Junction review after wrong-way crash

[rhyds]

It’s logical, and makes sense, but I’m still not sure why it happens.

Then again, I sometimes used to choose the wrong gear by mistake (more when I was learning), probably because they sit close to each other (first, third/second, fourth).

It’s noticeable how Australia and New Zealand also remind drivers that they drive on the left, even though it’s quite common in Asia.

Its because you jump in to a car and drive how you normally do almost like a reflex action. A much less dangerous example is when I borrow my dad's Suzuki Grand Vitara. I know full well that on that car the wiper and indicator stalks are the other way around to every other car I've ever owned, yet still at least once on a journey I'll go for the wrong one.

[Ruperts Trooper]

It’s logical, and makes sense, but I’m still not sure why it happens.

Then again, I sometimes used to choose the wrong gear by mistake (more when I was learning), probably because they sit close to each other (first, third/second, fourth).

It’s noticeable how Australia and New Zealand also remind drivers that they drive on the left, even though it’s quite common in Asia.

Its because you jump in to a car and drive how you normally do almost like a reflex action. A much less dangerous example is when I borrow my dad's Suzuki Grand Vitara. I know full well that on that car the wiper and indicator stalks are the other way around to every other car I've ever owned, yet still at least once on a journey I'll go for the wrong one.

After decades of driving cars with indicators the "wrong" way round for RHD (talk to Aussies about it) I bought a Hyundai which had them the "right" way round for RHD - but even after nearly 5 years of ownership, I'd occasionally get it wrong.

[andrewwoods]

Bumping this back to the original topic - wrong way drivers on the M40 near J8

The Oxford Mail is reporting that new temporary signs will be installed by the services at J8A to help prevent drivers going the wrong way.
It does look (and is stated in the article) that the drivers possibly entered the A40 first at the tight bend just west of J8A (here), and then came onto the M40 itself at J8. That explanation certainly makes more sense for the caravan incident before Christmas.

Andrew

[Micro The Maniac]

The Oxford Mail is reporting that new temporary signs will be installed by the services at J8A to help prevent drivers going the wrong way.

Are they going to be red circles, with a central horizontal white line?

Like the ones already there?

[jimboLL]

The Oxford Mail is reporting that new temporary signs will be installed by the services at J8A to help prevent drivers going the wrong way.

Are they going to be red circles, with a central horizontal white line?

Like the ones already there?

Is there a reason why there isn't a keep left sign at the same point?

[Micro The Maniac]

Is there a reason why there isn't a keep left sign at the same point?

Eh? Keep left, while driving down the road they shouldn't be driving down?

Are they more likely to follow the "Keep left" than the "No Entry"?

What about all the "You're going the wrong way" signs they've also ignored (the plain grey ones, with nothing else on them - that conveniently provide somewhere to put ADSs on the back)

[Chris Bertram]

Is there a reason why there isn't a keep left sign at the same point?

Eh? Keep left, while driving down the road they shouldn't be driving down?

Are they more likely to follow the "Keep left" than the "No Entry"?

What about all the "You're going the wrong way" signs they've also ignored (the plain grey ones, with nothing else on them - that conveniently provide somewhere to put ADSs on the back)

That's a two-way slip road, part of the trumpet junction where A418 joins A40.

[Stevie D]

Is there a reason why there isn't a keep left sign at the same point?

Eh? Keep left, while driving down the road they shouldn't be driving down?

Are they more likely to follow the "Keep left" than the "No Entry"?

No, you put the "keep left" sign at the gore, where traffic is supposed to keep left to join the westbound A40 ... a bit like this: https://goo.gl/maps/twt1bPs2o7K2 ... and a "turn left ahead" sign on the approach to it

[Conekicker]

Bumping this back to the original topic - wrong way drivers on the M40 near J8

The Oxford Mail is reporting that new temporary signs will be installed by the services at J8A to help prevent drivers going the wrong way.
It does look (and is stated in the article) that the drivers possibly entered the A40 first at the tight bend just west of J8A (here), and then came onto the M40 itself at J8. That explanation certainly makes more sense for the caravan incident before Christmas.

Andrew

I'd hazard a guess that these will be worded signs of some sort. I'd strongly advise whoever is involved in this should very carefully read TSRGD and particularly Schedule 13, Part 9.

Otherwise, in the event of another incident, they might well be leaving themselves open to legal action.

[Johnathan404]

If they really believe that symbols or words would have stopped a likely wrong-way collision then I'm not going to object to the signs. Some painted arrows on the spur itself and the link road might be best. I just think it's unlikely.

Is there a reason why there isn't a keep left sign at the same point?

Eh? Keep left, while driving down the road they shouldn't be driving down?

Are they more likely to follow the "Keep left" than the "No Entry"?

What about all the "You're going the wrong way" signs they've also ignored (the plain grey ones, with nothing else on them - that conveniently provide somewhere to put ADSs on the back)

Old street view shows that there used to be chevrons at the split, but they look battered from several collisions and wiped out in 2016. I could have sworn there was once a 'keep left' arrow there too, but I could be wrong.

Battered signs at the split should be a huge clue that something is wrong. Obviously it means the sign is more likely to be missing one day when it is needed, but it's also telling you there is a long history of people getting the approach wrong and in an ideal world the road would be re-aligned.

I have reported on here before that the arrow here (coming down the hill) gets knocked flat about once every six months. As a little game you can go through Street View history mode (have to move around a bit first) and see how many times it was actually in place when GSV visited. Consequently I have seen people drive the wrong way when it isn't there. This approach clearly isn't working.

[Micro The Maniac]

Old street view shows that there used to be chevrons at the split, but they look battered from several collisions and wiped out in 2016. I could have sworn there was once a 'keep left' arrow there too, but I could be wrong.

Battered signs at the split should be a huge clue that something is wrong. Obviously it means the sign is more likely to be missing one day when it is needed, but it's also telling you there is a long history of people getting the approach wrong and in an ideal world the road would be re-aligned.

Fair point... but there is already a No Entry sign on the right at that point - plus a square, circular and triangular grey "you're going the wrong way" style signs I alluded to. Not only that, to have got here you have to drive quite a way the wrong side of solid double white lines.

I also suggest that damage to those signs, as with so many elsewhere, is merely people coming down the slip too fast and not making it around the bend...

[mikehindsonevans]

Old street view shows that there used to be chevrons at the split, but they look battered from several collisions and wiped out in 2016. I could have sworn there was once a 'keep left' arrow there too, but I could be wrong.

Battered signs at the split should be a huge clue that something is wrong. Obviously it means the sign is more likely to be missing one day when it is needed, but it's also telling you there is a long history of people getting the approach wrong and in an ideal world the road would be re-aligned.

Fair point... but there is already a No Entry sign on the right at that point - plus a square, circular and triangular grey "you're going the wrong way" style signs I alluded to. Not only that, to have got here you have to drive quite a way the wrong side of solid double white lines.

I also suggest that damage to those signs, as with so many elsewhere, is merely people coming down the slip too fast and not making it around the bend...

Perhaps this is a site where the local authority would win plaudits for lowering the speed limit with a real justification?

[Andy P]

Whilst there is obviously no excuse for entering the slip road in the wrong direction, I can understand why there is a small risk of it at this particular junction - when you first come round the bend, the off-slip can be clearly seen going straight ahead, and it is less clear at that point that the on-slip exists.

Obviously, the signage could and should be improved. In addition, I wonder if a physical carriageway separation extending a couple of hundred metres before the gore would be helpful.

[ais523]

Looking at the whole area on Street View, it was easy to get confused as to how the whole area worked. There are one-way and two-way roads mixed in close proximity, and a place where a road looks like a two-way slip road but you can turn across it at-grade! (If you do so, you end up on a one-way road that looks very similar to the two-way road you were just on, and inescapably leads to a motorway.)

Part of the recipe for confusion here is that there are two routes from the services to M40 southbound; you can either use the dumb-bell at J8A to join the motorway directly, or else turn left onto the A40 and left again at the trumpet, which is longer but freeflow. (The latter route isn't signed at the junction itself, but is signed immediately after you turn left.) If someone is attempting the latter route but then misses the turning at the trumpet, they'll then be on a two-way road while expecting to be on a 1-way road, see that the road splits ahead of them, and if they recognise that the left-hand half of the split joins the A40 in the direction they don't want to go, they'll take the right-hand half (which joins the M40 contrary to the flow of traffic). There are no-entry signs there but no other warnings not to use it (and the signs aren't even illuminated).

The offender here seems to be London Road; it's been given routes to the M40 southbound and A40 northbound that require crossing a sliproad in an otherwise free-flow junction at-grade. I think simplifying the junction would be a good idea on safety grounds if it could be done easily, but unfortunately, there don't seem to be many simplifications that could be made without either making minor movements impossible or making major movements much more difficult.

One simple improvement that would just require a bit of paint would be to place an arrow on each lane showing which direction the lane is going in. This is something that I've seen in many other places where it's easy to get confused about whether a road is one-way or two-way. (Road signs, of course, would also help; illuminate the no-entry signs, place a keep-left sign at the diverge, and place one-way or warning-two-way-traffic signs whenever the road changes between one-way and two-way.)

Just look at this view. The road to the left is one-way (and about to have traffic merge in from its right), with no indication of either. The road to the right is two-way, and if you use the right-hand lane against the flow of traffic, you will end up on the M40 against the flow of traffic. So the number of things that need to go wrong for a driver to be confused enough to cause a major incident are much lower here than they would be at most places in the motorway network.

[Johnathan404]

The low standard of this junction should not be a surprise to anybody who knows its history.

It was built in the early 1960s as a junction on the A40. To the west were LILOs and flat crossroads. The A418 to the north was the start of a long NSL S2, so traffic approaching from that direction would have much less doubt that it is single carriageway throughout. Motorway regulations were added to the road east of here much later.

On the main M40 and across the motorway network, tight 1960s and 1970s junctions have since been re-designed. This is one of the tightest 'true' trumpet junctions in the country, let alone one with motorway regulations involved. It has survived primarily because the completion of M40 J8a has made the motorway-facing slips totally redundant. They now only serve Wheatley, and Wheatley does not deserve direct access from the motorway network (versus a one mile detour).

If the layout is that dangerous, the solution is absolutely simple. Close the motorway-facing slip roads. They add nothing to the strategic road network. Even Google Street View has never bothered with them!

Just look at this view. The road to the left is one-way (and about to have traffic merge in from its right), with no indication of either. The road to the right is two-way, and if you use the right-hand lane against the flow of traffic, you will end up on the M40 against the flow of traffic. So the number of things that need to go wrong for a driver to be confused enough to cause a major incident are much lower here than they would be at most places in the motorway network.

That's not even the mistake I usually make. That direction sign on the right looks like something you would normally to find on the left-hand side of the road. Driving in poor visibility, it takes a little longer to notice that there is actually a sharp left-hand bend before the sign, and that you don't pass it on the right as you might expect.

The offender here seems to be London Road; it's been given routes to the M40 southbound and A40 northbound that require crossing a sliproad in an otherwise free-flow junction at-grade. I think simplifying the junction would be a good idea on safety grounds if it could be done easily, but unfortunately, there don't seem to be many simplifications that could be made without either making minor movements impossible or making major movements much more difficult.

Although as a point-of-interest the A40 eastbound off-slip is not free-flowing, although the carriageway alignment was clearly designed to be. The angle you join the A418 is not great, especially given that it's single carriageway, so the tarmac is covered in paint and signs to get you to slow down and stop.

Perhaps this is a site where the local authority would win plaudits for lowering the speed limit with a real justification?

Although the speed limit is officially 50 (Oxon NSL), there is an advisory 20, and if you do too much more you won't make it around the bend in the first place.

[Berk]

I’m just wondering if this is the main reason two-way slip roads are very seldom used in this country??

Compared with Spain, where they’re fairly common.

[fran_c_is]

On the main M40 and across the motorway network, tight 1960s and 1970s junctions have since been re-designed. This is one of the tightest 'true' trumpet junctions in the country, let alone one with motorway regulations involved. It has survived primarily because the completion of M40 J8a has made the motorway-facing slips totally redundant. They now only serve Wheatley, and Wheatley does not deserve direct access from the motorway network (versus a one mile detour).

Talking of tight junctions, there's the A405/M1 junction (M1 J6 Waterdale Interchange) for comparison - there are bollards on sections of the double white lines on the two-way slips. I don't know if there has been any history of wrong-way errors here (I expect these are just for discouraging speeding on the tight loops), but might bollards be of use at Wheatley? Having said that...

If the layout is that dangerous, the solution is absolutely simple. Close the motorway-facing slip roads. They add nothing to the strategic road network. Even Google Street View has never bothered with them!

...I think this closure suggestion is better.

[mikehindsonevans]

Here in Hampshire, both northbound on-ramp and southbound off-ramps at M3 j13 feature 180-degree bends.

The crucial difference is a concrete kerb (separating the n/b on from the n/b off) or proper Armco and a median strip (segregating s/b off from s/b on) between the head-on traffic flows.

The 30mph limit on the final 50yds of the northbound off-ramp didn't prevent a spectacular prang last November. This saw a (pursued by police) driver flying down the ramp, taking out two traffic-light poles and wrecking the house across Leigh Road when gravity finally caught up with him.

[Stevie D]

I’m just wondering if this is the main reason two-way slip roads are very seldom used in this country??

Compared with Spain, where they’re fairly common.

Pretty much, yes. They are now deprecated and should not be used for new "full slip road" junctions like this, although they can still be used for compact junctions where the angle of approach is different - there, you are approaching more at right angles, and so it is now obvious that you have to turn left, unlike here where as you are coming round the bend what you see first is the "wrong" road. New installations would have the lanes as physically separated carriageways.

I don't know how much difference there is if the trumpet faces the other way - it feels like there should be less risk of drivers going the wrong way, but whether there's any evidence for that I couldn't say.

[Jonathan B4027]

The low standard of this junction should not be a surprise to anybody who knows its history.

It was built in the early 1960s as a junction on the A40. To the west were LILOs and flat crossroads. The A418 to the north was the start of a long NSL S2, so traffic approaching from that direction would have much less doubt that it is single carriageway throughout. Motorway regulations were added to the road east of here much later.

On the main M40 and across the motorway network, tight 1960s and 1970s junctions have since been re-designed. This is one of the tightest 'true' trumpet junctions in the country, let alone one with motorway regulations involved. It has survived primarily because the completion of M40 J8a has made the motorway-facing slips totally redundant. They now only serve Wheatley, and Wheatley does not deserve direct access from the motorway network (versus a one mile detour).

If the layout is that dangerous, the solution is absolutely simple. Close the motorway-facing slip roads. They add nothing to the strategic road network. Even Google Street View has never bothered with them!

Opened in 1963 ish as part of the Wheatley bypass. Only reason it is tight is because the railway was still open at that point. The motorway restrictions were added in 1991 when the M40 extension opened, the original motorway started and ended abruptly without a junction around where J8 is now (the start/end of the Wheatley bypass as constructed). Remember that J8a was only north facing until the services opened in 1998.