View Full Version : Coldra Roundabout
I think this document details what's happening to the Coldra roundabout (albeit behind schedule).
http://www.swtra.co.uk/en/our_road_projects/project_data_capture/2.html
From the modeling of the traffic at the Coldra interchange and to increase the capacity for traffic flow, it is proposed that a new ?hamburger lane? underneath the existing M4 viaduct to allow traffic coming from the A449 to gain better access to the M4 westbound on slip will be constructed. There is also provision of new dedicated lane from the M4 westbound offslip to the Newport Southern Distributor Road, and a third lane off the Southern Distributor Road onto the gyratory, will provide increased capacity within the gyratory. The gyratory will also be widened to four lanes and minor modifications made to the A449 and Chepstow Road approaches. Roadmarkings and new signals will be installed as part of the works.
Looking at the image below, you can see that a 'hamburger' lane from the A449 to M4 west should make a big difference in terms of traffic flow.
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john.whythe
08 Dec 08, 3:47 PM
What is a Hamburger Lane? How in this example is it positioned to clear traffic from the roundabout but also duck under the existing flyover? Is there a diagram anywhere showing how it's all going to look when completed? :confused:
My understanding is that a new lane will be built from the A449 cutting across the roundabout and turning right onto the M4 west. I can see how this will help as the traffic from the A449 is probably the heaviest and the 'hambuger' lane wil redirect this traffic off most of the roundabout.
I haven't been able to find any on-line information of exactly how the finished works will look. Perhaps this is something that one of our councillors could acquire?
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From the Traffic Wales Web Site http://www.traffic-wales.com/10398
"24 Sept 2008
Work will start this week on a ?4.1m scheme to improve traffic flow around the Coldra roundabout at the A449 and Junction 24 interchange on the M4.
The Coldra Roundabout is a very busy junction connecting a number of strategic roads on the eastern side of Newport. The Junction has experienced increasing levels of congestion following a number of developments in Newport and along the M4 and A449. Consequently, the roundabout has now exceeded its design capacity for the number of vehicles that use it regularly.
The most significant and striking of the new improvements will be the introduction of a ?hamburger? arrangement, which will provide a new carriageway to route traffic between the A449 and the M4 Westbound entry slip road through the central island. This will be in combination with alterations to the A449 approach to Coldra Roundabout from the North and minor changes to the eastern end of the M4 Westbound entry slip road.
Together with a series of additional measures, this new arrangement is expected to significantly improve traffic flows at this busy interchange.
The Coldra is a major gateway to the city of Newport and landscaping is regarded as an important part of the improvement scheme. Newport Unlimited has been consulted to ensure compatibility of the landscaping with their proposals for the other gateways to the city.
The main contractor for the works is Alun Griffiths Contractors Limited and Capita Symonds, as Consulting Engineer, will supervise the works.
This is a busy section of the trunk road network and there is likely to be some disruption to road users whilst the works are in progress. Traffic management will be in place to protect the workforce, motorists and control the flow of traffic, and every effort will be made to minimise inconvenience to road users, local businesses and residents.
Further information can be obtained from the Welsh Assembly Government?s South Wales Trunk Road Agency on 01792 325 900 or e-mail enquiries@southwales-tra.gov.uk. "
Llangstone Community Council haven't seen the plans or any details of how the finished scheme will look like. Lets hope it works as intended!!
john.whythe
26 Mar 09, 4:47 PM
Following up my earlier question about exactly how the hamburger lane will be arranged vertically in order to clear the existing roundabout and the clear lack of information about it evidenced on this forum, I popped along to the Coldra the other day to ask the engineers themselves.
Apparently the new carriageway being constructed through the centre of the existing roundabout is being built 'at grade', which means that it will fully intersect with the roundabout itself. These new intersections will be light-controlled, so that the whole roundabout will be brought to a stop while traffic from the A449 proceeds to hamburger its way westwards onto the M4. The engineer himself said to me "and I would have thought that this will make things worse rather than better". It's difficult to see how it could be otherwise, really, so I'm depressed about the situation and can't understand how anyone with any sense could have designed it this way.
I guess the theory is simple..
If 50% of the traffic coming from Monmouth direction on to the Coldra is heading to Cardiff on the M4, then create a dedicated "overflow" route for it so that 50% less traffic gets caught up on the Coldra roundabout going to Magor or Newport etc.
Of course the trick is in the execution, how long and how much traffic do you leave to build up on the A449, before halting circulation on the Coldra to allow the A449 traffic to be released through its overflow route directly onto the M4 sliproad.
How "intelligent" will the traffic control system be ? It will presumably operate 24x7 , even in the small hours with little traffic.
We'll see :confused:
Work is certainly progressing and you can now clearly see how the 'hamburger' lane is going to look,
It also looks like their building a path down the A48 towards Langstone. Presumably this in preparation for the Ryder cup so people from Langstone can safely walk to the Celtic Manor.
It also looks like their building a path down the A48 towards Langstone.
or a cycle path ?
but to where? - to view the A449 and the wonderful "hamburger "lane
I cant see too many people walking from the Hilton towards the roundabout , you have to be brave at times to tackle the traffic inside your mobile steel box , let alone on foot or a bike :rolleyes:
people from Langstone can safely walk to the Celtic Manor
I thought that access by foot was banned for the Ryder Cup, if you want to go you have to drive to the park/ride ( Magor ?) and be coached back in - that'll be a green carbon foot print then :rolleyes:
A.Mifsud
30 Apr 09, 1:35 PM
Re walking to the Hilton. I have this awful feeling that they will put in a series of Zebra crossings for the Ryder Cup. Or maybe a lollipop person? Whatever, the current opening and closing of lanes around the roundabout is a nightmare. I close my eyes and hope for the best when we go round. Maybe I should mention ,I don't drive!
close my eyes and hope for the best
I think a lot of drivers do the same !
I emailed the South Wales Trunk Road Agency for any further information they could provide and they kindly sent the attached document.
It's a little technical but it does show you how the finished roundabout will look.
A.Mifsud
11 Jun 09, 1:56 PM
Interesting that the new footpath opposite McDonalds doesn't get a mention! There is a footpath upgrade near Holiday Inn but that seems to be it! Can't get my head round the thought of mixing pedestrians and the Coldra seems like a recipe for disaster on all levels?:eek:
Sunelectric
20 Jun 09, 10:08 AM
The swerving lane situation seems like an accident waiting to happen. As a local I find it very confusing - must be a nightmare for those travelling to the area!
davejpoole
30 Jun 09, 2:10 PM
Although I can see the sense in most of what has been done on the roundabout I think the new lane layout is ridiculous. There are new lanes suddenly appearing from the curbside and if you stay in the lane the signs tell you to be in you inevitably have to change lanes to get to your chosen destination. I think they've missed an opportunity to have put dedicated lanes in at every junction not just 2 of them. I suppose we'll just have to wait and see how it all turns out once its open.:confused:
Also there is now going to be so many traffic lights and pedestrian crossings I think our journey home is going to take a while longer which will inevitably force more traffic through the lanes past the golf course.
I've only used the roundabout half dozen times since the hamburger was opened but it seems a big improvement to me. My usual route langstone to Newport and actually getting onto the roundabout from the A48 is an awful lot quicker as there's effectively half the traffic coming past.
Even with the extra set of lights before you go onto the M4 West, I'm still finding it much quicker. However, I am taking this route at 0615 so I guess the real test will be during the rush hour.
I am still confused about the pedestrian crossings though. Where would anybody on foot wanting to be getting to or from via the Coldra roundabout?
davejpoole
01 Aug 09, 7:17 AM
Your right Admin, on first impression the improvements seem to be working but we'll wait and see what its like when the schools traffic is back in September.
Sunelectric
01 Aug 09, 7:44 AM
I agree. The true test will be a wet weekday morning (when schools are back).
Hands up if you have joined the Coldra from the Chepstow Rd ( Celtic Manor) side and failed to spot the set of lights that "protect" the hamburger exit ?
I was fortunate that no traffic was around :(
At some stage it appeared that a set of lights was installed for the Langstone traffic joining the Coldra - these have gone and a neatly filled pair of muddy holes are left on the verges !
kristie
01 Aug 09, 10:37 PM
I've only used the roundabout half dozen times since the hamburger was opened but it seems a big improvement to me. My usual route langstone to Newport and actually getting onto the roundabout from the A48 is an awful lot quicker as there's effectively half the traffic coming past.
Even with the extra set of lights before you go onto the M4 West, I'm still finding it much quicker. However, I am taking this route at 0615 so I guess the real test will be during the rush hour.
I am still confused about the pedestrian crossings though. Where would anybody on foot wanting to be getting to or from via the Coldra roundabout?
I (sometimes!) am brave enough to ride my bike to work, and have had to take my life in my hands getting from Langstone to Chepstow Road and back around the roundabout many times. I'll rest a lot easier now I can simply use the crossings. Also, whilst I was on maternity leave, it was a bit perilous crossing two motorway slip roads with a pram. So I am glad to see the crossings!
Have you seen the outbreak of Himalayan Balsam on the Coldra? This is the plant with pink flowers growing up to 2metres tall. It is highly invasive and the seed pods explode sending the seeds up to 7 metres away. It seems to have arrived in imported topsoil and taken over the roundabout in just a few weeks.
If it gets into your garden you may have trouble.
largedenims
21 Aug 09, 10:58 PM
I think it needs more lights myself just to confuse us even more :eek:
It does have electrified catseyes which flash on and off when traffic goes through the middle. The only problem is that the first day they used them the flashing lights gave a lady driver a seizure so they had to turn them off.
kristie
22 Aug 09, 7:33 AM
Have you seen the outbreak of Himalayan Balsam on the Coldra? This is the plant with pink flowers growing up to 2metres tall. It is highly invasive and the seed pods explode sending the seeds up to 7 metres away. It seems to have arrived in imported topsoil and taken over the roundabout in just a few weeks.
If it gets into your garden you may have trouble.
I think that they were cutting this down when I passed yesterday evening. At least there was man driving a mower through it.
Still there this morning and a lot of them as well.
I must admit that I was a bit sceptical about the "improvements" it would bring. However I've used the Coldra on numerous occasions since the new layout was fully opened & have found that getting on & off as well has moving around has improved tremendously. I think it's actually done what it was designed to do!!
Any other comments?
Sunelectric
25 Aug 09, 11:04 PM
I agree Alan but the true test will be when the schools go back and the bad weather kicks in.
Fingers crossed!
U following me about Sun? :D
Yes the true test will be the first 2 weeks of September but hopefully a lot of people will have got used to the new system, lets hope the new road layout can cope with the additional traffic during the school runs.
I'm definitely finding it a big improvement, even over the weekends. It's now so much easier getting onto the roundabout from Langstone and I'm finding the extra set of lights on the roundabout actually improve traffic flow.
But yes, the real test will be the start of the new term.
Wales Jay
28 Aug 09, 7:50 PM
Personally I have found the new "roundabout" system a great deal better. However, it remains to be seen when the new academic year (September) begins and the schools go back - I think that will be the real test. Also the sequence of the traffic lights need to be looked at i.e. the length of road as opposed to the red, amber, green sequence. As they are at present, will not cope with the volume of traffic experienced from September onwards. I would also like to know, purely out of curiosity, what the planners propose doing with the rest of the land e.g. "roundabout" on either side of the hamburger lane - couple of trailers selling tea/coffee/bacon sarnies!! could be good!! Or will we have plants/trees and advertisements for the Ryder Cup?:confused:
Sunelectric
29 Aug 09, 7:34 AM
Burger vans on either side of the roundabout isn't going to be an option. There would be limited on-foot customers, vehicles wouldn't be able to stop easily/safely and it would like look an eyesore. This would also be quite distracting.
The only way forward is landscaping...
Well, we're 2 weeks into the new School Run season & everything at the Coldra seems to be working OK. No problems getting out of the A48 from Langstone at any time of the day so far.
Very pleased with the whole thing, lets hope the landscaping is finished soon for a complete job :)
Alan
I hope I'm wrong but it feels like its only a matter of time before there is a serious metal bending accident
yesterday a car shot over a red light from Monmouth across the front of me whilst I came from the Cardiff M4 side towards Langstone.
The extra set of lights before th e Cardiff M4 entry are either difficult to see or too many are driving on auto pilot !
I've noticed several vehicles 'chancing' it as the light turns to red.
Having said that, I'm personally finding the improvement a big success :D. I've been on the roundabout now on several different times of the day and find it a lot smoother.
So, big thumbs up :thumb: to NCC, they got this one right.
I agree. I was sceptical beforehand but it really does handle the traffic well.
Just one minor point. Newport CC didn't have anything to do with it. The scheme was designed and paid for by the Welsh Assembly Government.
Thanks for the correction hayct. Hats off to the Welsh Assembly then.:yo:
A year on and the improvements do seem to have been a success :)
A few close encounters with other roadusers due to the lights at various points points on the roundabout. It can be very confusing over night when the roadworks are "active" and traffic cones "steer" you from lane to lane, whilst you try to spot the traffic lights !
My beef is that they don't remove the diversion signs after overnight roadworks on the M4. This makes life complicated/difficult for strangers to the area.
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