End of the M48?

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JohnnyMo
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Re: End of the M48?

Post by JohnnyMo » Wed Oct 20, 2021 10:34

Is the issue the Highbeech Roundabout A48/A466 is congested ? If so fix that.
I can see how that roundabout can become unbalanced at peak times and cause the A48 to back up.

I assume the A48 is a "busy" S2 but nothing more. In an ideal world Chepstow should have a better bypass but given the geography that will not be cheap and is not going to happen.

I can't see M48 Jct 2 being too congested as it just has a single S2 A Road and a couple of minor roads, nor can I see any other place to put a motorway junction to serve Chepstow better.

Some people keep referring to improving local transport links now the M48 has lost its' national importance can someone say what there are
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Re: End of the M48?

Post by KeithW » Wed Oct 20, 2021 11:49

trickstat wrote:
Tue Oct 19, 2021 15:18
If your intended destination is Chepstow or the Wye Valley then it makes sense.
Indeed and in 2018 I took that route from Cornwall to Monmouth with a stop at Tintern Abbey to take a few snaps. Rather a pleasant drive on a sunny afternoon in July.

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Re: End of the M48?

Post by KeithW » Wed Oct 20, 2021 12:12

I have no dog in this race but I feel constrained to raise a simple question.

When congestion occurs what is the cause ?

The traffic volumes dont seem that high frankly, I know of roundabouts that are much busier that cope tolerably well except at certain periods of the day when one road carries considerably more traffic than the other. From what I can see on GSV the roundabout does not seem to be signalised. The AADF on the A466 is around 20k so I can see that at peak getting into the traffic flow might be a problem. In an ideal world yes the A48 at Chepstow should have a bypass but where would it go ?

A northern bypass seems a non starter due to the presence of the racecourse and the local topology. There is no southern option unless you go in for mass demolition.

So the only option is to fix the A48/A466 roundabout . In theory you could put the A466 on a flyover but I dont see that happening. I see from GSV that the desire route from the A466 to the A48 heading NE has been blocked off.
https://www.google.co.uk/maps/@51.63651 ... 6656?hl=en

Realistically I suspect that the best that could be expected is to install a Hamburger roundabout as was done at the A66/A171 junction here.
https://www.google.co.uk/maps/@54.57510 ... !1e3?hl=en

However this is a much busier junction than the A48/A466 so realistically all I expect is that the roundabout will be signalised.

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Re: End of the M48?

Post by booshank » Wed Oct 20, 2021 14:32

KeithW wrote:
Wed Oct 20, 2021 12:12
I have no dog in this race but I feel constrained to raise a simple question.

When congestion occurs what is the cause ?

The traffic volumes dont seem that high frankly, I know of roundabouts that are much busier that cope tolerably well except at certain periods of the day when one road carries considerably more traffic than the other. From what I can see on GSV the roundabout does not seem to be signalised. The AADF on the A466 is around 20k so I can see that at peak getting into the traffic flow might be a problem. In an ideal world yes the A48 at Chepstow should have a bypass but where would it go ?

A northern bypass seems a non starter due to the presence of the racecourse and the local topology. There is no southern option unless you go in for mass demolition.

So the only option is to fix the A48/A466 roundabout . In theory you could put the A466 on a flyover but I dont see that happening. I see from GSV that the desire route from the A466 to the A48 heading NE has been blocked off.
https://www.google.co.uk/maps/@51.63651 ... 6656?hl=en

Realistically I suspect that the best that could be expected is to install a Hamburger roundabout as was done at the A66/A171 junction here.
https://www.google.co.uk/maps/@54.57510 ... !1e3?hl=en

However this is a much busier junction than the A48/A466 so realistically all I expect is that the roundabout will be signalised.
I use this to get to the Forest of Dean from time to time so I'm fairly familiar with the M48-A466-A48 route (but not so much with the other two main arms of that roundabout). The main problem seems to be the bottleneck that Chepstow forms on the A48. NE bound traffic builds up on the A48 through Chepstow, especially on the hill before the Wye bridge, and then backs up to the Highbeech roundabout and the whole thing gets clogged up once traffic from the M48 direction can't exit the roundabout towards Chepstow.

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Re: End of the M48?

Post by JohnnyMo » Wed Oct 20, 2021 14:56

That sounds like the phasing of the light as Mount Pleasant (Tesco) is wrong, I can't see how else a S2 thru a town will get congested as it leaves the town.

Alternative solution is extend the 30mph zone to Glostershire, which should increase the capacity on the bridge :coat:
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Re: End of the M48?

Post by KeithW » Wed Oct 20, 2021 15:50

booshank wrote:
Wed Oct 20, 2021 14:32

I use this to get to the Forest of Dean from time to time so I'm fairly familiar with the M48-A466-A48 route (but not so much with the other two main arms of that roundabout). The main problem seems to be the bottleneck that Chepstow forms on the A48. NE bound traffic builds up on the A48 through Chepstow, especially on the hill before the Wye bridge, and then backs up to the Highbeech roundabout and the whole thing gets clogged up once traffic from the M48 direction can't exit the roundabout towards Chepstow.
That makes sense, the AADF NE of Chepstow is over 20k which is very high and is about the same level as that on the S2 A172 where queues form for the Stainmore Way and Ladgate lane junctions.

This being the case one option may indeed a hamburger junction with the A466 going through the middle but I suspect they will first try signalising the roundabout. I looked at the plans for a bypass but my first guess is it has no chance of approval especially given the opposition of the Welsh government to new road building.

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Re: End of the M48?

Post by Beardy5632 » Wed Oct 20, 2021 16:23

Those lights by Tesco have had phasing issues for years. If I ever need to head into or through Chepstow it can sometimes be quicker crossing the old Wye bridge and using the one way system to get to them as the A48 bridge can often queue if you catch it at the wrong time.

The other more recent problem is due to the pandemic the main street is currently closed to traffic (they used to only close it on a market day) so anything wanting to get from say Welsh Street car park back to the Forest has to use part of the A48 through the town. There were calls from locals to reopen it a few months ago when the A48 at the Bulwark turning was shut due to a bad crash because of a lack of a diversion.
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Re: End of the M48?

Post by Gareth Thomas » Sun Oct 31, 2021 12:18

The article does seem to suggest that the only two options are “change to A-road and then build junctions”, and “do absolutely nothing”. And if that really were it, then I’d say go for the former. But surely it would be easier to build a Junction 3 at Crick (as suggested by others in this topic) to serve Caldicot and Caerwent, and keep the blue line going to Chepstow? It wouldn’t serve traffic issues in Chepstow itself, but it would take some traffic away from Magor and relieve the B4245.

If the M49 can get a new junction built for an industrial estate then surely the M48 can for actual settlements?

And keeping the M48 number also makes it clear that the route is an alternative to the M4 in the event of a bridge closure, plus the blue line near Chepstow would possibly help keep investment in the town? I remember there was a campaign to extend the M54 to Shrewsbury a while back because the theory was a blue line on the map would bring more investment to the area.
Last edited by Gareth Thomas on Mon Nov 01, 2021 15:12, edited 3 times in total.
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Re: End of the M48?

Post by M4 Cardiff » Sun Oct 31, 2021 16:33

Could there also be a tiny bit of advance planning for the old Severn Bridge reaching the end of its design life and becoming unsuitable for repair or life extension and having to be demolished? I'd assume it had a 100 year design life, and is now around 60 years old.

This level of forward planning would also make sense with respect to the layout of the proposed replacement J23 of the M4, if the Newport southern bypass ever gets built.
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Re: End of the M48?

Post by skiddaw05 » Sun Oct 31, 2021 17:04

M4 Cardiff wrote:
Sun Oct 31, 2021 16:33
Could there also be a tiny bit of advance planning for the old Severn Bridge reaching the end of its design life and becoming unsuitable for repair or life extension and having to be demolished? I'd assume it had a 100 year design life, and is now around 60 years old.

This level of forward planning would also make sense with respect to the layout of the proposed replacement J23 of the M4, if the Newport southern bypass ever gets built.
I'm about the same vintage as the Severn Bridge and hope I get to the end of my design life before the bridge does, it would be an absolute travesty if it was to be removed

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Re: End of the M48?

Post by trickstat » Sun Oct 31, 2021 17:51

skiddaw05 wrote:
Sun Oct 31, 2021 17:04
M4 Cardiff wrote:
Sun Oct 31, 2021 16:33
Could there also be a tiny bit of advance planning for the old Severn Bridge reaching the end of its design life and becoming unsuitable for repair or life extension and having to be demolished? I'd assume it had a 100 year design life, and is now around 60 years old.

This level of forward planning would also make sense with respect to the layout of the proposed replacement J23 of the M4, if the Newport southern bypass ever gets built.
I'm about the same vintage as the Severn Bridge and hope I get to the end of my design life before the bridge does, it would be an absolute travesty if it was to be removed
Well it is 29 years younger than the Golden Gate Bridge which has a longer main span and is still very much in use.

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Re: End of the M48?

Post by M19 » Sun Oct 31, 2021 21:56

The Welsh do seem to be conflicting themselves with this. On the one hand they’re against diverting the M4 south of Newport because it will increase traffic among other reasons, yet are keen enough to for getting more traffic onto the M48 by downgrading it?

Now you could look at this another way. The Severn Crossing and new southerly diverted M4 becomes the long distance strategic M4 with minimal connections. Meanwhile the old Newport bypass section of M4 becomes the M48 and remains separate from the M4 to deal with local traffic as a collector/distributor route.

I can’t see how it can be worryingly expensive for an extra junction near Caldicot because it’s a motorway. I’m thinking of work quite recently to add west facing slips at the M876 J2. And, anyway, with Wales declaring a “Climate Emergency” should the locals be expected to use public transport or stay at home if they can’t? I thought a new Metro was planned to solve all of that?
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Re: End of the M48?

Post by Owain » Wed Nov 03, 2021 09:23

JohnnyMo wrote:
Wed Oct 20, 2021 10:34
Is the issue the Highbeech Roundabout A48/A466 is congested ? If so fix that.
I can see how that roundabout can become unbalanced at peak times and cause the A48 to back up.
That doesn't help, but as you pointed out in a later post, the two sets of traffic lights in close proximity near the Tesco might be the bigger problem. That store was not there until after the new Wye Bridge and A48 bypass of Tutshill were built. Instead, there was a Rover dealership, and a patch of wasteland. The Tesco has obviously generated an enormous amount of extra local traffic, than the road would have otherwise had to cater for.

JohnnyMo wrote:
Wed Oct 20, 2021 10:34
I can't see M48 Jct 2 being too congested as it just has a single S2 A Road and a couple of minor roads, nor can I see any other place to put a motorway junction to serve Chepstow better.
The A466 extension from the A48 to the M48 J2 is actually S2+1; the +1 swaps over half way along in favour of traffic approaching the roundabout at each end. That, in itself, works perfectly well.

One quirk of M48 J2 is that traffic exiting the motorway from the direction of the Severn/Wye Bridges tends to take the left-hand lane to turn right at the roundabout for the A466. This convention dates back to when the roundabout had only two arms other than the motorway slips; one for the large trading estate to the south of the motorway, and the other for the A466. As little traffic entered the trading estate, the vast majority of traffic used the left-hand lane for the A466, and the right-hand lane was largely wasted. EDIT - A look on GSV suggests that there are now lane markings in place to instruct traffic, but these are recent; for most of its history there was no filtering of traffic. Just two lanes!

The unclassified road that now leads to Bulwark is a relatively recent addition.

KeithW wrote:
Wed Oct 20, 2021 12:12
When congestion occurs what is the cause ?

The traffic volumes dont seem that high frankly, I know of roundabouts that are much busier that cope tolerably well except at certain periods of the day when one road carries considerably more traffic than the other. From what I can see on GSV the roundabout does not seem to be signalised. The AADF on the A466 is around 20k so I can see that at peak getting into the traffic flow might be a problem. In an ideal world yes the A48 at Chepstow should have a bypass but where would it go ?
In my experience, the two sets of lights in close proximity near Tesco cause the bulk of the problem; or, rather, the poor lane provision at those lights. If you look on GSV, there is effectively only one lane in each direction, even though they are separated by a tiny dual carriageway.

Heading eastbound, you get a right-turn filter for Tesco and the railway station, which isn't really long enough considering how much traffic wants to turn in there. Then you get two 'straight ahead' lanes at the second set of lights, but few wish to line up in the outside lane because both lanes merge into one immediately afterwards with no real space to merge.

Heading westbound, you get two 'straight ahead' lanes at the first set of lights, but again few wish to use the right-hand lane unless turning right towards the church. Some jump the queue by using the wrong side of the road to get into that outside lane, which is another reason why few use the outside lane with the tiny merge space in the opposite direction. Then you get two 'straight ahead' lanes at Tesco, where the outside lane can be used to pass traffic turning into the supermarket, but which isn't much use if everybody is going straight on because of another short merge.

If you ask me, they missed a trick by not making the outside lane continue into the right-turn filter for the town centre immediately after the dualled section ends. It seems crazy that two lanes merge into one before immediately opening up for the filter, because quite a lot of traffic does use that filter to turn into the town.

Keith wrote: A northern bypass seems a non starter due to the presence of the racecourse and the local topology. There is no southern option unless you go in for mass demolition.
As I pointed out earlier in the thread, when I was a pupil at Wyedean School (on the English side, in Sedbury) at the time of the construction of the new Wye Bridge and A48 Tutshill bypass, there was talk of the A48 following the railway line down the Welsh bank of the Wye to meet the M48 - then M4 - at the existing A466 junction.

I don't know how serious the plan was, or on what grounds it might have been rejected (if, indeed, it ever got as far as being proposed). It would, in my opinion, make all the difference though.

Keith wrote: So the only option is to fix the A48/A466 roundabout . In theory you could put the A466 on a flyover but I dont see that happening. I see from GSV that the desire route from the A466 to the A48 heading NE has been blocked off.
https://www.google.co.uk/maps/@51.63651 ... 6656?hl=en

Realistically I suspect that the best that could be expected is to install a Hamburger roundabout as was done at the A66/A171 junction here.
https://www.google.co.uk/maps/@54.57510 ... !1e3?hl=en

However this is a much busier junction than the A48/A466 so realistically all I expect is that the roundabout will be signalised.
I think focusing on the A48/A466 roundabout is a bit of a red herring, because I don't think that's where the real problem lies.

My father (who taught at the Kingsmark School in Chepstow) had a colleague who lived out towards Mynydd-bach. She described the Tesco as being on "the wrong side of the town", which it was for her, but which it wasn't for anybody travelling in from the Lydney direction.

The real problem, I think, is the location of the Tesco and the standard of the A48 which has to serve that store at the same time as serving through-traffic between the A48 in Gloucestershire and the M48 in South Wales.

booshank wrote:
Wed Oct 20, 2021 14:32
I use this to get to the Forest of Dean from time to time so I'm fairly familiar with the M48-A466-A48 route (but not so much with the other two main arms of that roundabout). The main problem seems to be the bottleneck that Chepstow forms on the A48. NE bound traffic builds up on the A48 through Chepstow, especially on the hill before the Wye bridge, and then backs up to the Highbeech roundabout and the whole thing gets clogged up once traffic from the M48 direction can't exit the roundabout towards Chepstow.
That does indeed appear to be crux of the whole issue, because of the location of the Tesco and the A48 serving it. And the problem is mirrored in the opposite direction, when the queues from the lights near Tesco can stretch all the way back along the A48 Tutshill bypass.

JohnnyMo wrote:
Wed Oct 20, 2021 14:56
That sounds like the phasing of the light as Mount Pleasant (Tesco) is wrong, I can't see how else a S2 thru a town will get congested as it leaves the town.
As described above, I think it's more to do with the lane provision through the lights, than the lights themselves.

JohnnyMo wrote:
Wed Oct 20, 2021 14:56
Alternative solution is extend the 30mph zone to Glostershire, which should increase the capacity on the bridge :coat:
They've already reduced it from NSL to 50 as far back as the B4228 turning east of Tutshill, and it mskes no difference what the limit is if you can only drive at walking pace!

Beardy5632 wrote:
Wed Oct 20, 2021 16:23
Those lights by Tesco have had phasing issues for years. If I ever need to head into or through Chepstow it can sometimes be quicker crossing the old Wye bridge and using the one way system to get to them as the A48 bridge can often queue if you catch it at the wrong time.
I don't know how old you are, but when I was a kid in St Briavels the old bridge was the way into Chepstow! Imagine what the queues were like then.....
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Re: End of the M48?

Post by JohnnyMo » Wed Nov 03, 2021 10:40

Owain wrote:
Wed Nov 03, 2021 09:23
...
KeithW wrote:
Wed Oct 20, 2021 12:12
When congestion occurs what is the cause ?

The traffic volumes dont seem that high frankly, I know of roundabouts that are much busier that cope tolerably well except at certain periods of the day when one road carries considerably more traffic than the other. From what I can see on GSV the roundabout does not seem to be signalised. The AADF on the A466 is around 20k so I can see that at peak getting into the traffic flow might be a problem. In an ideal world yes the A48 at Chepstow should have a bypass but where would it go ?
In my experience, the two sets of lights in close proximity near Tesco cause the bulk of the problem; or, rather, the poor lane provision at those lights. If you look on GSV, there is effectively only one lane in each direction, even though they are separated by a tiny dual carriageway.

Heading eastbound, you get a right-turn filter for Tesco and the railway station, which isn't really long enough considering how much traffic wants to turn in there. Then you get two 'straight ahead' lanes at the second set of lights, but few wish to line up in the outside lane because both lanes merge into one immediately afterwards with no real space to merge.

Heading westbound, you get two 'straight ahead' lanes at the first set of lights, but again few wish to use the right-hand lane unless turning right towards the church. Some jump the queue by using the wrong side of the road to get into that outside lane, which is another reason why few use the outside lane with the tiny merge space in the opposite direction. Then you get two 'straight ahead' lanes at Tesco, where the outside lane can be used to pass traffic turning into the supermarket, but which isn't much use if everybody is going straight on because of another short merge.

If you ask me, they missed a trick by not making the outside lane continue into the right-turn filter for the town centre immediately after the dualled section ends. It seems crazy that two lanes merge into one before immediately opening up for the filter, because quite a lot of traffic does use that filter to turn into the town.
...
JohnnyMo wrote:
Wed Oct 20, 2021 14:56
That sounds like the phasing of the light as Mount Pleasant (Tesco) is wrong, I can't see how else a S2 thru a town will get congested as it leaves the town.
As described above, I think it's more to do with the lane provision through the lights, than the lights themselves.

JohnnyMo wrote:
Wed Oct 20, 2021 14:56
Alternative solution is extend the 30mph zone to Glostershire, which should increase the capacity on the bridge :coat:
They've already reduced it from NSL to 50 as far back as the B4228 turning east of Tutshill, and it mskes no difference what the limit is if you can only drive at walking pace!
At what point does the A48 become free flowing, any why?


So the problem is those lights, Obviously the council has tried fixing then by adding an extra lane, adding more lane just will make the merge worse. I can't see Chepstow getting a new bypass.
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Re: End of the M48?

Post by Owain » Wed Nov 03, 2021 14:02

JohnnyMo wrote:
Wed Nov 03, 2021 10:40
So the problem is those lights, Obviously the council has tried fixing then by adding an extra lane, adding more lane just will make the merge worse. I can't see Chepstow getting a new bypass.
The lanes at the lights are exactly as they were when the road opened in 1988. The issues with them that I described above have therefore been there from the beginning (re. short merges and filters), even if the Tesco was not constructed until a few years later and has obviously made everything a whole lot worse.

My parents moved from Tutshill a decade ago, so I haven't had much cause to drive through Chepstow since then. But I can remember that eastbound traffic could queue all the way from Hardwick Hill down to those lights, while in the westbound direction taking a left-turn out of here would require somebody letting you out into the queue during peak periods.

In terms of traffic flowing freely, things would tend to improve as soon as you'd got past those lights, in both directions. It could still be slow up to the A48/A466 roundabout though, if busy.

There are still places where I'd question why anybody in their right mind would ever attempt to turn right out of a side road! During rush hour you'd have to be desperate to try it from here, and mad to attempt it here!!
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Re: End of the M48?

Post by JohnnyMo » Wed Nov 03, 2021 14:30

Owain wrote:
Wed Nov 03, 2021 14:02
JohnnyMo wrote:
Wed Nov 03, 2021 10:40
So the problem is those lights, Obviously the council has tried fixing then by adding an extra lane, adding more lane just will make the merge worse. I can't see Chepstow getting a new bypass.
The lanes at the lights are exactly as they were when the road opened in 1988. The issues with them that I described above have therefore been there from the beginning (re. short merges and filters), even if the Tesco was not constructed until a few years later and has obviously made everything a whole lot worse.

My parents moved from Tutshill a decade ago, so I haven't had much cause to drive through Chepstow since then. But I can remember that eastbound traffic could queue all the way from Hardwick Hill down to those lights, while in the westbound direction taking a left-turn out of here would require somebody letting you out into the queue during peak periods.

In terms of traffic flowing freely, things would tend to improve as soon as you'd got past those lights, in both directions. It could still be slow up to the A48/A466 roundabout though, if busy.

There are still places where I'd question why anybody in their right mind would ever attempt to turn right out of a side road! During rush hour you'd have to be desperate to try it from here, and mad to attempt it here!!
Thanks for that, not knowing the area just reading the thread. The first posts seemed to say M48 Jct 2 was congested -- which made no sense. It then transpired the congestion was at the A48/A446 roundabout which was backing up. Both KeithW and myself could see how that could be a problem. Peak flow from both the A446 & A48 towards the motorway without a balancing flow onto the A48(E) to stop the A446. Easily solved by making a signalled roundabout.

The it turned out the problem was traffic leaving the roundabout as the A48(E) thru Chepstow was backing up. Lights at Tesco causing a problem, no as the congestion extended well beyond that point to Tutshill.
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Re: End of the M48?

Post by Owain » Wed Nov 03, 2021 15:04

JohnnyMo wrote:
Wed Nov 03, 2021 14:30
Thanks for that, not knowing the area just reading the thread. The first posts seemed to say M48 Jct 2 was congested -- which made no sense. It then transpired the congestion was at the A48/A446 roundabout which was backing up. Both KeithW and myself could see how that could be a problem. Peak flow from both the A446 & A48 towards the motorway without a balancing flow onto the A48(E) to stop the A446. Easily solved by making a signalled roundabout.

The it turned out the problem was traffic leaving the roundabout as the A48(E) thru Chepstow was backing up. Lights at Tesco causing a problem, no as the congestion extended well beyond that point to Tutshill.
Not at all - as a child obsessed with cars and roads in the days before the internet and SABRE, I paid a lot of attention to the area in which I grew up!

In as much as I've ever seen the M48 J2 congested, it is evening rush traffic returning home from jobs in Bristol. I'm not sure that marking out two lanes on the M48 slip as both bound for A466 does much to help, because there is only one lane onto the A466 from the roundabout (it's S2+1 in the opposite direction at that point) and that can cause a conflict between the two lanes of traffic on the roundabout itself.

Even before the tolls disappeared, there was plenty of commuter traffic across the Severn Bridge. For the last few years of his career, my dad worked in Stroud, and I had teachers at my school who lived in the Bristol area. My mum worked in Cinderford, and there was even one who commuted to that school from Bristol (I can't imagine why they'd want to do that in the winter, given what the roads through the Forest could be like!).

What the tolls did do was deter people from Chepstow, the Wye Valley, and the Forest of Dean from shopping in Bristol; the enormous Cribbs Causeway retail park was only 20 minutes' drive, but because of the toll many people would prefer to shop in Gloucester or Cardiff (both 45 minutes).
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Isleworth1961
Member
Posts: 570
Joined: Thu Aug 30, 2012 14:15
Location: South Gloucestershire

Re: End of the M48?

Post by Isleworth1961 » Wed Nov 03, 2021 17:06

Owain wrote:
Wed Nov 03, 2021 15:04
JohnnyMo wrote:
Wed Nov 03, 2021 14:30
Thanks for that, not knowing the area just reading the thread. The first posts seemed to say M48 Jct 2 was congested -- which made no sense. It then transpired the congestion was at the A48/A446 roundabout which was backing up. Both KeithW and myself could see how that could be a problem. Peak flow from both the A446 & A48 towards the motorway without a balancing flow onto the A48(E) to stop the A446. Easily solved by making a signalled roundabout.

The it turned out the problem was traffic leaving the roundabout as the A48(E) thru Chepstow was backing up. Lights at Tesco causing a problem, no as the congestion extended well beyond that point to Tutshill.
Not at all - as a child obsessed with cars and roads in the days before the internet and SABRE, I paid a lot of attention to the area in which I grew up!

In as much as I've ever seen the M48 J2 congested, it is evening rush traffic returning home from jobs in Bristol. I'm not sure that marking out two lanes on the M48 slip as both bound for A466 does much to help, because there is only one lane onto the A466 from the roundabout (it's S2+1 in the opposite direction at that point) and that can cause a conflict between the two lanes of traffic on the roundabout itself.

Even before the tolls disappeared, there was plenty of commuter traffic across the Severn Bridge. For the last few years of his career, my dad worked in Stroud, and I had teachers at my school who lived in the Bristol area. My mum worked in Cinderford, and there was even one who commuted to that school from Bristol (I can't imagine why they'd want to do that in the winter, given what the roads through the Forest could be like!).

What the tolls did do was deter people from Chepstow, the Wye Valley, and the Forest of Dean from shopping in Bristol; the enormous Cribbs Causeway retail park was only 20 minutes' drive, but because of the toll many people would prefer to shop in Gloucester or Cardiff (both 45 minutes).
Junction 2 currently has the left hand lane coned off as the bridge on the roundabout is currently under repair, with the left lane over it also closed off. Huge queues now back up as far back as halfway across the Severn Bridge (well, that's as far as the one's I've seen went) at going home time.
The tolls also deterred lot of people from the Bristol side from going to the Forest of Dean and South Wales for a day out. I no longer have the pleasure of that smug feeling as I passed through the toll booth for free on my motorcycle...

mfmman
Member
Posts: 160
Joined: Sun Sep 12, 2010 19:12

Re: End of the M48?

Post by mfmman » Wed Nov 03, 2021 19:27

Owain wrote:
Wed Nov 03, 2021 09:23

One quirk of M48 J2 is that traffic exiting the motorway from the direction of the Severn/Wye Bridges tends to take the left-hand lane to turn right at the roundabout for the A466. This convention dates back to when the roundabout had only two arms other than the motorway slips; one for the large trading estate to the south of the motorway, and the other for the A466. As little traffic entered the trading estate, the vast majority of traffic used the left-hand lane for the A466, and the right-hand lane was largely wasted.
When originally built there wasn't even a left turn to the trading estate so both lanes were turning right (unless they went back on to the M4). I can't be exactly sure when the access road to the trading estate was built but I'd guess at 1986/7

mfmman
Member
Posts: 160
Joined: Sun Sep 12, 2010 19:12

Re: End of the M48?

Post by mfmman » Wed Nov 03, 2021 19:35

Isleworth1961 wrote:
Wed Nov 03, 2021 17:06
Owain wrote:
Wed Nov 03, 2021 15:04

What the tolls did do was deter people from Chepstow, the Wye Valley, and the Forest of Dean from shopping in Bristol; the enormous Cribbs Causeway retail park was only 20 minutes' drive, but because of the toll many people would prefer to shop in Gloucester or Cardiff (both 45 minutes).
Junction 2 currently has the left hand lane coned off as the bridge on the roundabout is currently under repair, with the left lane over it also closed off. Huge queues now back up as far back as halfway across the Severn Bridge (well, that's as far as the one's I've seen went) at going home time.
The tolls also deterred lot of people from the Bristol side from going to the Forest of Dean and South Wales for a day out. I no longer have the pleasure of that smug feeling as I passed through the toll booth for free on my motorcycle...
When small car derived vans (like an Astravan which was basically an estate without windows) got lumped in with much bigger vans up to 3.5 tons I think, the toll was double that of a car. 'Going round' became pretty appealing if you were only going to come off at Chepstow and head anywhere to the north/north west, although going through the 'cars only' lane and quickly throwing your money into the collection bucket might have been equally appealing to some I guess :?:

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