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Old October 4th, 2010, 01:04 AM   #1721
Fargo Wolf
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Originally Posted by ChrisZwolle View Post
... which is plain stupidity. What if there are roadworks, and the road is closed and the sign says "follow Springfield", but you have no idea where that is because you never look at the signs?

GPS is for dumbasses too lazy to prepare their journey. How many times don't you read about people end up in the wrong city with the same name, in a ditch because they followed GPS-orders too closely, or other stupid things?

What if you're driving on a road with frontage roads, and GPS thinks you're driving on the frontage road, and says "turn right here"? You could easily take an exit you don't want to take. I've seen this numerous times on my GPS, thats why I never rely on it. GPS software is full of errors, one-way streets that are the other way around, new roads that aren't opened yet, or are opened, but not on GPS.
Wholeheartedly seconded Chris. In fact, this past winter in the US state of Washington, a mother and her two kids were missing for nearly a week, because the sat nav indicated she turn onto a logging road. The fact that the road was NOT plowed, should have been a clue....
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Old October 4th, 2010, 01:25 AM   #1722
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Originally Posted by strandeed View Post
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Hardly - the elevated section is still 2x2, and always going to be unless everything along it is bulldozed, so removing the bus lane will do NOTHING to increase throughput on this road. All this will do is moving the jam closer to London, while coach passengers suffer more delays. A negative-sum decision on the whole.
Rubbish, throughput is automatically doubled
Err, strandeed, how is throughput increased? A pipe can only take as much as it's narrowest point - and all the bus lane does is extend the 2 lanes on the elevated section back to the junction before the road narrows.

Removing the bus lane gives you nothing more than moving the bottleneck closer to London, allowing more stacking capacity. If the queues due to the two-lane section interfere with non-London Heathrow traffic, then it's a good idea to get rid of it, but as far as I can see, that's the only benefit I can see with getting rid of it.

The bus lane was a sensible thing to do, short of spending a lot of money widening the viaduct - OK, the A312 doesn't take a third of traffic off the M4, but moving the lane drop to the junction makes for a smoother flow and a slight increase in capacity because of that. Having a bus lane makes a better use of resources, given a few vehicles can use it (especially given a lack of scheduled buses), than just hatching it out.

There were ideas for a P&R site at Boston Manor to make use of that third lane, but they worked out that you'd have a ton of traffic on the M4 driving to it (from all over the Thames Valley that are close to the motorway network), that there wasn't enough capacity on the Piccadilly line (even before the Heathrow extension from Hounslow, when the scheme was mooted in the early 70s) either.
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Old October 4th, 2010, 09:56 AM   #1723
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Removing the bus lane gives you nothing more than moving the bottleneck closer to London, allowing more stacking capacity. If the queues due to the two-lane section interfere with non-London Heathrow traffic, then it's a good idea to get rid of it, but as far as I can see, that's the only benefit I can see with getting rid of it.
I think this has to be considered. Buffering traffic may not solve a traffic jam, but it could be a solution to make sure the traffic jam does not interfere with other traffic not bound for central London, but one of the earlier exits, Heathrow Airport or even M25.
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Old October 4th, 2010, 10:04 AM   #1724
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Err, strandeed, how is throughput increased? A pipe can only take as much as it's narrowest point - and all the bus lane does is extend the 2 lanes on the elevated section back to the junction before the road narrows.

Removing the bus lane gives you nothing more than moving the bottleneck closer to London, allowing more stacking capacity. If the queues due to the two-lane section interfere with non-London Heathrow traffic, then it's a good idea to get rid of it, but as far as I can see, that's the only benefit I can see with getting rid of it.

The bus lane was a sensible thing to do, short of spending a lot of money widening the viaduct - OK, the A312 doesn't take a third of traffic off the M4, but moving the lane drop to the junction makes for a smoother flow and a slight increase in capacity because of that. Having a bus lane makes a better use of resources, given a few vehicles can use it (especially given a lack of scheduled buses), than just hatching it out.

There were ideas for a P&R site at Boston Manor to make use of that third lane, but they worked out that you'd have a ton of traffic on the M4 driving to it (from all over the Thames Valley that are close to the motorway network), that there wasn't enough capacity on the Piccadilly line (even before the Heathrow extension from Hounslow, when the scheme was mooted in the early 70s) either.
You are correct that the choke point limits the road, however the bus lane did very little to help ease congestion, considering that most passenger will take the train or drive from heathrow.

Perhaps a double-deck solution would help in this case if land is an issue, when funds permit.
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Old October 4th, 2010, 03:49 PM   #1725
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Originally Posted by ChrisZwolle View Post
I think this has to be considered. Buffering traffic may not solve a traffic jam, but it could be a solution to make sure the traffic jam does not interfere with other traffic not bound for central London, but one of the earlier exits, Heathrow Airport or even M25.
Yes, indeed, hence I mentioned it.

However the reason it's going is purely politicking - loads of people give strandeed-type arguments of "no buses use it" and fail to see the reasons why it was actually put in and how removing it won't reduce journey times into Central London, and would probably increase them by non-significant 20 seconds or something. It's a hated part of "the war on motorists": exhibit A on how they favour buses over cars, when actually it's probably the most car-friendly bus lane in the country (and most pointless one for buses).

If the queue is reaching Heathrow, then absolutely get rid of it, but get rid of it to move the bottleneck forward to allow more space for cars to queue, not for political points, not because no buses use it.
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You are correct that the choke point limits the road, however the bus lane did very little to help ease congestion, considering that most passenger will take the train or drive from heathrow.
Actually, many of those who don't take the train to get to/from Heathrow, and head inwards on the M4, take coaches or taxis, which can (and do) use the lane. However, you forget the point of the bus lane wasn't to serve buses, or get people onto them or anything like that, but to move the bottleneck to a junction, allowing smoother flowing traffic. It does not ease congestion or shorten journey times (much), because the bottleneck still exists - what it does is smooths the flow. It adds a smidge more to the capacity, as you don't have the problem of the merge - perhaps as much as an extra car a minute in peak times, which is nothing given how many cars use the elevated section.

You want rid of it as you don't understand it, you think it's about buses, when it's not - it's a bus lane simply as hatching was felt to be a bit of a waste - may as well let a few hundred vpd use the space, rather than zero.
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Perhaps a double-deck solution would help in this case if land is an issue, when funds permit.
The A4 under the elevated section is 3+3, so you could have the M4 as 3+3 - it's probably more aesthetically pleasing than a third level. Tunnelling would be the least controversial decision, although costly (but so would be the other two)

Anyway, there's barely the capacity to deal with the two lanes of M4 emptying onto the A4 at Chiswick as it is, so all a very-expensive widening scheme would do is just give more stacking space for the bottleneck where the motorway ends (currently masked by the narrowing at junction 3). It's not worth the huge cost at all.

As I said above, the only rational reason to remove the bus lane is if the jam is interfering with non-London Heathrow traffic.
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Old October 4th, 2010, 06:11 PM   #1726
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.

One more thing, give us €1.50 to the £ and we'll swop to the Euro.
That's a predatory rate against Euro countries; Why should they be forced to pay that kind of rate? A weak pound is good for the UK. If anything, the GBP is over-valued against the EUR.

It should be 1 GBP = 1 EUR.
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Old October 4th, 2010, 08:42 PM   #1727
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Good news. I've never seen the point of it as rail is a much quicker way of getting into London from Heathrow and all the lane does is funnel three lanes' worth of traffic into two, especially bad when the elevated section in Brentford is already 2x2!
Absolutely, with the Tube, Heathrow Express and other rail services, I don't know anyone in their right mind who would leave LHR by bus, especially if your carrying lots of luggage.
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Old October 4th, 2010, 08:56 PM   #1728
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Let's hope this is a sign that the anti-roads mania that has gripped Britain for the last 15-20 years is fading.

There's plenty of space for at least 2x4 double decker , especially if hard shoulders are sacrificed for extra lanes. One could have 4 lanes each on two decks with local traffic below at ground level and it would be no wider than the present elevated section - no bulldozing necessary.

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Old October 4th, 2010, 09:11 PM   #1729
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Is that Johannesburg?
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Old October 4th, 2010, 09:53 PM   #1730
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Absolutely, with the Tube, Heathrow Express and other rail services, I don't know anyone in their right mind who would leave LHR by bus, especially if your carrying lots of luggage.
But the Bus Lane isn't for buses (which don't run on it at all) - how many times to have to say that!

The bus lane is a pro-car improvement that also allows taxis and coaches to overtake some of the jam caused by the lack of capacity at the end of the M4.

BTW, many people leave LHR by bus every day - the workers! There's bus services heading out in many directions - and one would bet that quite a few people near bus stops would use it to get to the airport for a flight, as it is a lot cheaper than a taxi if there's just one of you.
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Let's hope this is a sign that the anti-roads mania that has gripped Britain for the last 15-20 years is fading.
I'd say that isn't - I'd even call removing the M4 Bus Lane, other than for the one legit reason I gave (that it causes queueing traffic from the inevitable lane reduction to get back to Heathrow), anti-car.
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There's plenty of space for at least 2x4 double decker , especially if hard shoulders are sacrificed for extra lanes. One could have 4 lanes each on two decks with local traffic below at ground level and it would be no wider than the present elevated section - no bulldozing necessary.
Just a lot of unhappy people in the buildings next to it that will have lost their light, plus nowhere for the cars to go at the London end! Oh, and demolishing the existing road and modifying ground level, unless you have the middle level as 2+2 - the supports are in the middle, not on the edge.

There are also no hardshoulders on the M4 there at the moment - if there were, we wouldn't be having this discussion, as rather than extending the two-lane section to junction 3, they would be the 3-lane section extended along the hard shoulder to junction 2. </FACEPALM>

Completely and utterly pointless, and very expensive! I'd say doing that would be anti-car, given you'd create a huge backlash against road building from it (think Twyford Down and Newbury bypass).
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Old October 4th, 2010, 10:06 PM   #1731
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Absolutely, with the Tube, Heathrow Express and other rail services, I don't know anyone in their right mind who would leave LHR by bus, especially if your carrying lots of luggage.
Because I have to

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Is that Johannesburg?
I guess so; the cars have Gauteng registrations
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Old October 4th, 2010, 10:11 PM   #1732
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I can understand workers using the buses but I doubt the majority of passengers would think of buses as the most convenient transportation.
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Old October 4th, 2010, 10:14 PM   #1733
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From where I live, it's the only way. Both my parents work there too anyway.
At least the buses are free inside the airport.

That is a really badly structured paragragh.
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Old October 5th, 2010, 01:07 AM   #1734
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Yes, indeed, hence I mentioned it.

Anyway, there's barely the capacity to deal with the two lanes of M4 emptying onto the A4 at Chiswick as it is, so all a very-expensive widening scheme would do is just give more stacking space for the bottleneck where the motorway ends (currently masked by the narrowing at junction 3). It's not worth the huge cost at all.

As I said above, the only rational reason to remove the bus lane is if the jam is interfering with non-London Heathrow traffic.

Another possible benefit of the bus lane is that once the road starts to become congested at the two lane section, it gives some drivers (depending on destination) the option of leaving at J3 and finding an alternative route because they are given more advanced warning of the congestion to come. This also benefits those continuing on the M4 by slightly reducing traffic.

In my experience there's nothing more frustrating than suddenly finding traffic at a standstill when you've just breezed past a junction you happily could've used, this will happen a lot more with 3 lanes heading into the bottleneck
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Old October 5th, 2010, 11:52 AM   #1735
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There is probably a coach going into London on the M4 every 5 minutes, given the number of major towns and cities on this corridor (Swindon, Bath, Bristol and Cardiff to name just a few) so even as a bonus point, the number of coach passengers benefiting from the bus lane isn't negligible.
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Old October 5th, 2010, 01:57 PM   #1736
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Coaches from the M3 corridor (Bournemouth, Southampton, Portsmouth, etc) go to Victoria via Heathrow, and I imagine other buses do as well (or at least some of them).
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Old October 5th, 2010, 03:15 PM   #1737
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Maybe it would be easier to install a new slip road where the road has to narrow before the Chiswick Flyover, so that it funnels some traffic onto the A4 under the elevated section earlier, as not doubt there will be some traffic trying to get to the North and South Circs.
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Old October 6th, 2010, 10:21 PM   #1738
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yeah, we could really do with the north and south circulars being a proper inner motorway ring rather than the mish-mash of local dual-carriageways they are.

If all the radiating motorways entering the London area from around the country then terminated at that inner ring rather than at the M25 or just beyond like they do now it would make a big difference I think.
I agree with most of your post, but I disagree with the part where you say that north and south circulars are a "mish-mash of local dual-carriageways". I think that this statement depicts the situation in London as better than it really is. Most of south circular looks like this:



So London doesn't really have a south circular. It is just a mish-mash of local high-streets and narrow 1+1 roads with cars parked on each side and a single level junction every 20 meters. The north circular is much better, however, it also has its traffic blackspots (I spent an hour on it on Monday) and single level junctions that are constantly clogged. London is in a desperate need for an inner ring but it hasn't even yet built 50% of it. The situation with traffic in the "circulars" is tragic.

I spoke to a guy from TfL and their opinion is that "it is impossible to improve the situation with roads in London and public transport is the priority" and "the more roads you build the more they will clog up". I find that opinion to be ridiculous and insane. Too bad I forgot to ask what their arguments were against expanding the North Circular in places where surrounding houses have already been bought out for that particular purpose (now squatters live there).
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Old October 7th, 2010, 09:18 AM   #1739
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I spoke to a guy from TfL and their opinion is that "it is impossible to improve the situation with roads in London and public transport is the priority" and "the more roads you build the more they will clog up". I find that opinion to be ridiculous and insane
To some extent, there is a truth in there. Because of decades of neglect of the road network, the actual traffic demand is much higher than a few improvements can handle. However, this is not an excuse not to improve the road system at all.
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Old October 7th, 2010, 11:01 AM   #1740
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I spoke to a guy from TfL and their opinion is that "it is impossible to improve the situation with roads in London and public transport is the priority" and "the more roads you build the more they will clog up". I find that opinion to be ridiculous and insane.
You may find it ridiculous & insane, but it's still true! This chap knew what he was talking about. There is massive suppressed demand on London's roads that could only be fully catered for by building an 8 to 10 lane North/South Circular (something along the lines of Paris' Peripherique, I suppose) and an extension of the motorway radials to meet the new road. We all know that is never going to happen. So there is no point in delivering a half-arsed effort that, as your man at TfL says, will simply clog up on day one.

I, for one, think TfL have it more or less right here. In a contiguous urban area of possibly 10 million people (?), the idea that there should be a 'right' to cart a metal box around with you for your own personal use - and that transport policy should bend over backwards to enable this - is absurd. I am reasonably sure that in as little as 50 years from now, mass travel by car (or equivalent) within large cities will very much be a thing of the past. And at that point, we may well be very grateful that we haven't carved up the urban fabric of one of the western world's greatest cities in order to accommodate an obsolete form of travel.
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