Safe Speed Forums

a new vision greeted my entry onto the M42 this morning, not the usual flashing advisory limit.... but a bright red ringed mandatory VSL of 50.

i know people have opinions on this, and the M25 is either go or stop with nothing inbetween when i've used the VSL sections on there... but i'm giving the benefit of the doubt for now and am willing to hold judgement.

my experience of the M42 is that there is a greater period where the traffic volume is marginal where lower speeds would help flow, as opposed to M25 where often no amount of speed reduction is going to prevent gridlock due to shee volume.

this morning was not a great test as traffic wasn't so bad when i was on. progress was good though with most lanes cruising at 50. not sure that the section of 60 made much difference over a 70 NSL but didnt seem to cause a problem.

two things it didn't address were
- distance between cars, still too small in relation to even a reduced speed
- lorries overtaking lorries, maybe the 50 encouraged this as they're not all sat on the limiters. the only wave of braking i came across was as the traffic came to one of these moving chicanes.

like i say i'm willing to see how this goes...

PS no hard shoulder running yet, not due till 2007 i think, which is a different kettle of fish.

Can you clarify what you mean when you say distance between cars and lorries overtaking was not addressed - in relation to the 50 VSL?

hi W.
i'm not sure off the top of my head what the reasons for implementing VSL in this location are.. but i'm fairly sure they'll be trying to justify it with a safety & improved traffic flow double whammy.
the two things i mention (below) are safety & flow issues this system doesn't and can't address, it hadn't occured to me that in fact the latter issue it may in fact encourage.

- in the first case.... it doesnt do anything for road safety.. people are still tailgating... just at 50 rather than 70.
- in the second case.... it doesn't help traffic flow (or safety a great deal) if it encourages lorries to overtake each other at 2mph differential speed.



based on 2 further m42 journeys today, outbound was about midday, some traffic with a 60limit, not really needed i.m.o.
on the way back a bit heavier traffic, some confused drivers braking for the signs etc, being over cautious and causing the trucks to go round them.

i'm hoping driver responses will settle down and become more rational as it becomes more widely understood.

The reason for the installation was to "improve the traffic flow" where the M40 North and M42 North merge into the M42 North. There is so much traffic that most weekdays the tailbacks go back to J3 or earlier for the M42 - on really bad days it starts at J1.

The target solution is a cheap and nasty use of the hard shoulder to make 4 lanes, but they are getting to it in stages, and it is very much an "experiment". They have been building in "refuges" (like a lay-by) back from the hard shoulder, but before they allow use of the hard shoulder they need the traffic to go slower, so they have also installed the camera enforced variable speed limits. Once the variable limits are considered to be working, they will introduce the drive on the hard shoulder to allow 2 lanes to join 2 lanes giving 4 lanes.

Lots about it here: Highways Agency buggering about with M42, blah, blah, blah

What they don't seem to mention, is that the real answer is to build a proper new lane, or even more obviously if you are joining a heavily used motorway with a new motorway that you expect to be heavily used, then build in enough lanes in the first place...

yup... well aware of the theory re.
any comment on the practice ?

No,

Because I avoid the road whenever possible - there is a nice little country back road route from M42 J3 to Shirley despite their best efforts to muck it up with "Junction Tables" (I really hate those, and take narrower and more dangerous roads to avoid them), reduced speed limits (ignored by everybody - just join the traffic doing 65 in a 40 that used to be a 60) and road closures caused by the building of the new "village".

I might try it sometime, but I got so used to my little back road, that I automatically come off at J3 all the time now even when it might be slightly quicker via the motorway.

I take it the A46 will now go mental as cars seek to avoid M42

The M42 Active Traffic Management project is a PILOT.
It was specifically developed to look at ~intelligent~ ways of managing the network. The project is less expensive than building another lane, but it is not cheap and nasty.

Congestion will rise far more heavily than we can build roads. Building more roads / lanes is not the answer.
If you 'built enough roads in the first place' there would be no room for anything else, so rather short-sighted perhaps.

The use of the hard shoulder is NOT to make 4 lanes, it is to provide another lane at cerain peak times when it is needed. You will not be able to exceed 50mph in the hard shoulder lane.

The Emergency Refuge Areas (ERAs) have been built specially and include much better technology including improved phones. These ERAs will be constanly monitored by CCTV.

This project has taken years to develop and implement because so much research, consultation and processes had to be done a safety was paramount in all of this. It is implemented in stages partly because of safety, but also because they are major milestones.

It will be interesting to see how successful this project is, but in terms of ITS, it has broken new ground in the U.K. It has proved successful in other countries, and best practice was reviewed and adapted for the U.K.

winston... i get the feeling you're close to this project ..enlighten me!

have to admit at night it does look rather like they've turned the christmas lights on, the gantries are certainly brighter & seem more frequent than the M25.

and exciting new development this morning, they'd turned the Xs on over the hard shoulder

I drove through the full length of the M42 (southbound) during morning rush hour on Wednesday morning. if it has improved the traffic flow to any extent, I'll be amazed. There was a huge queue from before the M6/m42 interchange that didn't really dissipate until well after the variable limit zone. Drivers DO brake when limits change downwards and tailgating, changing lanes without indicating, and all other bad driving wre still as evident as ever.

I hate that section of the M42, I feel the driving gets worse, the cars get close togther. I only go that why if I can not avoid it . I don't feel safe when I drive though there.

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i only use it in the morning circa 7:30 from NEC to Shirley.... quicker of two evils really, usually faster than the x-country route even if its crawling at 40.

i don't do it in reverse as i dont like the free for all lane markings on the NEC roundabout & the taibacks caused by barrier work on the a45 near cov.

Well I don't think it is working. I had to go into work twice this week, and the motorway tailbacks were to J2 yesterday and J1 today meaning that my 27 mile journey into work took 1 hour 15 min and 1 hour 25 min. averaging 20 mph for a journey that is 3/4 motorway, d/c or open A roads.

A work colleague that lives close to me, but has the advantage of being able to park on-site, doesn't cut from J3, but drives around to J5, and has just been chatting with me about how bad it is. He says that the variable limits with cameras are making the situation much worse, with increased lane changing, tailgating, concertinaing etc, and that the average speed has gone down dramatically. As a consequence when he gets off the motorway he feels very stressed and finds himself driving faster elsewhere just to make up time.

Perhaps it will get better when they start using the hard shoulder to give 4 lanes (which is exactly what it is), but at the moment a lot of money has been spent for zero gain, unless you count the excuse to mount speed cameras over a motorway.

has anyone actually seen any cameras?

Yes, there are some on the gantries, but not on *every* one and not on *every* lane at any gantry. This is unlike the M25 where if one lane has cameras, they all do. I'd reckon on them being easily moved from place to place, mind.

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Keep right on to the end of the road ...

Yes you can see them on the back of the gantries behind the signs. The cameras are oblong box shaped and painted grey, and as CJB says not fitted on every one. I would also agree they could be moved, this because there are speed measurement marking under every gantry on all three lanes.

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Useless laws weaken necessary laws.

not gatsos then?
what are they?

Has anyone looked at the new overhead signs through a wing mirror?

Doesn't it look really weird? Very distracting.

ah yes.... found the cameras

or that is, someone on the opposite carraigeway illuminated me.

I had the unnerving experience of driving through the full length of the Management Controlled section of the M42 yesterday, and of what I experienced IMO is what I expected this section is all about. I hit this section every Thursday at around 2.00pm every week, and before this system was up and running I have never had any problems and most of the time sail right through (except when there has been an accident/or incident).

Travelling on the M40 north and just before the M40/M42 junction the message boards where displaying M42 Management System Operational. As soon as I left the M40 onto the M42 (north bound) I was greeted with the message CONGESTION ON M42, and 60mph Obligatory speed limit. There was no congestion in sight, however I gave it the benefit of the doubt as I still had a long way to go. Soon after entering the overheads changed to 50mph obligatory (still no sign of congestion). It stayed 50mph obligatory until about half a mile from the M6 then raised to 60 and eventually NSL when you hit the M6 (end of Management System). I did not see one ounce of congestion, or did I have to slow down once for the whole length of this Management system.

If there was congestion (and there wasn’t) why could they not have used the advisory speed limit signs like they do on the rest of the motorways (not that they mean much either).

Already they are abusing the system, it’s being used to intimidate drivers, and it’s not what we are all being told it is supposed to be for (managing traffic and safety). It is going to be used as another addition to the governments’ revenue gathering system. The M42/M5 will be my next route (not much difference in mileage).

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Useless laws weaken necessary laws.