Safe Speed Forums

The Highway Code is pretty clear cut - merging traffic on dual carriageway/motorway on ramps must give way to traffic already on the main carriageway.

However, the courtesy given by some drivers in pulling into the middle lane to allow on-ramp traffic free access to the left-hand lane is causing many (most!) drivers to expect to be allowed on in this way, leading to near misses when on-ramp traffic refuses to slow down or, if necessary, stop at the Give Way lines or when left-lane traffic forcibly switches lanes.

I've lost count now of the number of times I have had to brake to avoid collision with a determined (illegal) on-ramper, or had lights flashed/gestures waved at me because I have refused or, more likely, been unable to 'give way' to on-ramp traffic or a 'left laner' wanting to move over to let the on-ramp traffic on.

With common sense and a bit of forward planning, surely we can anticipate the possibility of traffic joining at a slip road?

If I'm in the left lane I try and create myself a gap when approaching a junction, so that I can either adjust my speed early or move lanes if other traffic wants to join.

I think that insisting on your right of way to the extent of forcing joining traffic to have to slow at a point when they should be accelerating creates danger out of nothing, and actually shows a lack of courtesy and anticipation on your part.

Strange things though, "on ramps". Where else do drivers indicate right in order to turn left?

This is one example of where a little co-operation goes a long way so I agree with JT on that point.

Nonetheless there are those who will try and force the issue by barging their way onto the main carriageway, these are often the types who ignore the gaps that have been left for them and charge right to the end of the sliproad and try and join there, some folks just have to get in FRONT of you

Or, on occaisions when you pull out to let them on, you find yourself almost past them when they accelerate to undertake you. Forget the curtosey you just showed, oh no...lets just undertake and get out into that FAST lane

We could do worse than take up the German 'zipper' law, whereby each car on the main cariageway must let one car on the sliproad join at the end if possible.

I would agree, but my point is that too much of this has led to an expectation amongst drivers that they will always get a free and easy passage on to the main carriageway whether or not it is safe or feasible for main carriageway traffic to give them it. Very often I see left lane traffic switching lanes instinctively (and more often than not unobservently) when approaching an on-ramp 'just in case' there is traffic merging. Moreover, I believe this is contributing to the 'middle lane hogging' problem as nervous drivers would rather sit there than cope with the indignant on-ramper bearing down on them from the left.



If the traffic on the on-ramp has to slow or stop, then so be it - the Give Way lines are indication enough that they should anticipate this eventuality. I wouldn't force someone on an on-ramp to slow down unnecessarily, but likewise if I was faced with the choice between that and making someone to the right-and-behind (or even adjacent) slow down or swerve then I know what the Highway Code intends, and so should the slip-road driver. The problem with 'courtesy' as you put it is that it is creating an unwritten rule that is dangerously at odds with the Highway Code and certain drivers have come to rely on.

Not directly related to your point, but has anyone tried getting onto the M6 at Lancaster? The 'onramp' runs parallell to the motorway for about 50 yards at the most! It's an absolutely horrible junction, and means that you really need to have your wits about you because the decision as to whether you should 'go for it' or slow down and be prepared to come to a halt has to be made in a split-second. Fortunately, most of the traffic already on the motorway seems aware of this, and (so far!) has always moved over for me.

But I don't like it.

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-mike[F]
Caught in the rush of the crowd, lost in a wall of sound..

Yep, when travelling northbound that junction is lethal. This is simply because the junction is immediately before the Lune river crossing, where the motorway is restricted to the width of the bridge, so no easy way of lengthening the sliproad.

The irony here is that they just spent millions doing a massive improvement scheme at that junction, yet did nothing about the one dreadful feature that any observer would have spotted within seconds!

IM(H)O the money would have been better spent on widening the bridge so that the sliproad could have continued over it.

It's a fair point Mike, and it is relevant because short on-ramps are a danger as they present a problem to the driver that the Highway Code protocol doesn't really address.

The Lancaster M6 problem highlights yet again how the onus is unnecessarily put on every driver using the road to compensate for a danger that could have been better dealt with through improved road engineering.

It's a scandal that money-saving-policy decisions like these get made on the justification that drivers "should be more careful".

Actually, the Highway Code IS pretty clear cut. It contains no reference at all to "giving way" when traffic streams merge. See this:

http://www.highwaycode.gov.uk/23.shtml#233 which includes: "give priority to traffic already on the motorway"

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Heh, I thought all the roadworks round there were just resurfacing and nothing more?

I'd have thought a good way of dealing with it would be to reduce the motorway itself to 2 lanes just before the junction, then have the oncoming traffic join as the inside lane, kind of like this:-



That's the only way I see (short of widening the bridge or moving the junction) of giving joining traffic a longer sliproad.

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-mike[F]
Caught in the rush of the crowd, lost in a wall of sound..

With cases like the northbound M6 at Lancaster, it would nearly be safer to remark the dotted lines the other way, so that the slip road becomes lane 1, and the old lane 1 has to give priority to it!

I suppose a lot of junctions are in effect like that, where the traffic merges down to two lanes and a new lane joins from the left, which therefore "inherits" priority.

As things stand, traffic joining has very little opportunity to "be safe". The first sight of the motorway is when they are only a hundred yards or so from joining it (in the typical "climbing" access lane), and they have very few options open if there isn't a handy gap available. They can either accelerate to arrive earlier if a gap is available ahead, or they can slow down to slot into a later gap. The latter is fraught with hazard, as not only does it completely mismatch your speed to that of the motorway (making it ever harder to join), but also it increases the risk of being shunted by the car blasting up the sliproad behind you, busy looking over his shoulder rather than at you braking in front of him.

So in reality, the "joiner" has few options available, and as Mike says he has but a few seconds to make his commitment. Also he cannot "choose his moment" to join the motorway, he has to take what he finds at the time he arrives.

Meanwhile, traffic already on the motorway has every chance to anticipate and prepare for the arrival of joining traffic. As I said earlier, it's not as though you can't tell that a junction is coming, so all it takes is to ensure that a reasonable space is available in front, for you or a joining vehicle to accelerate into, or be ready to move over into the second lane if the need arises. Either way, you have the option to be in control and to ensure safety, the joining car doesn't.

[edited to say Sorry Mike - looks like our posts "crossed"! Oh, and the roadworks at Lancaster about 2 years ago totally remodelled all the junctions under the M6, but left the last hundred yards of the sliproad "as was"]

Hehe, nice to see that we're both thinking along the same lines though! And I didn't know about the roadworks two years ago, wasn't on the roads then so such things didn't interest me!

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-mike[F]
Caught in the rush of the crowd, lost in a wall of sound..

We have been talking about J34, have we not? This is such a well-designed junction that Chris Marshall has a "Bad Junctions" page about it on his "CBRD" site:

http://www.cbrd.co.uk/mistakes/badjunctions/6-683.shtml

All becomes clear when you read that it wasn't meant to be a full junction at all.

Moving on, what do you all think of ramp metering by traffic lights? Around Birmingham on the M6 we have quite a few junctions with this feature. They stack up traffic on the ramp and let it on in small doses instead of the constant stream, so that M'way traffic has some time where there is no merging. Conversely, when traffic is let loose it arrives as a dense mass, which strikes me as possible more dangerous. Any stories to tell about this?

Ah.. It all begins to make sense. But surely it was somewhat short-sighted, when building the motorway, to have no junction nearer to Lancaster than 6 miles away? As it is, J34 provides good access to getting into the town (especially with the nice shortcut up Bulk Road!), it's just that the junction itself is.. crap.

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-mike[F]
Caught in the rush of the crowd, lost in a wall of sound..

Well, the past is another country, and this motorway was built in the early 60's. If you think that junction is bad, try this:

http://www.cbrd.co.uk/mistakes/badjunctions/50-4221.shtml

I think you'll agree it's horrific, but the M50 is a very quiet road.

Oh J34 M6 (shudder)!

Been on most of the ones listed on your site CJB! They are !!!

But there are more:

M60 is one long disaster - Simister! Worsley! Barton! Cheadle! Stockport!

J12/J13 M60 - Worsley! AAARGH! People join the anti-clockwise motorway from this "des res "suburb of Manchester. L1/L2 disappear into the M602/M62 about half mile up the road. So joiners have to pull out into L3/L4 immediately if they wish to go to Old Trafford, Trafford Centre and Stockport. They have to dodge M60 traffic wishing to join M602 to Eccles/Salford or M62 - Liverpool. (Clockwise, Worsley "villagers" have to avoid traffic from shortest on-ramp I have ever seen from M602, then they have to contend with M62 traffic joining as L1! Collisions and shunts are "normal" in this area!

J11 Anticlockwise. Very short steep uphill on-ramp which joins at foot of Barton Bridge. Collisions galore here!

This is being tried on the M3 in the Winchester area as well. I've not heard that it's caused any problems, but then I'm not local. But that bit of the M3 is nowhere near as busy as the M6 and I'm not convinced it was needed in the first place. Not that I'm suggesting anyone's cherry picking the locations for these things I haven't noticed if there's much of a run-up from the lights for slip road traffic to use to match speeds with the motorway traffic, but I'm assuming there must be one. It doesn't make a lot of sense having cars leaving the lights and only getting up to 40 or so before trying to merge safely with traffic moving at nearly twice that.
There's a few places I know where lane 1 becomes the slip road and disappears until the on-slip on the other side as Mike{F] describes. I think most of the M25 between the A3 and the M40 is like this, and it seems to work okay. Sure, there's always some clown who wants to get from lane 3 or 4 to the exit in about a hundred yards, but they would cause the same problems anyway. The only other problem is that very occasionally someone doesn't read the signs properly, fails to notice they're about to leave the motorway and ends up having to jump back into lane 2 at the last minute. Doesn't seem to happen often though.

The old ramp metering system on the M6 is a rather stupid design, since it unleashes a lot of cars in one go, which causes problems on the main carriageway.

The M3, and soon-to-be M42 versions of this unleash 1-2 cars at a time, thus breaking up the flow of traffic entering the motorway into more manageable chunks. Whether the slip roads are long enough for people to accelerate is something of a concern, though.

In my experience, most of the problems are caused by the increasing numbers of drivers who, for no good reason, accelerate to no more than 30-40mph on the on-ramp, and then expect vehicles on the motorway to give way to them.
Firstly, all but the most gutless of cars are capable of accelerating to motorway speeds on most motorway on-ramps - especially as most on-ramps are downhill. If you're doing a reasonable speed at the end of the on-ramp, you can usually slot into the motorway stream almost effortlessly, and you have plenty of scope for adjusting your position.
Secondly, as most on-ramps are downhill, brisk acceleration here saves fuel, as opposed to accelerating once on the relatively flat motorway. You have gravity working for you.

The American system is much better.... they have an alternating green/red light and release one car about every three seconds. Seems to work very well in practice.

Why can't people just anticipate what is going to happen.

I used to drive past the A3-Hogs Back Northbound juntion, every week we'd spot a rear end shunt in the sliproad guaranteed. (guess who'd be in the car in front) we ran a monthly tally count. Speed limits never solved the problem either, just plain stupid driving is the cause.

In Denmark it's compulsory to make way for offramp traffic, not exactly rocket science is it?. The highway code is stupidly outdated on this subject in my opinion.

How often do you get blocked by someone in the middle lane refusing to move over or not noticing you need to move over, to make safe progress for all.