SW M25 Relief

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Peter Freeman
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SW M25 Relief

Post by Peter Freeman »

M25, England's most congested motorway, has two hotspots: Dartford Crossing and J10-16. Dartford has its relief in view - the proposed LTC. J10-16 is not quite without options, but meanwhile I wonder whether better exploitation of these alternatives would help:

1. J12-15 relief by improving A322/A329(M) as a route to reach M4 via M3.
2. J15-16 relief by improving A404/A404(M) as a route to reach M40 via M4.
(and the opposite directions of travel too, of course).

As satellite navigation inexorably becomes more prevalent, any travel time advantages that can be squeezed out, at relatively low cost, will become available even to unfamiliar drivers, and to those who don't read maps or only notice blue lines. Therefore, relatively minor improvements along these routes could provide cost-effective relief for the south-western quadrant of the M25.

The first alternative route (turn westwards onto M3 at J12) is, I know, already used. Travelling clockwise on M25, this route is shorter than following the orbital to M4, and Google sometimes recommends it even now. The impediments on this route are (a) M3J3, (b) A332 roundabout, (c) Bracknell's congested urban area. My ideas are:
(a) Improvement (perhaps a NE corner-cut) of M3J3
(b) Trumpet GSJ to replace the A322/A332 roundabout
(c) Bypass SW around (or a tunnel under) Bracknell.

The second route (turn westwards onto M4 at J15) is 3 miles longer than continuing clockwise along the M25 to J16, but it can occasionally be quicker. Its impediments are (a) the slightly weird M4J9, (b) the very weird M40J4 (Handy Cross Roundabout), and (c) the at-grade Bisham Roundabout. My ideas are: re-designs of M4J9 and M40J4, and GSJ Bisham

On both routes, some widening of the D2 mainlines appears feasible.

Any opinions, or better ideas?

ps. I Notice, in Jackal's recent '40 Billion Pounds' list that two of these items are present:
32. A404 Bisham Junction
35. A404/M40 Junction 4 High Wycombe
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ravenbluemoon
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Re: SW M25 Relief

Post by ravenbluemoon »

Peter Freeman wrote: Sat Aug 21, 2021 12:27 The second route (turn westwards onto M4 at J15) is 3 miles longer than continuing clockwise along the M25 to J16, but it can occasionally be quicker. Its impediments are (a) the slightly weird M4J9, (b) the very weird M40J4 (Handy Cross Roundabout), and (c) the at-grade Bisham Roundabout. My ideas are: re-designs of M4J9 and M40J4, and GSJ Bisham
I used to use this route fairly often, and the typical problem was the queues at Bisham roundabout. The terminal junctions never seemed to be quite as bad, and nothing that couldn't be solved with left turn lanes and a bit of redesign.

The main issue with that quadrant of the M25 is that the motorway is literally the only sensible route to use in the area, even for local traffic going between towns. Improving some of the local A roads so that local traffic need not use the M25 would likely help.
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Re: SW M25 Relief

Post by WHBM »

It's Daily Mail stuff that the M25 is a permanent car park. Not only is it not, but it's a magnet for all sorts of somewhat indirect journeys. For example, can you believe that the shortest journey time between Dover and Selsey, both on the south coast, is by the M25 ? Someone who regularly did Cambridge to Bristol told me the same.

Following satnav lines is a fine story for those who don't know the situation, but the majority of traffic on any route is pretty regular and well aware of the various options. Just like your own regular routes.
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jackal
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Re: SW M25 Relief

Post by jackal »

The last low hanging fruit on the A322 was snaffled up with the recent widening between Twin Bridges and Horse and Broom roundabouts in Bracknell. There is at least two lanes in each direction between the M3 and M4 now.

That said, the A322 and even A329(M) are not trunk roads, and it's not actually in the local authority's interest to attract long distance traffic to them. I don't imagine there will be any significant improvement unless it is trunked.

The A404 by contrast is trunk, and as you say has £200m committed to improving the Bisham and the M40 junctions. It should be a high quality route after this with only the M4 junction as a real constraint.

Another possible piece of the jigsaw that HE have looked at is the A331, though it is not currently trunk.

Personally I am very sceptical of how much difference these corner cuts could ever really make to M25. Suppose there was a full motorway corner cut from M3 J3 to M4 J10. The problem is that a very small proportion of clockwise traffic approaching M25 J12 is actually heading to M4 J10 or west of there. The vast majority is heading into London, going to Heathrow, accessing other local junctions along the M25, or making for strategic routes like the M40 or M1, none of which the corner cut is any use for. I'd be shocked if you even took 10% of traffic off the M25.

If you want to help out the M25 you'd get vastly more value from improvements to the M25 itself, whether widening, C/D lanes, or a parallel bypass with minimal junctions. And frankly it would be no more controversial than a motorway or HQDC bypass of Bracknell.
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Re: SW M25 Relief

Post by crb11 »

WHBM wrote: Sat Aug 21, 2021 14:22 It's Daily Mail stuff that the M25 is a permanent car park. Not only is it not, but it's a magnet for all sorts of somewhat indirect journeys. For example, can you believe that the shortest journey time between Dover and Selsey, both on the south coast, is by the M25 ? Someone who regularly did Cambridge to Bristol told me the same.
I find it surprising you find the latter surprising - there's no decent HQ east-west route, so the only viable options are via the M25, or the even more indirect A14/M6/M42/M5 option, and there's not a massive amount to choose between them. (Going via Oxford and Milton Keynes is 15 miles less than via the M25, but about half an hour longer in typical traffic according to Google.)
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Re: SW M25 Relief

Post by Truvelo »

crb11 wrote: Sat Aug 21, 2021 18:31
WHBM wrote: Sat Aug 21, 2021 14:22 It's Daily Mail stuff that the M25 is a permanent car park. Not only is it not, but it's a magnet for all sorts of somewhat indirect journeys. For example, can you believe that the shortest journey time between Dover and Selsey, both on the south coast, is by the M25 ? Someone who regularly did Cambridge to Bristol told me the same.
I find it surprising you find the latter surprising - there's no decent HQ east-west route, so the only viable options are via the M25, or the even more indirect A14/M6/M42/M5 option, and there's not a massive amount to choose between them. (Going via Oxford and Milton Keynes is 15 miles less than via the M25, but about half an hour longer in typical traffic according to Google.)
The now abandoned Oxford-Cambridge Expressway would have solved this. The A43 and A421 between M40 J9 and St Neots is a decent route but it's spoilt by being so indirect and having to use a long section of M1.
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Re: SW M25 Relief

Post by Norfolktolancashire »

crb11 wrote: Sat Aug 21, 2021 18:31
WHBM wrote: Sat Aug 21, 2021 14:22 It's Daily Mail stuff that the M25 is a permanent car park. Not only is it not, but it's a magnet for all sorts of somewhat indirect journeys. For example, can you believe that the shortest journey time between Dover and Selsey, both on the south coast, is by the M25 ? Someone who regularly did Cambridge to Bristol told me the same.
I find it surprising you find the latter surprising - there's no decent HQ east-west route, so the only viable options are via the M25, or the even more indirect A14/M6/M42/M5 option, and there's not a massive amount to choose between them. (Going via Oxford and Milton Keynes is 15 miles less than via the M25, but about half an hour longer in typical traffic according to Google.)
I have just done a Google travel time and route for Newhaven, east of Brighton, and it still shows the preferred route as up the A23 and along the M25! 114 miles compared to the coast route of the A27 etc, of 80 miles.
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A303Chris
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Re: SW M25 Relief

Post by A303Chris »

M31 anyone?
The M25 - The road to nowhere
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Re: SW M25 Relief

Post by John McAdam »

Norfolktolancashire wrote: Sun Aug 22, 2021 22:00 [...]
I have just done a Google travel time and route for Newhaven, east of Brighton, and it still shows the preferred route as up the A23 and along the M25! 114 miles compared to the coast route of the A27 etc, of 80 miles.
If you've experience of the roads along the south coast in East Sussex and Kent, then this isn't such a surprise.
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Re: SW M25 Relief

Post by Bryn666 »

A303Chris wrote: Mon Aug 23, 2021 13:31M31 anyone?
Whilst the M31 is a nice to have the real problem is some kind of small civilian airfield adjacent to the M4/M25 junction :wink:

The plans for Runway 3 never really addressed the M25 issue. Burying it in a tunnel was fine but the then HE fix for the rest of it was just more VSL and more tinkering. I'm not allowed to discuss the plans we developed for Arora Group but we were actively fighting HE's insistence that simple roundabouts and dual carriageway link roads would be the way to connect this new airport hub to the M25 - the HAL plans all relied on this because it was easier than trying to get HE to approve any free-flow designs that weren't 120km/h thanks to their rigid DMRB wonkery. This wonkery is also why all the early plans showed the 4 level stack being demolished and replaced with utter nonsense like a loop slip road into London because you simply cannot design the M4/M25 junction to meet their current 'standards'.
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Re: SW M25 Relief

Post by Peter Freeman »

The M25 J10-16 clockwise congestion is so chronic that, it appears to me, even a small (<10%) traffic reduction would be worthwhile.

My original thoughts on the M3-M4 link centred around a Bracknell bypass. That's a major project - everything else in my OP is just discrete incremental improvements. My first Bracknell thought was an HQDC half-ring around the SW of town. But then, while playing the directions game on google maps, I noticed that, at the very worst times of day, an alternative avoiding the town is already occasionally suggested. So we don't have to move this topic to the Fantasy forum: all that is required is to improve that existing de-facto bypass.

The route begins at the junction A322/B3430. It runs westwards along B3430 Nine-Mile Ride as far as Old Wokingham Road. It then runs northwards along Old Wokingham Road and Peacock Lane to re-join A329. A short length of new construction would tie it smoothly into the A329(M) GSJ.

The conventional way through Bracknell measures 4 miles and takes between 7 and 13 minutes. The bypass route (unimproved) measures 5 miles and takes 8 minutes. Dualled, shortened and properly connected, it would take only 4 minutes.

Of course, I don't know the context of my route. It looks (on google earth) ideal: almost undeveloped, enough space, hardly any obstructions. The dualling need not be quite HQDC standard, so not expensive. I suppose it would meet the usual NIMBY resistance - is there anything there that I don't know about? I have noticed the nearby golf course ... !
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Re: SW M25 Relief

Post by A303Chris »

Peter Freeman wrote: Tue Aug 24, 2021 05:09 The M25 J10-16 clockwise congestion is so chronic that, it appears to me, even a small (<10%) traffic reduction would be worthwhile.

My original thoughts on the M3-M4 link centred around a Bracknell bypass. That's a major project - everything else in my OP is just discrete incremental improvements. My first Bracknell thought was an HQDC half-ring around the SW of town. But then, while playing the directions game on google maps, I noticed that, at the very worst times of day, an alternative avoiding the town is already occasionally suggested. So we don't have to move this topic to the Fantasy forum: all that is required is to improve that existing de-facto bypass.

The route begins at the junction A322/B3430. It runs westwards along B3430 Nine-Mile Ride as far as Old Wokingham Road. It then runs northwards along Old Wokingham Road and Peacock Lane to re-join A329. A short length of new construction would tie it smoothly into the A329(M) GSJ.

The conventional way through Bracknell measures 4 miles and takes between 7 and 13 minutes. The bypass route (unimproved) measures 5 miles and takes 8 minutes. Dualled, shortened and properly connected, it would take only 4 minutes.

Of course, I don't know the context of my route. It looks (on google earth) ideal: almost undeveloped, enough space, hardly any obstructions. The dualling need not be quite HQDC standard, so not expensive. I suppose it would meet the usual NIMBY resistance - is there anything there that I don't know about? I have noticed the nearby golf course ... !
However in the 80's there were plans to build the A329(M) around the west of Bracknell, follow what is now the Sandhurst / Crowthorne bypass, then down the start of the Blackwater relief road from the meadows to Junction 4 of the M3 connecting with the proposed M3/A31 link. The M3/A31 link was built in the early 90's and is now the A331, the middle bit was watered down to the A3095. If built it would have made a huge difference. In fact in peak times its how I get on the M3 from Woodley, A329(M), through the southern industrial area then along the A3095. Quicker than the A322 Bagshot Road
The M25 - The road to nowhere
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Re: SW M25 Relief

Post by Peter Freeman »

^ Ah, I see. I'm ashamed that I haven't read up on M31 before now, on PM and CBRD.

That formerly proposed route southwards from A329(M), east of Old Wokingham Road, is what I considered suggesting, before deciding that only an el-cheapo version, predominantly on existing roads, now stands a chance. To be realistic (and not to alarm the locals!), I think it would have to be phased, gradually accumulating discrete improvements all the way along Nine Mile Ride, Old Wokingham Road and Peacock Lane. There are a couple of tight spots, so minor offline deviations might be required (add them later). It would end up well short of expressway standard, but still do the trick. Passive future-proofing should be designed in.
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Re: SW M25 Relief

Post by jackal »

I'm not sure that a 'cheapo' version would really attract a measurable amount of traffic from the M25. The cheapo version could be done simply to relieve Bracknell of local traffic, or do it properly.

A semi-directional T just south of M3 J3 and a new grade separated alignment from there to the A329(M) would relieve the M25 more than the old M31 route as it could also pick up traffic from the M3, A331, A31 and possibly A3. You'd start to have an outer orbital rather than a mere corner cut.
Last edited by jackal on Tue Aug 24, 2021 15:25, edited 1 time in total.
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Re: SW M25 Relief

Post by Peter Freeman »

^ Yes, but that's half of the M31, and it's just not going to happen, is it?
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Re: SW M25 Relief

Post by jackal »

^ Edited to make clearer that it's not the same as the M31 - though it's no more likely!
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Re: SW M25 Relief

Post by Peter Freeman »

^ I understood the idea, and my "half ..." was not literal.

If a London outer orbital were to be created by co-opting many existing roads and improving them, and building short tactical new bits to link them properly, I'd be as delighted as you. But if a 'POLO' hasn't happened yet, after all these years, it's not going to happen.
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Re: SW M25 Relief

Post by Bryn666 »

Peter Freeman wrote: Tue Aug 24, 2021 15:37 ^ I understood the idea, and my "half ..." was not literal.

If a London outer orbital were to be created by co-opting many existing roads and improving them, and building short tactical new bits to link them properly, I'd be as delighted as you. But if a 'POLO' hasn't happened yet, after all these years, it's not going to happen.
Unless it allows the area outside of the London green belt to be concreted over for houses, National England Agency for Highways will have no interest in facilitating it. Most of RIS2/3 is purely to allow development with the optional benefit of it might reduce congestion and collisions on the road network.
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Re: SW M25 Relief

Post by Micro The Maniac »

A303Chris wrote: Tue Aug 24, 2021 09:08 However in the 80's there were plans to build the A329(M) around the west of Bracknell, follow what is now the Sandhurst / Crowthorne bypass, then down the start of the Blackwater relief road from the meadows to Junction 4 of the M3 connecting with the proposed M3/A31 link. The M3/A31 link was built in the early 90's and is now the A331, the middle bit was watered down to the A3095.
While simultaneously building the College Town and Owlsmoor estates, thus making sure there is no possibility of upgrading the A3095 to a dual carriageway :roll: That, and the increased environmental classifications of large areas, to Special Protection Areas - making them bulletproof. This all not helped by the poorly aligned new-ish roundabout for the Broadmoor development.
If built it would have made a huge difference. In fact in peak times its how I get on the M3 from Woodley, A329(M), through the southern industrial area then along the A3095. Quicker than the A322 Bagshot Road
it is surprising, or perhaps not, the amount of traffic that cuts through the Southern Industrial Estate (both ways)!
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Re: SW M25 Relief

Post by skiddaw05 »

Not exactly cutting the corner when you look at it but I used the M3 and A322 to get from the M25 to the A3. The A322 was a much nicer drive than it's appearance on a map would suggest
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