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What effect could improved rail services have on M4 congestion?

What effect could improved rail services have on M4 congestion?

  • None or negligible - need to build a second M4

    Votes: 18 42.9%
  • Slight, but we still need a full new dual-carriageway

    Votes: 14 33.3%
  • Enough that a new dual-carriageway from steelworks road to M4 jun. 28/29

    Votes: 4 9.5%
  • Enough that we just need to upgrade the A48 a little bit

    Votes: 6 14.3%

  • Total voters
    42
  • Poll closed .
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Bald Rick

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Diverse maybe, but are there any major entry/exit points? For example, is a large portion of the traffic using the M4 for a long distance, having joined west of Port Talbot and staying on the M4 until England? Or is there a large flow to Swansea from England?

I would imagine (or hope?) that the WG have done some traffic surveys to show where traffic joins / leaves the M4 in the SE Wales area to inform this.

Whenever I use the section in question (admittedly about twice a year, always at weekends) there is congestion. Not once has it been caused by an accident, just sheer weight of traffic. It's not unlike the congestion that used to happen on the M4 at the Severn Bridge before the SSC was built. That congestion has now been eradicated, by and large.

Nevertheless, it is a lot of cash. But I really don't know what rail service improvements would help take that much traffic off the M4 (c25% reduction in peak time?)
 

DynamicSpirit

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Nevertheless, it is a lot of cash. But I really don't know what rail service improvements would help take that much traffic off the M4 (c25% reduction in peak time?)

I'm not familiar with the area, but looking at the map of where the motorway goes I'm inclined to agree that it's hard to see any obvious possible rail improvements that would be likely to remove significant traffic from that bottleneck.

However I would still maintain that - unless there are some really unusual local circumstances I don't know about - building a new road along the lines proposed is almost certainly a mistake. I know it's very frustrating for people caught in bottlenecks, and it's very easy to want a new road to speed journeys up. But you can virtually guarantee that in the long term harm any new relief road will do (in terms of things like encouraging mode-shift to cars for other journeys and in the process probably creating bottlenecks elsewhere) will far outweigh the immediate benefit.

Far better to spend the proposed money on generally improving public transport in the area, which will on balance make life better for significant numbers of people living around Newport. (An obvious one would be to get on with the direct Ebbw Vale-Newport rail link).

(Unfortunate there's no option corresponding to that opinion in the poll, so I can't really vote ;) )
 

Llanigraham

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You are making the presumption that most of the traffic using the Brynglas Tunnels is local, whereas I would expect most of it to be the opposite. Typically those from Cardiff and points west heading towards London, Bristol and the Midlands.
Most "local" traffic is heading in a north-south direction, not West-East
 

andykn

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If you are prepared to guarantee that this is the case...

Makes the £500m upgrade of Reading look rather silly.

But the difference is that rail bottlenecks can be removed, the primary road ones can't without demolishing the destination thus removing the need for the bottleneck to be removed in the first place.

Imagine how much of London you'd need to knock down to provide the roads and parking for all the people who commute by rail every day. Those bottlenecks can be overcome at railheads but not roads.
 

Bald Rick

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However I would still maintain that - unless there are some really unusual local circumstances I don't know about - building a new road along the lines proposed is almost certainly a mistake. I know it's very frustrating for people caught in bottlenecks, and it's very easy to want a new road to speed journeys up. But you can virtually guarantee that in the long term harm any new relief road will do (in terms of things like encouraging mode-shift to cars for other journeys and in the process probably creating bottlenecks elsewhere) will far outweigh the immediate benefit.

Using that logic though, all the bypasses and motorways that have been built have been bad for us. And I don't think that's the case.

I do think it is the case that in some cases, new roads are warranted, and this is one of them. Equally, there are many cases where new railways are warranted, and we should build them too.
 

orpine

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Folks may be interested in this:
http://en.wikipedia.org/wiki/Downs-Thomson_paradox

the equilibrium speed of car traffic on the road network is determined by the average door-to-door speed of equivalent journeys by (rail-based or otherwise segregated) public transport.
Basically people drive because the railways are rubbish (well, underfunded). I'm not saying it, science is! :)

There is also:
http://en.wikipedia.org/wiki/Lewis–Mogridge_Position
the more roads are built, the more traffic there is to fill these roads. Speed gains from some new roads can disappear within months if not weeks. Sometimes new roads do help to reduce traffic jams, but in most cases the congestion is only shifted to another junction.

Someone needs to show the assembly members the research.
 

HSTEd

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But having more travel tends to be good for the economy.

If people were simply not permitted to travel more than a few miles from their registered address without a permit then there would be no need for a motorway network as it currently exists.
 

DynamicSpirit

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No, because the Brynglas Tunnels have been a bottleneck ever since they opened 30+ years ago. The 2nd Severn Crossing has made no difference.

I would be extremely surprised if it made no difference at all. That would only be possible if *no* new traffic at all travelling as far as Newport was induced onto the M4 by the removal of the bottleneck at the Severn crossing. That really does not seem credible. However, I realize we are all arguing here on the basis of plausibility/perception without any firm statistics, and it would be better if we did have some.
--- old post above --- --- new post below ---
Using that logic though, all the bypasses and motorways that have been built have been bad for us. And I don't think that's the case.

Well, Newport does already have a by-pass, so pedantically the logic would only apply to building 2nd by-passes around towns ;) (In case it's not clear, that was partly a joke, the logic is obviously more complex than that in reality). But there is an interesting point there.

When you are thinking about the usefulness of roads that have long-since already been built, it's easy to fall into a trap: Whenever a road is built, over the next few years many people in the area will automatically adjust their habits - where they live, where they work, etc. in such a way that they become dependant on the new road (And yes, the same thing will happen with new railways, new cycle paths, etc. etc.). So with hindsight you will look at any road and say, 'Clearly, building this road was absolutely essential - look how many people depended on it'.

But of course, if the road hadn't been built, then that adjustment of habits wouldn't have taken place, and on the whole people would not have become dependant on it. On the whole those people would very likely still have been as happy and as prosperous without the new road - just perhaps living in different locations or shopping in different locations, etc. So the logic fails.

Now sure, that's not to say that no new roads should ever be built. Each one needs to be evaluated on its merits - but you do need to take account of the wider long term effects that a road being there will have, and say, are the benefits sufficient to outweigh the long term disadvantages the road will induce. I would say that there are many roads in the UK where, if the money spent on building them had been spent on walking/cycling/public transport facilities instead, then the net benefits would have been far greater. We would have been just as prosperous, but living with fewer traffic jams, and more sustainable, and less frustrating, commuting habits. But of course we can't see that because the roads, by virtue of having already been built, have already become essential!

And in the case under discussion. But when we are talking about a 2nd by-pass around a town that already has a substantial road network, but where the rail network is clearly inadequate, all to clear one single bottleneck, that definitely looks to me like wrong priorities and lack of long term thinking. History (and common sense) does seem to show that relieving single bottlenecks on roads in this way just creates other bottlenecks in different places.
--- old post above --- --- new post below ---
There are many journeys made all over the UK where it is not feasible to use public transport let alone the train. We should not be making it harder for people to use their cars in order to force them to use the train. Individuals should have a choice as to which mode of transport they choose to use.

If I were you I'd be careful about bringing the choice argument in to support the car. There are far more journeys in the UK where people are 'forced' to use cars thanks to decades of car-centric transport policies then there are places where the reverse is true! Newport is a massive town with *one* single railway station and close to zero local rail commuter network (but lots of roads you can drive on). So in that particular town, I'd suggest building more railways instead of building more roads would win any argument based on providing choice-of-transport hands down.
 
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pablo

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Folks may be interested in this:
http://en.wikipedia.org/wiki/Downs-Thomson_paradox


Basically people drive because the railways are rubbish (well, underfunded). I'm not saying it, science is! :)

There is also:
http://en.wikipedia.org/wiki/Lewis–Mogridge_Position


Someone needs to show the assembly members the research.

Like this quote: "However, according to Anthony Downs this link between average speeds on public transport and private transport "only applies to regions in which the vast majority of peak-hour commuting is done on rapid transit systems with separate rights of way. Central London is an example, since in 2001 around 85 percent of all morning peak-period commuters into that area used public transit (including 77 percent on separate rights of way) and only 11 percent used private cars. When peak-hour travel equilibrium has been reached between the subway system and the major commuting roads, then the travel time required for any given trip is roughly equal on both modes.""

Not much relevance to the particular case in question?
 

Rhydgaled

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Whenever I use the section in question (admittedly about twice a year, always at weekends) there is congestion. Not once has it been caused by an accident, just sheer weight of traffic. It's not unlike the congestion that used to happen on the M4 at the Severn Bridge before the SSC was built. That congestion has now been eradicated, by and large.

Nevertheless, it is a lot of cash. But I really don't know what rail service improvements would help take that much traffic off the M4 (c25% reduction in peak time?)
Things are always going to be busier a peak times aren't they. How much off-peak congestion on the M4 is there? If you build enough new road capacity to eliminate peak-time congestion, there will be an awful lot of space on the road off-peak which is likely to lead to more traffic using that space, rather than using public transport.

However I would still maintain that - unless there are some really unusual local circumstances I don't know about - building a new road along the lines proposed is almost certainly a mistake. I know it's very frustrating for people caught in bottlenecks, and it's very easy to want a new road to speed journeys up. But you can virtually guarantee that in the long term harm any new relief road will do (in terms of things like encouraging mode-shift to cars for other journeys and in the process probably creating bottlenecks elsewhere) will far outweigh the immediate benefit.
Once again, I agree with that.

Rather than just presenting a wall of opposition to WAG's consultation though I would like to propose something smaller and cheaper which would reduce the frustration in the worst suituations (ie. when one of the tunnels is shut) while minimising the negative modal shift building new roads is likely to cause.

Far better to spend the proposed money on generally improving public transport in the area, which will on balance make life better for significant numbers of people living around Newport. (An obvious one would be to get on with the direct Ebbw Vale-Newport rail link).

(Unfortunate there's no option corresponding to that opinion in the poll, so I can't really vote ;) )
Well, if you think Ebbw Vale - Newport services would reduce M4 congestion and hence the need for road enhancments, maybe that would fit one of the poll options?

Folks may be interested in this:
http://en.wikipedia.org/wiki/Downs-Thomson_paradox

Basically people drive because the railways are rubbish (well, underfunded). I'm not saying it, science is! :)
So speed is of the essance? Would more fast rail services be the answer? (that's actually the key element of the proposal I alluded to in my OP, but I'm not sure if it really would make any noticeable difference).
 

DavidBrown

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There are far more journeys in the UK where people are 'forced' to use cars thanks to decades of car-centric transport policies then there are places where the reverse is true! Newport is a massive town with *one* single railway station and close to zero local rail commuter network (but lots of roads you can drive on). So in that particular town, I'd suggest building more railways instead of building more roads would win any argument based on providing choice-of-transport hands down.

There's been a lot said in this thread that winds me up big time, but this is a very valid and very well made point.

If we look at the three main destinations for M4 traffic, we have;
Newport - 1 railway station
Cardiff - 20 stations
Swansea - 2 stations

Only Cardiff can ever dream of having substantial amounts of potential road traffic using its trains instead. For Swansea and Newport, there is simply no option other than the car. Whilst I don't visit any of those places too often, me and a friend are going to Swansea this weekend. Here's my choice, from Ilfracombe.

Car - A361, M5, M49, M4, A483. 176 miles in 3 hours 11 mins.
About £60 in fuel (return) plus £6.30 for the Severn Bridge. So £33 each.

Public Transport - 10 minute walk to bus stop.
1 hour bus journey to Barnstaple Railway Station (£4)
5 hour train journey (changing at Exeter St Davids and Bristol Parkway) (£75 return each)
15 minute taxi ride from Swansea station to destination (~£10)
So that's nearly 6.5 hours and about £82 each. i.e. Twice as long and 2.5 times more expensive. Why on earth would I not drive?

In comparison, if I wanted to go to Exeter (starting at Barnstaple - the bus is NOT an option - ever), both the car and the train would take around an hour, but the train would cost less (especially if I need city centre parking), and given that Exeter has 7 stations with 3 more proposed, there's not many areas of the city that aren't within walking distance of a station. In that case, why would I drive?

But even if Swansea has 10 stations served by trains every 15 minutes, the cost and time of long-distance travel is a massive put-off, and it's something that won't be sorted out with investment - ever. The M4 is the ONLY option for the vast majority of people using it, and will always remain so. That's why a new M4 is desperately needed.

Investment in railways can help massively with town and city centre congestion - like I say, I never have reason to drive into Exeter City Centre now. But the train will simply never be a realistic alternative to the car for any lengthy distance, and that's why investment is needed in local railways, and long-distance roads (i.e. motorways). Then you get the best of both worlds.
 

HowardGWR

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My thinking behind the topic was more what sort of rail service improvements could help, and how much they would help. Those service improvements may or may not require infrastructure enhancements, but this thread's more about the level of service needed, and perhaps the road infrastructure needed.

I am sorry, I did not realise that was your purpose when I suggested this was in the wrong section. I think that the notion that one could deal with the problem through extra train services will not wash, without discouraging people using the alternative car based travel in some way (traffic jams help!).

Nobody has come up with an analysis of origin and destination of M4 motorway travellers, or indeed of those using other roads in the area. Until one has that detailed analysis, no discussion of what modal shift to rail could be brought about is possible. I can be certain that most traffic on that stretch is local to South Wales because most traffic using our motorways is similarly locally orientated.

What is termed strategic car traffic (thus excluding freight for which the motorways were originally intended, not commuters) forms a small part of motorway traffic.

So without the data, I would be pretty confident that the opportunity for modal shift around Newport would be present, and I would also be confident that such modal shift would deliver carbon emission benefits. That's because it's the same story everywhere. Why otherwise are the worst regular jams always at 'going to work' or 'coming from work' time? It would mean many people would no longer be able to get in their car in the driveway, switch the stereo (etc) on and step out at the workplace with a few yards walk to the office.

But the present strategic traffic on the M4 around Newport would be flowing beautifully!

Find a local Welsh politician to support that (hah!). It's not even supported by some on here! :(
 
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DynamicSpirit

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Rather than just presenting a wall of opposition to WAG's consultation though I would like to propose something smaller and cheaper which would reduce the frustration in the worst suituations (ie. when one of the tunnels is shut) while minimising the negative modal shift building new roads is likely to cause.

How expensive would it be to simply build a 3rd tunnel alongside the existing tunnels? Then have the middle tunnel able to operate in either direction (but obviously, only one direction at a time) so it can ease whichever direction flow is heaviest in at any given time?

Well, if you think Ebbw Vale - Newport services would reduce M4 congestion and hence the need for road enhancments, maybe that would fit one of the poll options?

I think it would have a small impact - because some of the people along the M4 will be heading to places along the Ebbw Vale line, and some of those may find a direct Newport connection makes rail better for them. But I imagine it would be very marginal - not remotely enough to satisfy those who are calling for something to be done about the bottleneck.
 

HowardGWR

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Investment in railways can help massively with town and city centre congestion - like I say, I never have reason to drive into Exeter City Centre now. But the train will simply never be a realistic alternative to the car for any lengthy distance, and that's why investment is needed in local railways, and long-distance roads (i.e. motorways). Then you get the best of both worlds.

Your journey past Newport is a long distance one. See my post as I have opined that most congestion on the M4 will be caused by local traffic. If that largely came off the motorway there, you would be able to sail through Newport without hold up. But without the O / D data we would not know where to put the alternatives. I agree with you completely by the way. For the leisure traveller (which I could regard as 'strategic' because you will be spending money in West Wales) you cannot afford the fares, as a businessman could.
--- old post above --- --- new post below ---
@Rhydgaled

I hope you can see now why some of us could not possibly vote for any option you have provided. There isn't a non-road building one.
 

pablo

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These economic theories are all well and good. If you want to believe them, then.....

The way I see it there must be a finite limit to road traffic. Peeps don't want to spend all their time travelling around. It's like the company car driver that braggs about doing 70 thou a year. I ask him when, if ever, he does some work! So, the more roads get built the less the increase in traffic until equilibrium is reached?
And, as for covering the country in concrete? What piffle. If you ever fly low-level over this country, you see just how little land roads and railways take up. The country is mainly very unproductive greenery.
The only place in danger of concrete coverage is the section of the M25 west of Heathrow; 14 contiguous lanes. :p
 

andykn

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There's been a lot said in this thread that winds me up big time, but this is a very valid and very well made point.

If we look at the three main destinations for M4 traffic, we have;
Newport - 1 railway station
Cardiff - 20 stations
Swansea - 2 stations

Only Cardiff can ever dream of having substantial amounts of potential road traffic using its trains instead. For Swansea and Newport, there is simply no option other than the car. Whilst I don't visit any of those places too often, me and a friend are going to Swansea this weekend. Here's my choice, from Ilfracombe.

Car - A361, M5, M49, M4, A483. 176 miles in 3 hours 11 mins.
About £60 in fuel (return) plus £6.30 for the Severn Bridge. So £33 each.

No. You're ignoring all the other per mile costs of motoring, tyres, brakes, clutch etc. all wear according to the number of miles you do and add significant costs to each and every journey you make.

And you could get the train cheaper if you booked the train tickets when you planned the trip.
 
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DavidBrown

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No. You're ignoring all the other per mile costs of motoring, tyres, brakes, clutch etc. all wear according to the number of miles you do and add significant costs to each and every journey you make.

And you could get the train cheaper if you booked the train tickets when you planned the trip.

Wow - you go through £100 worth of brakes, tyres, clutch etc on a 350 mile round trip? Think there might be something wrong with your car, mate...

And would you be so kind to show me where these "cheaper fares" are?
 

HSTEd

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Motorway driving can easily reduce the wear of brakes and clutch to almost nothing.
 

HowardGWR

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The below link is to the recent WelTAG appraisal report for the project. I had a quick look, and the case for the M4 (in terms of indicating who will benefit etc) seems to have been done in previous studies. It may be in the previous work there is more detailed information on the origins/destinations of users?

http://www.m4cem.com/downloads/reports/Issue%20M4%20Corridor%20Around%20Newport%20WelTAG%20Appraisal%20Report%20Stage%201%20(Strategy%20Level).pdf

Thanks for the link,

This is in the opening sentences.

"The main road network in South Wales experiences traffic congestion during peak periods. This is particularly the case on the M4 motorway and on the approaches to Swansea, Cardiff and Newport. This results in unreliable journey times, which impacts on the ability of individuals to take up job opportunities and discourages investment from high value businesses. Transport congestion also has environmental impacts affecting local communities. "

So, they admit the problems are caused by local commuters. They then think that you can only hope to get a job if you have a car.

This proves my point that they are looking no further than their nose and are accepting the environmental outlook of the eighties 'the car economy'.

Elsewhere on the other section I read that Lancs CC has ruled out an Ormskirk bypass because 'most of the traffic is local'.

I think Welsh environmental activists should get on the case and demand the O /D studies I was talking about with a full explanation of alternative solutions. I hope you know a few Rhydgaled!. :D
 

andykn

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Wow - you go through £100 worth of brakes, tyres, clutch etc on a 350 mile round trip? Think there might be something wrong with your car, mate...
Er, no I didn't say I did. But neither do I ignore those costs when doing comparisons.
And would you be so kind to show me where these "cheaper fares" are?
On any train booking website under "advance fares".
 

pablo

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As a rule of thumb, I use twice the petrol cost for the marginal cost of using a car. On average, that reasonably covers all the other costs mentioned above that some peeps find hard to credit. But they are true and you see it if you keep proper accounts.
 

DynamicSpirit

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...and more railways just creates more congestion on the rails, so there's no point in trying to improve any rail bottlenecks?

I believe I already answered that point in post #10 of this thread.

There is another possible difference beyond the points I made in that post: Because of many people's reluctance to change trains, significant additional usage of rail services is relatively more likely to be confined those services that have directly benefitted from the relieved bottleneck. In contrast, for cars there are no changes involved no matter where you drive to, hence more people will, having taken advantage of the relieved bottleneck to make more journeys along the upgraded/new road, then continue their new journeys onto other roads that have not been upgraded, have no additional capacity, and therefore have the potential to become new bottlenecks.
--- old post above --- --- new post below ---
I think Welsh environmental activists should get on the case and demand the O /D studies I was talking about with a full explanation of alternative solutions. I hope you know a few Rhydgaled!. :D

I'm not entirely certain (not looked at the issue in enough detail) but there may be some mileage in comparing the Welsh Government's stance on the new Newport by-pass with what's happening with the Wrexham redoubling, where initial commitments to upgrade rail infrastructure to relieve a bottleneck appear to now be being followed up with considerable backtracking (so far as I can tell from the discussions of that issue on railforums).
 
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al78

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...and more railways just creates more congestion on the rails, so there's no point in trying to improve any rail bottlenecks?

There are environmental and social advantages to encouraging people to use public transport rather than drive, whereas the reverse is not true, hence the comparison doesn't work.
 
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