Don't think we have a thread on these, this can hopefully tie in nicely with the "Botched Roadsigns" thread. (Can't really steal Chris' title "Bad Junctions" which might be slightly better, but still...)
So, basically, this thread is where you can discuss junctions which are bad. No notability or size requirements are needed, if it's there and it's a bit rubbish then you can mention it whether it's already on CBRD or not.
And of course, in the spirit of positivity, if you have any ideas how a terrible junction could be made better, again however small or large, then these are also welcome in this thread.
Discussion of botched junctions posted by others is not only allowed, but encouraged.
I'll add a few in a new post to get this started.
Botched Junctions
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ForestChav
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Botched Junctions
C, E flat and G go into a bar. The barman says "sorry, we don't serve minors". So E flat walks off, leaving C and G to share an open fifth between them.
Never argue with an idiot. They will bring you down to their level and beat you with experience.
Never argue with an idiot. They will bring you down to their level and beat you with experience.
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ForestChav
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- Posts: 11126
- Joined: Sat Sep 24, 2005 00:00
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Re: Botched Junctions
A453/A52
Was initially one bridge over the river, which terminated the ring road on the south bank by turning West towards Clifton, and linking up with Wilford Lane. Over time, parts have been added as the ring road was extended further round West Bridgford and the A453 through Clifton came later.
So... for traffic coming northbound over Clifton Bridge, and either staying on the A453 or A52, this works well, and you even have a nice little flyover at the northbound exit for the A453. You just stay in the lane you were initially, and you can do it (though A453 traffic wanting to use the flyover needs to be in the left hand lane).
That's where it ends. Every other major movement is bad.
Southbound traffic wanting to stay on the A453 or A52 needs to come on in 2 lanes then has a brief period where it needs to swap with traffic doing the opposite. It's like a zip the way traffic interacts, for example A453 traffic joining at the slip road needs to be in lanes 3 or 4 but comes on lanes 1 or 2.
The exit for the B679 from southbound traffic requires first moving onto the A453, then turning straight off, and isn't signed.
To move from the clockwise A52 to the southbound A453 (a major movement) you need to go off and borrow the roundabout between the B679 and A453 with a housing estate which must be almost impossible to get off at peak times. This should be free flow, but said estate blocks the movement off, so can't be, and the B679 junction is too close to the rest of it to make it merge with the A453.
Joining the anticlockwise A52 from the A453 on the south bank needs you to borrow a bit of the A453 then join a tiny slip road which feels like an afterthought.
I'm not sure though what might make this better aside from flattening it all and starting it again, and making the A453 and A52 run parallel over the river, with merging like when the A1 meets the M62, but you'd have the added complexity of doing it in an urban context and over a river...
Was initially one bridge over the river, which terminated the ring road on the south bank by turning West towards Clifton, and linking up with Wilford Lane. Over time, parts have been added as the ring road was extended further round West Bridgford and the A453 through Clifton came later.
So... for traffic coming northbound over Clifton Bridge, and either staying on the A453 or A52, this works well, and you even have a nice little flyover at the northbound exit for the A453. You just stay in the lane you were initially, and you can do it (though A453 traffic wanting to use the flyover needs to be in the left hand lane).
That's where it ends. Every other major movement is bad.
Southbound traffic wanting to stay on the A453 or A52 needs to come on in 2 lanes then has a brief period where it needs to swap with traffic doing the opposite. It's like a zip the way traffic interacts, for example A453 traffic joining at the slip road needs to be in lanes 3 or 4 but comes on lanes 1 or 2.
The exit for the B679 from southbound traffic requires first moving onto the A453, then turning straight off, and isn't signed.
To move from the clockwise A52 to the southbound A453 (a major movement) you need to go off and borrow the roundabout between the B679 and A453 with a housing estate which must be almost impossible to get off at peak times. This should be free flow, but said estate blocks the movement off, so can't be, and the B679 junction is too close to the rest of it to make it merge with the A453.
Joining the anticlockwise A52 from the A453 on the south bank needs you to borrow a bit of the A453 then join a tiny slip road which feels like an afterthought.
I'm not sure though what might make this better aside from flattening it all and starting it again, and making the A453 and A52 run parallel over the river, with merging like when the A1 meets the M62, but you'd have the added complexity of doing it in an urban context and over a river...
C, E flat and G go into a bar. The barman says "sorry, we don't serve minors". So E flat walks off, leaving C and G to share an open fifth between them.
Never argue with an idiot. They will bring you down to their level and beat you with experience.
Never argue with an idiot. They will bring you down to their level and beat you with experience.
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ForestChav
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Re: Botched Junctions
A34/A303/A30
Yes, the junction where the main route from London to the South West meets one from the South coast to the Midlands. And the A30 joins the party too, borrowing a bit of old A43 to make it. Sadly the pub isn't there, because you might need it...
Fortunately, because this forms a triangle with the M3, some of the load is lessened off this junction by the M3 catering for them. One which doesn't, and is required to work well here because of the restrictions at the A303/M3 junction, is A43N - A303W because traffic from Winchester and Southampton wanting to head for the westbound A303 can't head up the M3. This freeflow movement is the only one you don't need to use the A30 for, though the movement is catered for on this if you really want to... Good example of redundancy, but having this movement on there would probably overload it, so it's fortunate it has its own provision.
Of the remaining four slip roads joining the A30 (it's not really a gyratory, since it doesn't go all the way round) 3 of them meet it at a roundabout, though there are only two roundabouts. The slip roads onto the WB A303 meet the A30 at a give way, and those from the A34 NB and A303 EB meet it at the same roundabout, where the A30 stops. These two factors cause issues because they conflict major movements
- heading from A303 EB to A34 NB should be easy. You leave the A303, then at the first roundabout turn onto the A34. However... there is no advanced signage at the roundabout advising which way is for Winchester and which is for Newbury, so unless you've looked in advance, you would perhaps think that Winchester is right and Newbury left, since that's the overall direction you're ending up in. But it's not, it's the other way round: and since the only indication you get of this is a tiny "Newbury A34" sign, which is on the opposite end of the roundabout to where you join, and is partially obscured by such, AND because that means you need to approach in the right lane - Loads of people must get this wrong.
- A303 EB to A34 SB would work well despite this, since you just follow the A30 round the junction and turn onto the A34 at the end. You'd be relatively unimpeded doing this because the only conflicting movement, as with any other traffic leaving the A303 here, is covered by the M3.
- the remaining major movement, A34 SB to A303 WB, would superficially appear to work fine; come off the A34, turn left, use a bit of the A30 then join the A303, without doing much distance. However, you then have to turn right, and give way to anything going from the EB A303 onto the A34. So you have your wires effectively crossed with people going the opposite way. There's also no buffer for right turning traffic, but this would really only hold up people effectively making a u-turn, or traffic heading off the A34 onto the A303 towards the M3, which can't be too much of a movement because longer distance the M4 covers this (as you can only go London bound onto the M3 there).
This junction's saved most of the issues by the fact that most of the traffic doesn't turn off here, and that the M3 is close by to cover some of its work. So, you don't really need to do an awful lot to make it better, apart from the following two things
1. get rid of the right turn and replace it with a mini roundabout. There's the space and then the right turning traffic would have priority.
2. Advanced signage of the roundabout when leaving the eastbound A303 saying you have to go right to turn left and vice versa
Yes, the junction where the main route from London to the South West meets one from the South coast to the Midlands. And the A30 joins the party too, borrowing a bit of old A43 to make it. Sadly the pub isn't there, because you might need it...
Fortunately, because this forms a triangle with the M3, some of the load is lessened off this junction by the M3 catering for them. One which doesn't, and is required to work well here because of the restrictions at the A303/M3 junction, is A43N - A303W because traffic from Winchester and Southampton wanting to head for the westbound A303 can't head up the M3. This freeflow movement is the only one you don't need to use the A30 for, though the movement is catered for on this if you really want to... Good example of redundancy, but having this movement on there would probably overload it, so it's fortunate it has its own provision.
Of the remaining four slip roads joining the A30 (it's not really a gyratory, since it doesn't go all the way round) 3 of them meet it at a roundabout, though there are only two roundabouts. The slip roads onto the WB A303 meet the A30 at a give way, and those from the A34 NB and A303 EB meet it at the same roundabout, where the A30 stops. These two factors cause issues because they conflict major movements
- heading from A303 EB to A34 NB should be easy. You leave the A303, then at the first roundabout turn onto the A34. However... there is no advanced signage at the roundabout advising which way is for Winchester and which is for Newbury, so unless you've looked in advance, you would perhaps think that Winchester is right and Newbury left, since that's the overall direction you're ending up in. But it's not, it's the other way round: and since the only indication you get of this is a tiny "Newbury A34" sign, which is on the opposite end of the roundabout to where you join, and is partially obscured by such, AND because that means you need to approach in the right lane - Loads of people must get this wrong.
- A303 EB to A34 SB would work well despite this, since you just follow the A30 round the junction and turn onto the A34 at the end. You'd be relatively unimpeded doing this because the only conflicting movement, as with any other traffic leaving the A303 here, is covered by the M3.
- the remaining major movement, A34 SB to A303 WB, would superficially appear to work fine; come off the A34, turn left, use a bit of the A30 then join the A303, without doing much distance. However, you then have to turn right, and give way to anything going from the EB A303 onto the A34. So you have your wires effectively crossed with people going the opposite way. There's also no buffer for right turning traffic, but this would really only hold up people effectively making a u-turn, or traffic heading off the A34 onto the A303 towards the M3, which can't be too much of a movement because longer distance the M4 covers this (as you can only go London bound onto the M3 there).
This junction's saved most of the issues by the fact that most of the traffic doesn't turn off here, and that the M3 is close by to cover some of its work. So, you don't really need to do an awful lot to make it better, apart from the following two things
1. get rid of the right turn and replace it with a mini roundabout. There's the space and then the right turning traffic would have priority.
2. Advanced signage of the roundabout when leaving the eastbound A303 saying you have to go right to turn left and vice versa
C, E flat and G go into a bar. The barman says "sorry, we don't serve minors". So E flat walks off, leaving C and G to share an open fifth between them.
Never argue with an idiot. They will bring you down to their level and beat you with experience.
Never argue with an idiot. They will bring you down to their level and beat you with experience.
Re: Botched Junctions
I wrote a fairly long Bad Junctions application to CBRD about Selly Oak Triangle (A38/B384/A4040). It has been one of the worst junctions in Birmingham for years, and is truly bad at the moment.
At least one of the problems I mentioned has since been fixed, and there's a consultation for a proper fix to the whole thing going on at the moment. However, if anyone's interested, I can try to dig my report out.
On a side note, I actually went around all the road signs at Selly Oak Triangle a while back, and they were almost all incorrect. Here's my favourite of the botches (this is one of the ones which has since been fixed, but your guess is as good as mine as to what's going on here):
At least one of the problems I mentioned has since been fixed, and there's a consultation for a proper fix to the whole thing going on at the moment. However, if anyone's interested, I can try to dig my report out.
On a side note, I actually went around all the road signs at Selly Oak Triangle a while back, and they were almost all incorrect. Here's my favourite of the botches (this is one of the ones which has since been fixed, but your guess is as good as mine as to what's going on here):
Re: Botched Junctions
This has been covered on CBRD already but A34-A40-Oxford
Soooo many conflicted movements squeezed into a junction which attempts to squeeze everything from the A40 along with the main road into Oxford and with local accesses to Wolvercote and Five Mile drive to create a roundabout where you have to close your eyes an pull out if you want to go between a key route between Southampton and the main between between Gloucester and the West Countryy.
Made even worse between you have a random stretch of S2 between and Witney and D2 carrriageway, plus the fact that the viaduct was recently rebuilt apparently with the budget for a temporary third viaduct but not the room for even the most basic dumbbell junction between the A34 and A40.
Those sitting in the massive queues every morning on the A40(E) can confirm this is hardly the gateway to apparently our worldwide #1 university city,
Soooo many conflicted movements squeezed into a junction which attempts to squeeze everything from the A40 along with the main road into Oxford and with local accesses to Wolvercote and Five Mile drive to create a roundabout where you have to close your eyes an pull out if you want to go between a key route between Southampton and the main between between Gloucester and the West Countryy.
Made even worse between you have a random stretch of S2 between and Witney and D2 carrriageway, plus the fact that the viaduct was recently rebuilt apparently with the budget for a temporary third viaduct but not the room for even the most basic dumbbell junction between the A34 and A40.
Those sitting in the massive queues every morning on the A40(E) can confirm this is hardly the gateway to apparently our worldwide #1 university city,
I didn't want to believe my Dad was stealing from his job as a road worker. But when I got home, all the signs were there.
Re: Botched Junctions
A38/A358 at Creech Castle, Taunton, Somerset
The A38/A358 Toneway was originally a fairly fast D2 road to help traffic travel between M5 J25 and the centre of Taunton. It was slowed down by a few roundabouts along the way.
However, in the 1990s, a kneejerk reaction to an accident at the roundabout at Creech Castle resulted in the junction being downgraded into a signalised crossroads. It was horribly congested even at its opening, and is now barely usable when there's any kind of traffic on the roads.
The remaining roundabouts on the Toneway are busy, but far better flowing than this. Somerset CC were actually looking at grade separating it, but that was before the 2009 downturn so I'm guessing it's long gone from the agenda.
The A38/A358 Toneway was originally a fairly fast D2 road to help traffic travel between M5 J25 and the centre of Taunton. It was slowed down by a few roundabouts along the way.
However, in the 1990s, a kneejerk reaction to an accident at the roundabout at Creech Castle resulted in the junction being downgraded into a signalised crossroads. It was horribly congested even at its opening, and is now barely usable when there's any kind of traffic on the roads.
The remaining roundabouts on the Toneway are busy, but far better flowing than this. Somerset CC were actually looking at grade separating it, but that was before the 2009 downturn so I'm guessing it's long gone from the agenda.
Re: Botched Junctions
A1(M) J9: just a minor annoyance here but frustrating because it seems like it would have been easier to do it right!
On the northbound offslip there are three lanes. The righthand two lanes are for the A505(E) and these are controlled by traffic lights: this part actually works pretty well. The problem is with the left lane for the A505(W) into Letchworth. Although this lane bypasses the lights (there is an island separating it from the roundabout), it still has to give way to the traffic coming off the roundabout a little further on. But this give way is at such a shallow angle that it's difficult to see properly, and the traffic coming off the roundabout is going quite fast, making it difficult to get out. So many people have worked out that it's easier to get in the middle lane and go through the lights in order to get priority. And that just makes it harder for people in the "correct" lane to get out.
Maybe uncontrolled left-turn filter lanes have a place, but this one just doesn't work. If they'd just made all three lanes stop at the lights, everything would have been fine, and it would take up less space as well.
On the northbound offslip there are three lanes. The righthand two lanes are for the A505(E) and these are controlled by traffic lights: this part actually works pretty well. The problem is with the left lane for the A505(W) into Letchworth. Although this lane bypasses the lights (there is an island separating it from the roundabout), it still has to give way to the traffic coming off the roundabout a little further on. But this give way is at such a shallow angle that it's difficult to see properly, and the traffic coming off the roundabout is going quite fast, making it difficult to get out. So many people have worked out that it's easier to get in the middle lane and go through the lights in order to get priority. And that just makes it harder for people in the "correct" lane to get out.
Maybe uncontrolled left-turn filter lanes have a place, but this one just doesn't work. If they'd just made all three lanes stop at the lights, everything would have been fine, and it would take up less space as well.
Re: Botched Junctions
I'll also nominate M11 J12.
This might look like a fairly standard dumbbell, but if you're coming off the M11 southbound, you first have to merge with a minor road from Coton, with the minor road having priority. This is completely unexpected: the geometry is such that you can see the roundabout straight ahead of you, and it's all too easy to think that the give way signs are referring to that junction. I've twice been a passenger in a car with a driver seeing this junction for the first time, and each time - despite my warning - they've ended up flying out onto the minor road without looking, not realising the junction was there. It's just fortunate that the Coton road is quiet.
This problem wouldn't have been too hard to avoid. They could extend the offslip all the way to the roundabout so that it doesn't have to meet the minor road first. Or just fix the geometry so that the offslip meets the minor road at something closer to a right angle, and then you can't miss it.
This isn't the only problem with the junction: there's also the combination of a huge, fast roundabout and a fairly busy two-way cycle lane that crosses the arm just one car-length before the roundabout. This doesn't feel safe in the car (if you wanted to check for suicidal cyclists you'd have to be looking in three completely different places at once) so I wouldn't fancy trying it on the bike.
This might look like a fairly standard dumbbell, but if you're coming off the M11 southbound, you first have to merge with a minor road from Coton, with the minor road having priority. This is completely unexpected: the geometry is such that you can see the roundabout straight ahead of you, and it's all too easy to think that the give way signs are referring to that junction. I've twice been a passenger in a car with a driver seeing this junction for the first time, and each time - despite my warning - they've ended up flying out onto the minor road without looking, not realising the junction was there. It's just fortunate that the Coton road is quiet.
This problem wouldn't have been too hard to avoid. They could extend the offslip all the way to the roundabout so that it doesn't have to meet the minor road first. Or just fix the geometry so that the offslip meets the minor road at something closer to a right angle, and then you can't miss it.
This isn't the only problem with the junction: there's also the combination of a huge, fast roundabout and a fairly busy two-way cycle lane that crosses the arm just one car-length before the roundabout. This doesn't feel safe in the car (if you wanted to check for suicidal cyclists you'd have to be looking in three completely different places at once) so I wouldn't fancy trying it on the bike.
Re: Botched Junctions
There seem to be plans to apply for funding for improvement of the Creech Castle junction as 'Toneway Corridor Phase 1'. See here. The proposed budget suggests grade separation is not on the cards.M5Lenzar wrote:A38/A358 at Creech Castle, Taunton, Somerset
The A38/A358 Toneway was originally a fairly fast D2 road to help traffic travel between M5 J25 and the centre of Taunton. It was slowed down by a few roundabouts along the way.
However, in the 1990s, a kneejerk reaction to an accident at the roundabout at Creech Castle resulted in the junction being downgraded into a signalised crossroads. It was horribly congested even at its opening, and is now barely usable when there's any kind of traffic on the roads.
The remaining roundabouts on the Toneway are busy, but far better flowing than this. Somerset CC were actually looking at grade separating it, but that was before the 2009 downturn so I'm guessing it's long gone from the agenda.
Re: Botched Junctions
There have been some very bad accidents on that roundabout usually involving motorcyclists and cyclists. The situation is actually made worse because the ludicrous decision to make J13 a half junction where you cannot get onto the M11 norhbound or off it southbound. This results in a LOT of people going down to J12 and going round both roundabouts to get to where they need to go. This REALLY should have been fixed when they built the Madingley Road Park and Ride but once the new Cambridge West development is complete it will become a nightmare.dcrc2 wrote:I'll also nominate M11 J12.
This might look like a fairly standard dumbbell, but if you're coming off the M11 southbound, you first have to merge with a minor road from Coton, with the minor road having priority. This is completely unexpected: the geometry is such that you can see the roundabout straight ahead of you, and it's all too easy to think that the give way signs are referring to that junction. I've twice been a passenger in a car with a driver seeing this junction for the first time, and each time - despite my warning - they've ended up flying out onto the minor road without looking, not realising the junction was there. It's just fortunate that the Coton road is quiet.
This problem wouldn't have been too hard to avoid. They could extend the offslip all the way to the roundabout so that it doesn't have to meet the minor road first. Or just fix the geometry so that the offslip meets the minor road at something closer to a right angle, and then you can't miss it.
This isn't the only problem with the junction: there's also the combination of a huge, fast roundabout and a fairly busy two-way cycle lane that crosses the arm just one car-length before the roundabout. This doesn't feel safe in the car (if you wanted to check for suicidal cyclists you'd have to be looking in three completely different places at once) so I wouldn't fancy trying it on the bike.
Re: Botched Junctions
Easy answer for me. The £10m Black Dam M3 J6 Junction is, in my humble opinion, definitely botched. Not only through the general niggles of the junction itself, but the fact that it was designed to increase capacity which was not subsequently supported in the surrounding network. To provide some detail - and how I'd fix it, of course!
Southbound - A339 to M3. This was one of the major factors behind the new junction, congestion, particularly at the evening peak. beforehand, evening queues could reach from the junction to the A33. Today, they can reach from the junction to, um, the A33....
The project page and all consultation documents stated (and still state) that there would be three lanes from Black Dam to the M3 J6 roundabout. All the documentation officially issued carefully excluded the fact that this wasn't the case and that those promised three lanes would shrink back to the original two. Those two lanes are marked as follows: Lane 1 - London, Lane 2 - South West, these markings are on road markings only, there is no road side signage to indicate.
What happens? Firstly, as you approach Black Dam, Lane 1 on the A339 flows naturally into Lane 2 on the junction itself, staying in Lane 1 requires a good jink to the left. The result is that a lot of M3 northbound traffic ends up - sometimes accidently, often deliberately - in lane 2 on the junction and spur. So this traffic then merges - sometimes carefully, often with no concern of other users - back into Lane 1. In morning and afternoon peaks, this results in traffic slowing down to a near stop in Lane 1. Canny drivers simply burn up the Lane 2 and shoot up the northbound sliproad - whether they hope no-one attempts to immediately move out to overtake slow lorries etc. on the sliproad is an unknown.
What needs to happen? How about we get what the Highways Agency said they would deliver, i.e. three lanes the full length? Lane 1 and 2 can go north, lanes 2 and 3 can go south. I have been told that this can't be done because the northbound slip road cannot support the two lanes of traffic it is marked out for.... I guess the real issue is where the slip road joins the main carriageway - but perhaps that needs money too?
South westbound - A339 to A30. The A30 exit westbound matches the M3 exit for lanes - there are 3 coming off the junction, soon merging to 2. Despite this, traffic seems unable at busy periods to properly use all three lanes fully, it appears that if Lane 1 queues up too much, it blocks the others. Also, traffic stopped at the lights backs up around the junction blocking those using Lane 3 for the M3 and also blocks the A30-A339 access road. If you are in Lane 1 for the A30, held at the lights and at the back of the queue, thus exposed to southbound traffic speeding past, you feel VERY vulnerable.
What needs to happen? No idea, this whole section seems to have been bodged up good and proper!
Westbound - A30 to A30/A339. The westbound A30 from Hook splits two ways as it approaches Black Dam. To the left, two lanes are from the M3 and the A30. This is one of the few bits that works OK.
To the right, two lanes are for the Town Centre and for the A339. This two lane stretch crosses the southbound carriageway and heads onto four lane northbound A339. Yet the road markings are laid out so that Lane 1 is for the town centre, Lane 2 is for the A339. So, Lane 1 feeds into Lane 1 and 2 of the northbound carriageway, Lane 2 into lane 3 and 4.
What happens? Pretty predictable really, the bulk of the traffic is heading north on the A339 and so queues up in Lane 2. Once you have more than 4 cars in front of you, it'll take you 2 turns of the lights to get through. Most of this traffic naturally flows into Lane 4 on the northbound carriageway - lane markings actually guide you to Lane 3. And, of course, a good 50% of the traffic in Lane 2 will either cut you up at that point or push in further up.
What needs to happen? In my simple mind, why can both lanes not feed the A339 and town centre traffic can pull across from lane 1? Not that difficult, surely?
Eastbound - A30 to A30/A339 (Also south to the M3). Approaching from the east, lanes again split into two. Three lanes on the right feed the A30 and the M3. The A30 bit works OK. The M3 bit doesn't, I've done it a couple of times and despite my best efforts still seem to end up in the wrong lane - even following markings!
The A30 to the A339 bit is the troublesome bit and it essentially replicates the same scenario as the westbound, so the solution must surely be the same?
Northbound - M3 to A339. Works OK, however let's note that the original two lanes from the M3 to the A339 has been replaced by, er, two lanes. Capacity to the town centre was increased from 1 to 2 lanes - a lot of the traffic uses these lanes to undertake A339 traffic and move in further up. Also, A30 westbound and eastbound traffic is served by two tiny slip roads just before the junction.
In general, the layout restricts the traffic flow, the light phasing really damages traffic flows southbound, eastbound, westbound but - inexplicably - not really northbound!
After the chaos this caused Basingstoke, we have more to come. The A339/A33 junction improvements have already been screwed up and postponed (electrical cable found where it shouldn't be. Again) and work is about to start on the A30 Winchester Road Roundabout. Needless to say, local residents are not confident about this being delivered on time or budget.
Southbound - A339 to M3. This was one of the major factors behind the new junction, congestion, particularly at the evening peak. beforehand, evening queues could reach from the junction to the A33. Today, they can reach from the junction to, um, the A33....
The project page and all consultation documents stated (and still state) that there would be three lanes from Black Dam to the M3 J6 roundabout. All the documentation officially issued carefully excluded the fact that this wasn't the case and that those promised three lanes would shrink back to the original two. Those two lanes are marked as follows: Lane 1 - London, Lane 2 - South West, these markings are on road markings only, there is no road side signage to indicate.
What happens? Firstly, as you approach Black Dam, Lane 1 on the A339 flows naturally into Lane 2 on the junction itself, staying in Lane 1 requires a good jink to the left. The result is that a lot of M3 northbound traffic ends up - sometimes accidently, often deliberately - in lane 2 on the junction and spur. So this traffic then merges - sometimes carefully, often with no concern of other users - back into Lane 1. In morning and afternoon peaks, this results in traffic slowing down to a near stop in Lane 1. Canny drivers simply burn up the Lane 2 and shoot up the northbound sliproad - whether they hope no-one attempts to immediately move out to overtake slow lorries etc. on the sliproad is an unknown.
What needs to happen? How about we get what the Highways Agency said they would deliver, i.e. three lanes the full length? Lane 1 and 2 can go north, lanes 2 and 3 can go south. I have been told that this can't be done because the northbound slip road cannot support the two lanes of traffic it is marked out for.... I guess the real issue is where the slip road joins the main carriageway - but perhaps that needs money too?
South westbound - A339 to A30. The A30 exit westbound matches the M3 exit for lanes - there are 3 coming off the junction, soon merging to 2. Despite this, traffic seems unable at busy periods to properly use all three lanes fully, it appears that if Lane 1 queues up too much, it blocks the others. Also, traffic stopped at the lights backs up around the junction blocking those using Lane 3 for the M3 and also blocks the A30-A339 access road. If you are in Lane 1 for the A30, held at the lights and at the back of the queue, thus exposed to southbound traffic speeding past, you feel VERY vulnerable.
What needs to happen? No idea, this whole section seems to have been bodged up good and proper!
Westbound - A30 to A30/A339. The westbound A30 from Hook splits two ways as it approaches Black Dam. To the left, two lanes are from the M3 and the A30. This is one of the few bits that works OK.
To the right, two lanes are for the Town Centre and for the A339. This two lane stretch crosses the southbound carriageway and heads onto four lane northbound A339. Yet the road markings are laid out so that Lane 1 is for the town centre, Lane 2 is for the A339. So, Lane 1 feeds into Lane 1 and 2 of the northbound carriageway, Lane 2 into lane 3 and 4.
What happens? Pretty predictable really, the bulk of the traffic is heading north on the A339 and so queues up in Lane 2. Once you have more than 4 cars in front of you, it'll take you 2 turns of the lights to get through. Most of this traffic naturally flows into Lane 4 on the northbound carriageway - lane markings actually guide you to Lane 3. And, of course, a good 50% of the traffic in Lane 2 will either cut you up at that point or push in further up.
What needs to happen? In my simple mind, why can both lanes not feed the A339 and town centre traffic can pull across from lane 1? Not that difficult, surely?
Eastbound - A30 to A30/A339 (Also south to the M3). Approaching from the east, lanes again split into two. Three lanes on the right feed the A30 and the M3. The A30 bit works OK. The M3 bit doesn't, I've done it a couple of times and despite my best efforts still seem to end up in the wrong lane - even following markings!
The A30 to the A339 bit is the troublesome bit and it essentially replicates the same scenario as the westbound, so the solution must surely be the same?
Northbound - M3 to A339. Works OK, however let's note that the original two lanes from the M3 to the A339 has been replaced by, er, two lanes. Capacity to the town centre was increased from 1 to 2 lanes - a lot of the traffic uses these lanes to undertake A339 traffic and move in further up. Also, A30 westbound and eastbound traffic is served by two tiny slip roads just before the junction.
In general, the layout restricts the traffic flow, the light phasing really damages traffic flows southbound, eastbound, westbound but - inexplicably - not really northbound!
After the chaos this caused Basingstoke, we have more to come. The A339/A33 junction improvements have already been screwed up and postponed (electrical cable found where it shouldn't be. Again) and work is about to start on the A30 Winchester Road Roundabout. Needless to say, local residents are not confident about this being delivered on time or budget.
Re: Botched Junctions
I don't know what it's like when it's really busy there, so a tentative suggestion of Apex Corner in London. For a few years now there has been a freelow left filter lane so southbound A1 traffic can avoid the roundabout, which seems, and well may be, a sensible idea. Trouble is it means all s/b A1 traffic has to cram into Lane 1 of the 3 lane approach, where I have witnessed significant queueing before you get to the filter lane whilst the other two lanes have hardly anything in them. This arrangement doesn't seem to make the most of the available road space.
I can't really think of how you would sort it though without making the slip road 2-lane but as the A1 after here is only D2 you would still have a problematic merge to deal with. But was it better how it was originally?
I can't really think of how you would sort it though without making the slip road 2-lane but as the A1 after here is only D2 you would still have a problematic merge to deal with. But was it better how it was originally?
Re: Botched Junctions
I'm not convinced there's room to do the former, and it also introduces a fifth place the cycle lane has to give way. I agree it's unsafe, but I'd move the minor road instead and make it give way to the sliproad, possibly introducing sensor-controlled traffic lightsdcrc2 wrote:I'll also nominate M11 J12.
This might look like a fairly standard dumbbell, but if you're coming off the M11 southbound, you first have to merge with a minor road from Coton, with the minor road having priority. This is completely unexpected: the geometry is such that you can see the roundabout straight ahead of you, and it's all too easy to think that the give way signs are referring to that junction. I've twice been a passenger in a car with a driver seeing this junction for the first time, and each time - despite my warning - they've ended up flying out onto the minor road without looking, not realising the junction was there. It's just fortunate that the Coton road is quiet.
This problem wouldn't have been too hard to avoid. They could extend the offslip all the way to the roundabout so that it doesn't have to meet the minor road first. Or just fix the geometry so that the offslip meets the minor road at something closer to a right angle, and then you can't miss it.
I cycle this one regularly and from that point of view this roundabout isn't too bad: lots of visibility and if you time things right you can get across the roads and clear at reasonable speed: better than most of the other M11/A14 crossings. The problem is more the western roundabout, particularly when heading into town, where you are guaranteed to have to stop and don't have much advance notice of traffic coming through.This isn't the only problem with the junction: there's also the combination of a huge, fast roundabout and a fairly busy two-way cycle lane that crosses the arm just one car-length before the roundabout. This doesn't feel safe in the car (if you wanted to check for suicidal cyclists you'd have to be looking in three completely different places at once) so I wouldn't fancy trying it on the bike.
For drivers it's not too bad IF you know there's a crossing there, and my recollection is that the signage isn't too great from some directions.
[real name Colin]
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lefthandedspanner
- Member
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- Joined: Thu Aug 20, 2015 21:25
- Location: West Yorkshire
Re: Botched Junctions
M55 junction 4 (the western terminus), though it's not the junction itself that's the botched bit but the eastbound carriageway on the mainline.
The motorway starts after the exit sliproad and initially has two lanes. It briefly narrows down to one lane underneath the junction (with the right lane hatched out), then the two lanes of the entry sliproad merge from the left, leaving you in the outside lane and automatically breaking the law if you're towing a driving a HGV. If you're not familiar with the area, it's a total "you what?" moment.
The M55 as a whole also qualifies for Botched Driver Location data: junction numbers normally increase along the A carriageway and decrease along the B carriageway, but on the M55 it's the other way round.
The motorway starts after the exit sliproad and initially has two lanes. It briefly narrows down to one lane underneath the junction (with the right lane hatched out), then the two lanes of the entry sliproad merge from the left, leaving you in the outside lane and automatically breaking the law if you're towing a driving a HGV. If you're not familiar with the area, it's a total "you what?" moment.
The M55 as a whole also qualifies for Botched Driver Location data: junction numbers normally increase along the A carriageway and decrease along the B carriageway, but on the M55 it's the other way round.
Re: Botched Junctions
The end of the M55 is a bit of a historical accident, caused by the fact that when it opened in 1975, there was nothing really beyond J4. The route in those days was always via the A583, hence the two lane entry onto the M55.
The law gives a reasonable distance for HGVs to sort themselves out; although I think in 1975 many of the right hand lane restrictions didn't exist, the Highway Code cites the Motorways (England & Wales) Traffic Regulations 1982 for the current rules.
The law gives a reasonable distance for HGVs to sort themselves out; although I think in 1975 many of the right hand lane restrictions didn't exist, the Highway Code cites the Motorways (England & Wales) Traffic Regulations 1982 for the current rules.
Bryn
Terminally cynical, unimpressed, and nearly Middle Age already.
She said life was like a motorway; dull, grey, and long.
Blog - https://showmeasign.online/
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Terminally cynical, unimpressed, and nearly Middle Age already.
She said life was like a motorway; dull, grey, and long.
Blog - https://showmeasign.online/
X - https://twitter.com/ShowMeASignBryn
YouTube - https://www.youtube.com/@BrynBuck
Re: Botched Junctions
Maybe the double lane gain made sense once upon a time but that doesn't explain why it's not been reduced to a single lane gain since 1975. Presumably there have been resurfacings etc but the opportunity to replace the outdated markings was not taken.
Re: Botched Junctions
The A534 at Crewe Green is a definite botch, installed by Cheshire CC and now about to have its second iteration installed by Cheshire East !
Question is why are we so good at botching when it comes to road junctions ? Is it all down to finance, surely not ?
Question is why are we so good at botching when it comes to road junctions ? Is it all down to finance, surely not ?
Re: Botched Junctions
The A4/A46 junction has been mentioned elsewhere. It's great it you're going from the M4 to Bradford-on-Avon or Box. The problem is that the overwhelming majority of the traffic is either going from the M4 to Bath, or from Bradford-on-Avon/Box to Bath.
The result? Dreadful convergence of what is, in effect, four lanes of dual carriageway traffic into one single lane on London Road (A4).
The result? Dreadful convergence of what is, in effect, four lanes of dual carriageway traffic into one single lane on London Road (A4).
Re: Botched Junctions
That said the flows are still mainly from the A583. I've never in my life experienced congestion.jackal wrote:Maybe the double lane gain made sense once upon a time but that doesn't explain why it's not been reduced to a single lane gain since 1975. Presumably there have been resurfacings etc but the opportunity to replace the outdated markings was not taken.
Bryn
Terminally cynical, unimpressed, and nearly Middle Age already.
She said life was like a motorway; dull, grey, and long.
Blog - https://showmeasign.online/
X - https://twitter.com/ShowMeASignBryn
YouTube - https://www.youtube.com/@BrynBuck
Terminally cynical, unimpressed, and nearly Middle Age already.
She said life was like a motorway; dull, grey, and long.
Blog - https://showmeasign.online/
X - https://twitter.com/ShowMeASignBryn
YouTube - https://www.youtube.com/@BrynBuck
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SouthWest Philip
- Member
- Posts: 3483
- Joined: Sun Mar 31, 2002 19:35
- Location: Evesham, Worcestershire
Re: Botched Junctions
Was a more substantial road originally intended as the westward extension from the M55? Perhaps there was an intention at one stage for the M55 to make it to the town centre car parks/coast?Bryn666 wrote:That said the flows are still mainly from the A583. I've never in my life experienced congestion.jackal wrote:Maybe the double lane gain made sense once upon a time but that doesn't explain why it's not been reduced to a single lane gain since 1975. Presumably there have been resurfacings etc but the opportunity to replace the outdated markings was not taken.