M4 Junction 3 to 12 Smart Motorway

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A303Chris
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Re: M4 Junction 3 to 12 Smart Motorway

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ChrisH wrote: Tue Feb 02, 2021 11:14 The newsletter for January 2021 shows that they are planning weekend closures on the Slough/Maidenhead section every weekend this Spring. Now that the bridges are replaced, they still need to do the majority of the works to the central reservation and hard shoulder in one year, which took over two years on the western section.

Given the very low traffic levels this seems like a good option to me. The disruption seems to be relatively localised when I've seen it.
I think they are making the most of the low traffic levels as before Covid came on the scene there were weekend closures but a lot less regular then they are now. As you say it makes sense as you can get a lot done over a full weekend closure.

How, hopefully as things get better during the Spring, they should reduce as before Covid, when they did close the M4, the M40 and M3 were rammed.
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ChrisH
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Re: M4 Junction 3 to 12 Smart Motorway

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Also worth noting I haven't seen streetlighting being reinstalled between J10 and J12, which was there before the works. Whereas the lighting has been reinstalled on the concrete central barrier east of the M25. Is this another bit of value engineering?
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Re: M4 Junction 3 to 12 Smart Motorway

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Well the full opening of J8/9 to J12 didn't go exactly to plan even though it is all completed.

The signs at J8/9 westbound and J12 eastbound have been dropping from 3 months to opening, 2 months, down to one month at the end of February. This weekend that changed to six months again, but the speed limit has been increased to 60mph in both directions.

Every thing has been removed apart from cones along lane one, even the VMS say 60 mph.

I did think the emergency laybys were two miles part as originally designed and not one mile as now recommended, so all I can think is they finished the works and at the RSA, someone said, you don't have enough emergency refuges. Pretty bad if this is the reason.
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ChrisH
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Re: M4 Junction 3 to 12 Smart Motorway

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A303Chris wrote: Tue Apr 06, 2021 14:10 Well the full opening of J8/9 to J12 didn't go exactly to plan even though it is all completed.

The signs at J8/9 westbound and J12 eastbound have been dropping from 3 months to opening, 2 months, down to one month at the end of February. This weekend that changed to six months again, but the speed limit has been increased to 60mph in both directions.

Every thing has been removed apart from cones along lane one, even the VMS say 60 mph.

I did think the emergency laybys were two miles part as originally designed and not one mile as now recommended, so all I can think is they finished the works and at the RSA, someone said, you don't have enough emergency refuges. Pretty bad if this is the reason.
I have been waiting for newsletters but nothing on the HE webpage since January. I also drove the J10-12 section this weekend and it just needs cones removing now as far as I can see.
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Re: M4 Junction 3 to 12 Smart Motorway

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ChrisH wrote: Tue Apr 06, 2021 14:52 I have been waiting for newsletters but nothing on the HE webpage since January. I also drove the J10-12 section this weekend and it just needs cones removing now as far as I can see.
It along with J8/9 to J10 has been like that since February. While I can see the point of J10 to J8/9 remaining, given the road works start a mile before J8/9, given there are lane drops at J11 and J10 and a lot of southbound M25 traffic goes A329(M), A322, M3 anyway, I can not see why they have not opened J10 to J12
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Re: M4 Junction 3 to 12 Smart Motorway

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I’m sure they’ll post an update soon - but maybe it’s worth sending an email?
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Re: M4 Junction 3 to 12 Smart Motorway

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Latest up date:

Junction 8/9 to Junction 12 is all finished and was due to open Easter. It is now at 60mph with lane one coned off, reason they are retro fitting the automated vehicle detection systems the Government say have to be installed before opening, so it has been put back 6 months.

The sign frames for junctions to the East are now up and it seems only Junction 7 will be ALR running through with lane drops at J6 and J5. The original scheme showed ALR apart from J10 and J4b which made sense but J11 and J8/9 are definitely lane drops and the rest look that way as well.

Between J8/9 and J4b , to me this makes the whole thing pointless as given the frequency of the junctions lane one is just going to become a glorified slip road which is what happens on the M3 J2 to J4b.
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Re: M4 Junction 3 to 12 Smart Motorway

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A303Chris wrote: Wed Apr 28, 2021 13:47 Latest up date:

Junction 8/9 to Junction 12 is all finished and was due to open Easter. It is now at 60mph with lane one coned off, reason they are retro fitting the automated vehicle detection systems the Government say have to be installed before opening, so it has been put back 6 months.
I don't see why they can't just mark a solid line between lane 1 and 2 and use it as a hard shoulder for now. At least we will be able to go back to 70. The line can be removed and repainted afterwards.
A303Chris wrote: Wed Apr 28, 2021 13:47 The sign frames for junctions to the East are now up and it seems only Junction 7 will be ALR running through with lane drops at J6 and J5. The original scheme showed ALR apart from J10 and J4b which made sense but J11 and J8/9 are definitely lane drops and the rest look that way as well.

Between J8/9 and J4b , to me this makes the whole thing pointless as given the frequency of the junctions lane one is just going to become a glorified slip road which is what happens on the M3 J2 to J4b.
This is stupid. I don't see why we have a problem with through junction running in modern SM projects.
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Re: M4 Junction 3 to 12 Smart Motorway

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I suppose it depends on the levels of traffic expected to exit at each junction - I was using the M4 regularly about three years ago for a job out west, and it struck me that there seemed to be a significant level of regular queueing back onto the main line at evening rush hours at many of the junctions. Perhaps the figures show that increasing capacity on the main line without associated junction stacking space being increased is likely to make the problem worse and perhaps that's the reason for it? All this of course being speculation!
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Re: M4 Junction 3 to 12 Smart Motorway

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A303Chris wrote: Wed Apr 28, 2021 13:47
Junction 8/9 to Junction 12 is all finished and was due to open Easter. It is now at 60mph with lane one coned off,
Maybe it's possible I wasn't paying as much attention as I thought I was (or should have been), but the change from 60 to 50 wasn't completely obvious. On cruise control at 60, passing a sign every few hundres metres that says 60, maybe I stopped paying attention to the signs. But at some point as I was going through 8/9 I clocked that the signs I was now passing said 50.

I seem to have got away with it, thankfully.
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Re: M4 Junction 3 to 12 Smart Motorway

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EpicChef wrote: Wed Apr 28, 2021 14:27 This is stupid. I don't see why we have a problem with through junction running in modern SM projects.
At traditional motorway junctions, with a roundabout and two bridges, it saves rebuilding the bridges. At J5 for example the bridges over the roundabout had no hard shoulder to cannibalise

https://www.google.com/maps/@51.4918709 ... 384!8i8192

therefore it saves the expense of two bridge rebuilds.
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Re: M4 Junction 3 to 12 Smart Motorway

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WHBM wrote: Wed Apr 28, 2021 21:21
EpicChef wrote: Wed Apr 28, 2021 14:27 This is stupid. I don't see why we have a problem with through junction running in modern SM projects.
At traditional motorway junctions, with a roundabout and two bridges, it saves rebuilding the bridges. At J5 for example the bridges over the roundabout had no hard shoulder to cannibalise

https://www.google.com/maps/@51.4918709 ... 384!8i8192

therefore it saves the expense of two bridge rebuilds.
But for the fact the the bridges have been widened anyway, so no expense has been saved.
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Re: M4 Junction 3 to 12 Smart Motorway

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Went through the bit from the M25 to 8/9 this afternoon and noticed that some of the overbridges between 6 and 7 have an extra span over ''nothing' to the north of the motorway. Since an embankmnent would be far cheaper than a double span, I would reckon that a development access road of some kind is probably planned to run parallel to the motorway at some stage.
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Re: M4 Junction 3 to 12 Smart Motorway

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M4 Cardiff wrote: Wed Apr 28, 2021 21:39 Went through the bit from the M25 to 8/9 this afternoon and noticed that some of the overbridges between 6 and 7 have an extra span over ''nothing' to the north of the motorway.
It's for HS4.
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Re: M4 Junction 3 to 12 Smart Motorway

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hoagy_ytfc wrote: Wed Apr 28, 2021 21:09
A303Chris wrote: Wed Apr 28, 2021 13:47
Junction 8/9 to Junction 12 is all finished and was due to open Easter. It is now at 60mph with lane one coned off,
Maybe it's possible I wasn't paying as much attention as I thought I was (or should have been), but the change from 60 to 50 wasn't completely obvious. On cruise control at 60, passing a sign every few hundres metres that says 60, maybe I stopped paying attention to the signs. But at some point as I was going through 8/9 I clocked that the signs I was now passing said 50.

I seem to have got away with it, thankfully.
The signs are poor, they change about a mile before J8/9 but its just a basic 50, which look very similar to the 60, although once past 8/9 its obvious as you are back on narrow lanes.
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Re: M4 Junction 3 to 12 Smart Motorway

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It seems the vehicle detection equipment has now been installed between J8/9 and J12, with the latest newsletter saying four lanes will be open fully with a 60mph limit from October while they test the technology and 4 lanes with a 70 mph limit by the end of the year.

However, what is annoying is the constant weekend closures of the road between J8/9 and J3, some section is closed every weekend or overnight. Last Tuesday was a classic, M4 was closed J7 to J5 overnight, while the M40 was closed between J3 and J4 and the A404 between the A308 and A4130, talk about coordination not.

However why in the south east as was the case on the M3 and M23 works, do they need so many weekend closures, they do not seem to be needed on the M6 and M1 works. It is a pain and as I have family near Datchet basically the closures just screw the village every weekend.
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Re: M4 Junction 3 to 12 Smart Motorway

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A303Chris wrote: Mon Sep 20, 2021 10:45However why in the south east as was the case on the M3 and M23 works, do they need so many weekend closures, they do not seem to be needed on the M6 and M1 works. It is a pain and as I have family near Datchet basically the closures just screw the village every weekend.
I don't know the answer to the question but I agree it's incredibly irritating. To have closed one of the major radial motorways from London, this often, and for this long on each occasion, seems absolutely incredible. I can't think of a precedent for it and I don't know how it can be justified.

I can understand needing to close a road at certain points in a major project to carry out certain jobs, like bridge demolition, but I can't understand why there have needed to be this many closures over a period now running in to years. It feels a bit like a project plan made for the convenience of the project and not for the convenience of the travelling public.
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Re: M4 Junction 3 to 12 Smart Motorway

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Chris5156 wrote: Mon Sep 20, 2021 11:34
A303Chris wrote: Mon Sep 20, 2021 10:45However why in the south east as was the case on the M3 and M23 works, do they need so many weekend closures, they do not seem to be needed on the M6 and M1 works. It is a pain and as I have family near Datchet basically the closures just screw the village every weekend.
I don't know the answer to the question but I agree it's incredibly irritating. To have closed one of the major radial motorways from London, this often, and for this long on each occasion, seems absolutely incredible. I can't think of a precedent for it and I don't know how it can be justified.

I can understand needing to close a road at certain points in a major project to carry out certain jobs, like bridge demolition, but I can't understand why there have needed to be this many closures over a period now running in to years. It feels a bit like a project plan made for the convenience of the project and not for the convenience of the travelling public.
This is exactly right. When I queried these with HE a year or so ago they came back with responses around doing large areas of resurfacing, which weren't possible with overnight closures. Even if that were true it doesn't explain using full closures for what must be routine work, now that all the bridge replacements have been done. (And of course, each bridge replacement caused two full weekend closures - no coordination.) If they had been able to fully close the M4 for a month at the height of the Covid lockdown and do the whole lot, it would have been a good use of time. These closures are certainly not customer-friendly.
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Re: M4 Junction 3 to 12 Smart Motorway

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ChrisH wrote: Mon Sep 20, 2021 13:20When I queried these with HE a year or so ago they came back with responses around doing large areas of resurfacing, which weren't possible with overnight closures.
What absolute bobbins. I wonder if money plays a part - are they doing the job more cheaply than if they had kept the road open through routine jobs like that?
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Re: M4 Junction 3 to 12 Smart Motorway

Post by thatapanydude »

Maybe the fact that you have the A40 parallel and to a lesser extent the A30 is part of the thinking in getting away with closing the M4.

Most journeys from Maidenhead to London are interchangeable between the M4/A40.
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