanges. However, once completed, the current upgrade on the M50 is the limit of extra capacity possible.

If future demand runs over the capacity of the upgraded M50, Mr Creegan said demand management measures would be required. A number of these were currently being assessed, he said.

Mr Glynn added that barriers would be erected near housing to reduce the impact of noise and dust during construction.

Work on the section between the N4 and Ballymount is expected to last two years and will cost €244 million, including land acquisition costs, according to the NRA.

The section between the N4 and Ballymount will be the first part of the 32km-long M50 upgraded to six lanes. The overall project is expected to be completed by 2010.

© The Irish Times

Navan Junction

Irish Independent, 27th July 2006

MOTORISTS have been warned to brace themselves for even worse traffic chaos on the M50 when the first phase of the three-lane upgrade begins next month.

Although two lanes will be kept open in each direction, the speed limit will be reduced from 120kmh to 60kmh for the section between Ballymount and the N4 roundabout.

South Dublin Co Council said that motorists could experience delays which would be worse than those already seen there. "We can't deny it is possible but we're trying to minimise the conditions that lead to delays," said director of transport Frank Coffey. "We are going to provide something that will hugely improve traffic flows in the area and it causes some grief while we are putting it in place."

Under phase one of the €800m M50 upgrade, the contractors SIAC and Ferrovial will add another lane in each direction, as well as a dedicated lane for motorists travelling between Ballymount and the N4.

There will also be a new 'spaghetti junction' at the N4 which will replace the existing roundabout.

SIAC project manager John Glynn said the contractors would push the traffic into the slow lane and the hard shoulder, which would free up the area around the grass median. "But in that area, we're including a dedicated emergency lane so that the emergency services can get through," he said.

When the new roadway has been built, all of the traffic will be shifted to one side of the M50 and construction work will take place on the outer lane.

"Similarly, when we have this constructed, we swing the traffic back and we construct the other zone, and we're done," said Mr Glynn.

He said much of the heavy construction would be done at night and that more pre-cast concrete structures would be used to speed up the process.

Drivers will have to take more care because the temporary lanes will be 3.25m wide, compared to the existing 3.75m lanes. The contractors will build temporary roads at the N4 roundabout to shift traffic so new bridges and slipways can be put in place.

The first phase of the M50 upgrade, which is costing €244m, is expected to be completed in 2008. The National Roads Authority (NRA) is putting the 24km section from the N7 Red Cow roundabout to the N3 out to tender, as well as the section from the N3 to the M1. The entire project will be completed by 2010.

The upgrade will double the capacity of the M50 to 200,000 vehicles but with traffic volumes increasing so quickly, there is a possibility that it will soon be choked up with cars again.

NRA project manager Hugh Creegan said an Bord Pleanala had asked for demand management features such as tolls to be looked at. "By the time this is built, we'll have a clearer idea of when those demand management features are required and what they might be," he said.

Michael Brennan

Moanin

Great!

mysterious

fufen great:D

There is land on the edges in some parts to widen it further. The ultimate reason why "they" say it's not possible to widen the road, when they have filled in the Median, is because the bridges are at maximum width for the new lanes that will pass underneath. For example the Redcow bridge is serioulsy narrorer than most stretches I've seen on the M50, and it looks tight to even add another lane there as it is. That's is the reason, why they cannot find it possible to widen the M50mainline.

Why can't they just build another bridge beside the existing one, and when completed, knock the old one. Therefore the new bridges will be longer and wider, for maybe four lanes with an additional auxillary lane.

I laughed at the point, that N4 and N7 will be freeflow. N7 will have numerous traffic lights on many arrangement from southbound to Northbound, and including Monastery road turn off, ffs a joke. No harm in mentioning it....

Any cloverleaf/ free flow interchange built in Britain, even back in 60s etc, are still majestic compared to these free flow arangements, and probably cost a quarter of the ones we are building. Sadly we won't see a proper free flow interchange in this country for a long time.

There's plenty of land between the N3 and N4 for separte auxillary lanes, if wished,to run along side the N4 slip and onto the N3 without joining the M5O (westlink) at all. By means of building a two lane northbound bridge over the Westlink (which shouldn't be to expensive and seperate from the existing bridge) coming from the N4 and allowing this traffic that want to go enroute to Blanch, city, N3 etc.. without having to avalanch onto the heavily congested bridge... just amazing thoughts of mine, (in this country it would seem horribly ambitous)

darkman2

mysterious wrote:

fufen great:D

There is land on the edges in some parts to widen it further. The ultimate reason why "they" say it's not possible to widen the road, when they have filled in the Median, is because the bridges are at maximum width for the new lanes that will pass underneath. For example the Redcow bridge is serioulsy narrorer than most stretches I've seen on the M50, and it looks tight to even add another lane there as it is. That's is the reason, why they cannot find it possible to widen the M50mainline.

Why can't they just build another bridge beside the existing one, and when completed, knock the old one. Therefore the new bridges will be longer and wider, for maybe four lanes with an additional auxillary lane.

I laughed at the point, that N4 and N7 will be freeflow. N7 will have numerous traffic lights on many arrangement from southbound to Northbound, and including Monastery road turn off, ffs a joke. No harm in mentioning it....

Any cloverleaf/ free flow interchange built in Britain, even back in 60s etc, are still majestic compared to these free flow arangements, and probably cost a quarter of the ones we are building. Sadly we won't see a proper free flow interchange in this country for a long time.

There's plenty of land between the N3 and N4 for separte auxillary lanes, if wished,to run along side the N4 slip and onto the N3 without joining the M5O (westlink) at all. By means of building a two lane northbound bridge over the Westlink (which shouldn't be to expensive and seperate from the existing bridge) coming from the N4 and allowing this traffic that want to go enroute to Blanch, city, N3 etc.. without having to avalanch onto the heavily congested bridge... just amazing thoughts of mine, (in this country it would seem horribly ambitous)

I actually disagree. The N7 interchange will be fine when finished on the approaches that matter. The N4 will be a perfectly freeflow interchange and there will be 4 lanes each way on this section so its fine, I dont see a problem here:rolleyes:

Chris_533976

lmao at the difference between the informational report in the Times and the sensationalist crap of the Independent.

Irish Times, 27/07/2006

From the first week of August motorists using the M50 will face traffic restrictions along a 7km (four miles) stretch between the N4 interchange and Ballymount as construction starts on the upgrade of Dublin's chronically congested orbital route, writes David Labanyi.

Irish Independent, 27th July 2006

MOTORISTS have been warned to brace themselves for even worse traffic chaos on the M50 when the first phase of the three-lane upgrade begins next month.

mackerski

mysterious wrote:

Any cloverleaf/ free flow interchange built in Britain, even back in 60s etc, are still majestic compared to these free flow arangements, and probably cost a quarter of the ones we are building.

There are no cloverleaf interchanges on the UK motorway network, nor were there ever. There are only three on the entire road network. This is a Good Thing, since they have poor capacity and weaving issues that would be particularly trying on an Irish road.

mysterious wrote:

Sadly we won't see a proper free flow interchange in this country for a long time.

M7/M9.

Dermot

Andrew Duffy

M50/M11 and M4/M6 are of the same type. There are plenty of free-flowing trumpet interchanges on dual and single carriageways around the country too.

mysterious

mackerski wrote:

There are no cloverleaf interchanges on the UK motorway network, nor were there ever. There are only three on the entire road network. This is a Good Thing, since they have poor capacity and weaving issues that would be particularly trying on an Irish road.



M7/M9.

Dermot

I meant the criss cross interchange not the cloverleaf. Can't remember the name of them, but a replica of what I'm talking about is the
M4/M25.

Red cow is not good enough. The will still have lights M50/ city bound coming from Naas/Limerick, and that's even before the interchange.... In 5 years time, I can honestly say thet will have to go back to the drawing boards to sort out the traffic on this horrendous spot. " et la Mad cow"

mysterious

Andrew Duffy wrote:

M50/M11 and M4/M6 are of the same type. There are plenty of free-flowing trumpet interchanges on dual and single carriageways around the country too.

I don't think there are many. If they meet a roundabout, it's not exaclty free flowing arangements. I mean there are a lot of Trumpet type interchanges like the Naas globe flyover, but it meets at lights and a roundabout etc. so the free flowing arangement is defeated.

One example of a free flowing trumpet interchange, the N25/N28 Ringaskiddy.

bryanw

Well it's good to see that the M50 work is being started. I see they have (kinda) started some of the work on the interchanges already... they have machinery and clearance stuff.

I don't know if the 60km speed limit will make much difference though, most of the time the traffic is crawling along at less than that anyway.

The upgraded N7 Nass road is actually a very nice road, three lanes working very well. Hope they do on the M50. N7 is looking all French with its double-barrier median ! I though the traffic seemed to move very well on the road and seemed light. I don't know if that's because the 3 lanes actually work or because it's July and everyone's on holidays...

mackerski

mysterious wrote:

I meant the criss cross interchange not the cloverleaf. Can't remember the name of them, but a replica of what I'm talking about is the
M4/M25.

Four-level stack. Three in the whole UK, two of them on the M25. Don't hold your breath for the Brits to build any more of them TBH, they are mucho expensive and way overspec for anything Ireland needs.

Dermot

mysterious

mackerski wrote:

Four-level stack. Three in the whole UK, two of them on the M25. Don't hold your breath for the Brits to build any more of them TBH, they are mucho expensive and way overspec for anything Ireland needs.

Dermot

ok I hear ya.

Let's just say that current plan goes accordingly. I.e M50 finished. 10 years time the Redcow just cannot cope with the level of traffic. Which will be at capacity at Monastery road on ramp. Due to the very tight arrangements and the Luas, I just can't imagine a proper easing flowing interchange.

Again let's just say money is availeable in 10-15 years time for the N7. What can be done to the interchange to improve it or just sort out the conflicting movements. The Northbound lanes approacing the luas and outbound lanes will be congested.... Am I being to far stretched, or does anyone agree that it will be heavily gridlocked, while the N4 moves reasonably ok.

Chris_533976

The next logical plan would be a suggestion of mine Start the outer orbital by building a freeflow motorway link between the M7 and N4.

Victor

mysterious wrote:

Again let's just say money is availeable in 10-15 years time for the N7. What can be done to the interchange to improve it or just sort out the conflicting movements. The Northbound lanes approacing the luas and outbound lanes will be congested.... Am I being to far stretched, or does anyone agree that it will be heavily gridlocked, while the N4 moves reasonably ok.

Build the M7 and Junction 8.

murphaph

Victor wrote:

Build the M7 and Junction 8.

That's been all but knocked on the head forever now. Atkins prepared a report about that and it concluded that adding another junction (and it's inherent weaving movements) on what is already the busiest part of the M50 would do nothing but slow traffic down still further.

There are some things they could do in the future to improve the silly proposed Red Cow. Closing Monastery Road access onto the N7 would be a start!

That eliminates a set of lights and automaticaly grants freeflowing N7->M50 movemens. Then they could do as Seamus suggested, stick the Luas on 'stilts'. Don't know why the pathetic media here lampooned him for that, one of his more sensible utterings!

That would allow freeflowing M50(NB)->N7, R110->N7 and possibly M50(NB)->R110 IIRC.

They WILL return to this junction in under 10 years to rectify at least some of the shortcomings of the proposed interchange.

Hotblack Desiato

mysterious wrote:

There's plenty of land between the N3 and N4 for separte auxillary lanes, if wished,to run along side the N4 slip and onto the N3 without joining the M5O (westlink) at all. By means of building a two lane northbound bridge over the Westlink (which shouldn't be to expensive and seperate from the existing bridge) coming from the N4 and allowing this traffic that want to go enroute to Blanch, city, N3 etc.. without having to avalanch onto the heavily congested bridge... just amazing thoughts of mine, (in this country it would seem horribly ambitous)

Don't NTR have the right to toll any bridge over the Liffey at that point?