Safe Speed Forums

At the end of a hill climbing lane on a motorway, do you think it is safer to merge fast moving traffic in lanes 3 and 4 with no escape route, or merge slow moving traffic in lanes 1 and 2 with the hard shoulder as an escape route ?

My personal opinion is that merging the fast moving traffic with no escape route is very dangerous. However this is the opinion of a motorcycle/car user, I am interested in what the LGV drivers think.

If the merge area is long enough then it shouldn't matter which lanes merge so long as there is adequate warning.

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Science won over religion when they started installing lightning rods on churches.

Your not reffering to the M62 at Saddleworth Moor are you? In that case there are warnings for a mile so I don't see much of a issue, and in my opinion is probably better as the vehicles using 4 can vary their speed with greater ease to merge then trucks in lanes 1 and 2.

I vaguely remember driving up the mountain to get to Andorre, this road was generally 3 lanes, with the uphill side having 2 lanes. When these lanes ended it was the 'slow' lane which had to give way to the 'fast' lane.
It seemed to work ok, only difference being that it's the HGVs who were in the 'fast' lane going flat out overtaking everything else!

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Andrew.

I'm thinking about the M5 just south of Bristol, where 3 climbing lanes have just been finished.

The warning of lane merging is (IIRC, will check later) only 400 yds. When you get to the point where the merge happens, the lane divider dissappears and about 50 yds later white hatchings emerge from the center of the motorway indicating where the single remaining lane is, and then recede back to the central reservation and the motorway is now 3 lanes + hs.

From the end of the lane divider to the end of the white hatchings is about 100 yds.

If lane discipline in Britain is anything to go by then the slow lane should have to merge, rather than the fast lane!

My dad told me about his drive on the six-lane M25, with most traffic in the fastest 3 lanes and the slow 3 lanes very quiet. Build a 10 lane road and people will drive in the 10th lane when it is quiet!

I found some diagrams which show what I mean

http://www.highways.gov.uk/roads/docume ... 19_20n.pdf


http://www.highways.gov.uk/roads/docume ... 19_20s.pdf

I know the bit you mean. They've done exactly the same thing on the M4 eastbound, near J18 I think. It seems that the amount of warning is adequate in my opinion, but there's almost always some muppet who thinks that 100 yards before the pinch point would be a good place to overtake a L3 vehicle doing 80 - 90 mph

I've noticed with the one on the M4 that when the carrriageway changes from 3 lanes to 4 at the bottom of the incline, it's L1 that splits, but at the top, it's L3 & L4 that merge. So you get a driver originally in L1 who hasn't noticed the extra lane (or is too scared to change lanes, or something) ending up sat in L2 once it's back to 3 lanes. Similarly, a L2 hogger becomes a L3 hogger
Or am I being too judgemental?

The northbound looks like it could use a bit more hatching, the southbound appears to have none at all.

The R/H lane merges I know (M62 E at Saddleworth and M621 approaching J27 on the M62 work quite well but do have plenty of hatched area if it does go wrong.

The problem with making the merge on the L1 side is that HGVs need more time to plan and execute a merge, the result being a that the last mile or so of teh crawler lane will be devoid of traffic. You can see this effect on the M62 W approaching J24 where HGVs move to L2 and L3 (of 4 lanes) a mile and a half before the junction where L1 splits off. Effectively wasting over a mile of crawler lane. This section was much better before it was redesigned and L3 and L4 merged opposite the off slip.

Agreed - also by definition most traffic in Lane 4 should be overtaking and be looking for a way back in.

The vast majority of examples where motorways lose a lane without L1 becoming a slip road lose it on the right (e.g. eastbound M62 at the M6 junction, northbound M66 near Bury).

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

Interesting, the only similar place I recall driving through something like this is on the M25 clockwise between the M4 and M1, here when 4 lanes merge to 3, it is L1 and L2 that merge.

As a car driver being in L4 that becomes L3 it always struck me as a much safer way. If it all went pear shaped in the L1 L2 merge you always hard the hard shoulder as an emergency exit.

I wonder what the accident statistics are for the two different schemes ?

M6 , has had L4 merging back into L3 fo years ( at least 15 possibly more) , has warnings about at least 600 yds back and only incident i've seen has been someone trying to change a flat on the hatched bit at the end .( between L3 and the barrier)

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

I support: lane introduced on the right, lane lost from the left. As found on the M25 in several places. Not only does it keep the majority of traffic moving better, but the middle lane owners club find themselves a lane to the left from where they thought they were going to be! It also matches the traffic density with the most packed lane splitting into two, and the most open lanes merging.

Having never been in L1 when the "crawler" lane ends , I can only speak from experience in L4 (in this case).

Good forward planning and observation when the warning comes up (of a return to 3 lanes), together with appropriate speed adjustment should aid a smooth and progressive change into L3. I always use an indication in good time with a corresponding adjustment of speed to let others in L3 know what my intentions are.

These actions may, of course, lead to a "zip-merging" debate.

And I swing both ways on that fecker................

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Simon

As most of the traffic in L1 and L2 in heavy traffic conditions will be lorries who are generally considerate and courteous to each other I would say it is safer to merge those lanes. There are several places where this happens, usually where L1 is designated as a Crawler Lane

On the contrary, where L4 merges into L3 in heavy traffic conditions, most of the traffic in L4 is impatient twats and I see a lot of people barreling up to the rumble strip and beyone then barging in front of someone with about 1' clearance.

Is this fair to the HGVs that they should have the extra hassle just because sales reps tend to drive idiots, not in the slightest, but there will be less accidents

As an added bonus, if you create an extra lane to the right, then remove a lane from the left a little later the more unobservent middle lane morons will end up dumped into L1 and will stay there for a while before they notice.

They should be like they are on the top side of the M25. You get a crawler lane at the bottom of two of this hills and then fizzles out back into lane 1 at the brow. It works well generally, speaking as a trucker.

What don't work are outside lane merges, lane 4 into lane 3. Two spring to mind here - the top of the M621 and the M62 eastbound at the top of Windy Hill. You can virtually guarantee it every time that some numpty will be in the next lane doing aboug half your speed and you've got to ease right off and drop in behind if you don't make it before the chevrons.

As long as they leave the crawler lanes a couple of hundred yards past the brows of the hills then crawler lane back into lane 1 works well for us truckers and prevents knacking up the fast lanes.

My 2p.

Although not strictly the same issue, the link below shows the eastbound merge of the M27 and M275 at Portsmouth. The outside lane of the M27 merges with the inside lane of the M275. Not my most favourite as visibility is also obstructed by varying levels and by barriers.

http://local.live.com/default.aspx?v=2& ... ne=4330960

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Malcolm W.
The views expressed in this post are personal opinions and do not represent the views of Safespeed.

I have always thought that the M27 M275 junction was very badly designed - as you say visibility is very poor, as due to elevation changes it is not possible to see anything until you are at the chevrons, and then the faster L2 traffic that has to merge with minimal warning. There is little "common sense" about it either, as the M27 traffic is continuing along the M27, but it is they that have to merge. I can only assume that the decision was based around peak traffic densities, but I have nearly been caught out a few times on it. It would be improved if there was a reasonable distance of 4 lanes that then merged, but I have learnt that the best way is to get into L1 for a stress free merge.

Thats funny as I used to use both stetches of Mway every day and thought they worked pretty well - there is plently of warning and I very rarely saw a big willy contest, perhaps because most drivers realised the speeds involved meant that if they didnt put safety first then its going to get nasty.

Its preferable then the wasted space, as Homer points out, and huge amounts of undertaking that occurs at J24W on the M62.