route:oxford
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removing one bottleneck will result in a bottleneck elsewhere
If you are prepared to guarantee that this is the case...
Makes the £500m upgrade of Reading look rather silly.
removing one bottleneck will result in a bottleneck elsewhere
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?
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?)
If you are prepared to guarantee that this is the case...
Makes the £500m upgrade of Reading look rather silly.
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.
Basically people drive because the railways are rubbish (well, underfunded). I'm not saying it, science is!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.
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.
No, because the Brynglas Tunnels have been a bottleneck ever since they opened 30+ years ago. The 2nd Severn Crossing has made no difference.
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.
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.
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.
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.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?)
Once again, I agree with that.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.
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?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 )
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).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 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.
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.
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.
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?
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.
Good spot, but the observation that traffic fills roads isn't obviated by that. More roads just means more traffic; it does nothing to relieve congestion.Not much relevance to the particular case in question?
More roads just means more traffic; it does nothing to relieve congestion.
See also - https://en.wikipedia.org/wiki/Induced_demand
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.
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
Er, no I didn't say I did. But neither do I ignore those costs when doing comparisons.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...
On any train booking website under "advance fares".And would you be so kind to show me where these "cheaper fares" are?
More roads just means more traffic; it does nothing to relieve congestion
...and more railways just creates more congestion on the rails, so there's no point in trying to improve any rail bottlenecks?
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!.
...and more railways just creates more congestion on the rails, so there's no point in trying to improve any rail bottlenecks?