Australian road markings

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Peter Freeman
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Australian road markings

Post by Peter Freeman » Thu Sep 17, 2020 14:14

Bryn666 wrote:
Mon Sep 07, 2020 15:47
We could learn a lot from Australian road markings.
I'm sure there's stuff we could still learn from UK to be fair - but not intersection or interchange design. In Melbourne we build fully signalised channelized intersections AND roundabouts from new, but not roundabouts for heavy flows. There's a constant turnover of roundabout-to-channelized conversions, in both Melbourne Sydney. Here are some examples of typical layouts on our outer suburban (not limited access) roads.

These five are from the just-starting-up Fitzsimons Lane upgrade:
https://roadprojects.vic.gov.au/__data/ ... _large.jpg
https://roadprojects.vic.gov.au/__data/ ... _large.jpg

Plenty Road upgrade:
https://mrpv.ucapp.com.au/plenty_road_upgrade/

(edited to remove dead links)
Last edited by Peter Freeman on Sat May 29, 2021 15:05, edited 2 times in total.

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Vierwielen
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Re: Australian road markings

Post by Vierwielen » Thu Sep 17, 2020 21:34

To be fair, you guys in Oz have a lot more land and also much of suburbia was laid out after the car became commonplace.

One of the things that I did notice when I was in Perth a few years ago was the number of people who had their house number painted in large characters on their drive. It made navigating much easier!

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Re: Australian road markings

Post by linuxrocks » Fri Sep 18, 2020 10:37

One thing that I miss from Australia, are the street names signs. Here in the UK, often they are only on one side of the road, and/or one end of a road. They are also very low down, so if a car is parked in front of it, which always seems to happen to me, they you miss it.

UK example: https://www.google.co.uk/maps/@53.78908 ... 384!8i8192

Aussie example: https://www.google.com.au/maps/@-35.019 ... 312!8i6656

More typical Aussie example (my mothers road): https://www.google.co.uk/maps/@-34.8607 ... 312!8i6656

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Gareth
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Re: Australian road markings

Post by Gareth » Mon Sep 21, 2020 21:01

I agree. North America is similar.

The thing is, they're not classed as road signs in this country and so local authorities pretty much have free reign, with somewhat mixed results.

I also like the blade signs used in North America and some parts of Australia that are attached to the signal mast. Our aversion to mast arm signals makes this a less straightforward option here, however.

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Re: Australian road markings

Post by Peter Freeman » Sun Dec 27, 2020 05:34

Continuing my roundabout versus signals theme, here is an item from an imminent road upgrade local to me. One of the intersections that is currently a 2-lane 4-arm roundabout will be replaced by this signalised crossroads -

NW-Cranbourne Rd ... Thompsons Rd layout.jpg

It's a standard layout for busy D2 or D3 suburban main roads, speed limited variously at 60, 70 or 80 km/h. The diagonal dimension across the central paved area is only about 50m, which is less than the island diameter of a medium-sized UK roundabout. Traffic capacity is high, which is important in this rapidly-growing suburban location.

Widening and signalising the roundabout would probably be the UK solution. However, >2 lanes and signalisation are both rare for roundabouts in AU, having been tried but abandoned. One of the roads here is a fairly major non-freeway in outer Melbourne, but the intersecting road is quite ordinary. FYI, a link to the project page is -
https://roadprojects.vic.gov.au/project ... ad-upgrade

Despite the high rate of roundabout replacements such as this, we still 'do roundabouts'. One interesting current project just outside Melbourne's urban boundary is a link road between our M1 and M420 freeways. As the so-called M420 approaches Melbourne it passes through a small town and an outer suburb before merging with M1. Upgrades there are impossible. The plan therefore is to divert M420 to join M1 farther out, by upgrading a very minor road that happens to be in the right place. It will, like the currently sub-standard M420, ultimately be full motorway, but initially it's being duplicated with only roundabout intersections. Here are the layouts of two of them -

C422 roundabouts.jpg

I think the geometries might shock UK-based Sabristi! Such curvy approaches have become the norm in AU - for speed-reduction/safety reasons of course. The project has a web page at -
https://roadprojects.vic.gov.au/project ... ad-upgrade
Last edited by Peter Freeman on Mon Dec 28, 2020 10:33, edited 1 time in total.

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Re: Australian road markings

Post by Truvelo » Sun Dec 27, 2020 21:24

Those curvy roundabout approaches don't appear to be as nasty as ours when I placed them against some of ours. Those curves start some way before the roundabout so it gives a nice line into the roundabout unlike ours.
How would you like your grade separations, Sir?
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Re: Australian road markings

Post by traffic-light-man » Mon Dec 28, 2020 11:04

A couple of UK roundabout to junction conversions that spring to mind are this one in Warrington, which seems to be a good deal by all accounts, handling the traffic better than the previous far-to-small signalised roundabout (although I don't see much of Warrington at peak times, to be fair).

This is the other one in St Helens, which isn't on satellite view yet. If you ignore the collision scene, you'll notice that signs that have been erected telling drivers how to turn right at a crossroads and pedestrians/cyclists how to use a toucan crossing, so it obviously hasn't been quite as straight forward as it should be. While I think the theory of changing the roundabout to signals is sound, I'm not sure the results have been all that great from a safety point. The old lump of earth in the middle of a 70mph dual carriageway (admittedly, not without its vehicle strikes) has been replaced by a nice wide straight bit of tarmac, with signals and a short 40mph limit - I'm sure you can make a conclusion about the outcome :roll:

On thing they've both undoubtedly done is improve the NMU facilities at the junctions, keeping the crossing points more towards the desire lines and adding controlled crossing points where they were absent previously.

Completely unrelated to the point of a conversion, one thing they do both happen to employ (Warrington and St Helens) is the use of full-greens on the left turns that require a give way, presumably to re-enforce the give way line.
Simon :driving:

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Re: Australian road markings

Post by Peter Freeman » Mon Dec 28, 2020 12:58

traffic-light-man wrote:
Mon Dec 28, 2020 11:04
A couple of UK roundabout to junction conversions that spring to mind are this one in Warrington, ...
That's a neat job, on a smallish scale. UK examples are often notable for the greater degree of channelization, eg. pedestrian refuges separating the right turn lane from straight-on lanes. It provides more safe places for pedestrians, and shorter walk distances for old/disabled/slow walkers. The penalty is a fussy and less obvious layout, and less efficient usage of the available space.
This is the other one in St Helens, ... you'll notice that signs have been erected telling drivers how to turn right at a crossroads and pedestrians/cyclists how to use a toucan crossing, so it obviously hasn't been quite as straight forward as it should be.
I don't see the signs - where? I do see the on-road dashed line to guide opposing right-turners, which is sufficient there but is not as useful as AU's more elaborate and extensive lining style.
While I think the theory of changing the roundabout to signals is sound, I'm not sure the results have been all that great from a safety point.
Yes the safety aspect is interesting. I'm slightly conflicted. Roundabouts do avoid the possibility of high-speed T-bone collisions - IF they are well-designed, small, low-speed, and used sensibly.
I've recently noticed, browsing google earth, a significant number of roundabout-to-cross-road conversions now appearing in the UK. There are a couple on Nottingham ring road, which I used to know quite well. So I'm encouraged that the rotary obsession is weakening.
...and a short 40mph limit ...
That's a larger example, on on important NSL limited-access road, and I think a reduced speed limit is essential at such an intersection. Limits higher than 80 km/h would rarely be found on signalized urban roads in AU - most that I've posted about in this thread would be 60. Speed limits are strictly enforced here, and our drivers, a surprisingly compliant bunch, generally abide by them!

... Completely unrelated to the point of a conversion, one thing they do both happen to employ (Warrington and St Helens) is the use of full-greens on the left turns that require a give way, presumably to re-enforce the give way line.
I find this strange. 'Give Way' means give way - why does it require reinforcement? It's inefficient usage of available time and space if these signals can be red when the road being entered is actually clear.
Last edited by Peter Freeman on Tue Dec 29, 2020 04:32, edited 1 time in total.

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Re: Australian road markings

Post by Rambo » Mon Dec 28, 2020 13:01

traffic-light-man wrote:
Mon Dec 28, 2020 11:04
Completely unrelated to the point of a conversion, one thing they do both happen to employ (Warrington and St Helens) is the use of full-greens on the left turns that require a give way, presumably to re-enforce the give way line.
Are they not just for the pedestrian crossing? I'm familiar with the junction but not the signaling set up..

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Re: Australian road markings

Post by traffic-light-man » Mon Dec 28, 2020 14:17

Peter Freeman wrote:
Mon Dec 28, 2020 12:58
I don't see the signs - where? I do see the on-road dashed line to guide opposing right-turners, which is sufficient there but is not as useful as AU's more elaborate and extensive lining style.
They're the red ones (for drivers) and blue ones (for NMUs) just visible here.

The right turns on the 'cross' road don't have dedicated right turn signalling in this case.
Peter Freeman wrote:
Mon Dec 28, 2020 12:58
...and a short 40mph limit ...
That's a larger example, on on important NSL road, and I think a reduced speed limit is essential at such an intersection. Limits higher than 80 km/h would rarely be found on signalized urban roads in AU - most that I've posted about in this thread would be 60. Speed limits are strictly enforced here, and our drivers, a surprisingly compliant bunch, generally abide by them!
I should say, I'm not particularly against the 40mph, it makes sense IMO, given the circumstances. Unfortunately, I think this one needed 'speed-on-green' combined red light/speed cameras from the outset to at least make an attempt at enforcement. Though we do generally have a problem with speeding, I would say, so I'd have expected speed limit contraventions and plenty of amber gambling from day one.
Peter Freeman wrote:
Mon Dec 28, 2020 12:58
I find this strange. 'Give Way' means give way - why does it require reinforcement? It's inefficient usage of available time and space if these signals can be red when the road being entered is actually clear.
In most scenarios, the left turn would be signalled with a green arrow. A green arrow in the UK generally indicates an un-conflicted movement (there are exceptions, mainly installed under older guidance - or lack thereof), so there's the potential for drivers to disregard the follow-up give way line.

In Ireland, for instance, it's usually replaced with a flashing amber arrow. I believe one Australian response would be to omit the green aspect altogether (similar is permitted in The Netherlands and Germany, to the best of my knowledge), which isn't allowed in the UK.
Rambo wrote:
Mon Dec 28, 2020 13:01
traffic-light-man wrote:
Mon Dec 28, 2020 11:04
Completely unrelated to the point of a conversion, one thing they do both happen to employ (Warrington and St Helens) is the use of full-greens on the left turns that require a give way, presumably to re-enforce the give way line.
Are they not just for the pedestrian crossing? I'm familiar with the junction but not the signaling set up..
As far as I'm aware, at both junctions, the left turns are red if the the traffic from the right has a signalled right-of-way, but green if there a) isn't a conflict, or b) the traffic from the right is from the opposing right turners who are gap-accepting (if that makes sense) which is where the give way comes in to play.

There are definitely some around that are essentially pedestrian crossings, remaining green throughout the cycle unless there's a pedestrian demand. This is one site that springs to mind.
Simon :driving:

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Re: Australian road markings

Post by Peter Freeman » Tue Dec 29, 2020 03:58

traffic-light-man wrote:
Mon Dec 28, 2020 14:17
Peter Freeman wrote:
Mon Dec 28, 2020 12:58
I find this strange. 'Give Way' means give way - why does it require reinforcement? It's inefficient usage of available time and space if these signals can be red when the road being entered is actually clear.
In most scenarios, the left turn would be signalled with a green arrow. A green arrow in the UK generally indicates an un-conflicted movement (there are exceptions, mainly installed under older guidance - or lack thereof), so there's the potential for drivers to disregard the follow-up give way line.
Ah, I understand the point you were making now: the possibility that a driver would assume the green signal over-rules the subsequent give-way line, or he might not notice that line. Especially if that green was an arrow. By the way, here in AU too a green arrow indicates a movement that's unconflicted by either vehicles or pedestrians.
In Ireland, for instance, it's usually replaced with a flashing amber arrow. I believe one Australian response would be to omit the green aspect altogether (similar is permitted in The Netherlands and Germany, to the best of my knowledge), which isn't allowed in the UK.
Yes, omission of the green aspect occurs, quite rarely, in special circumstances. It's always accompanied by a prominent red sign worded "stop here on red signal". I found this sign rather amusing when I first encountered it and before understanding the reason for it.
traffic-light-man wrote:
Mon Dec 28, 2020 14:17
Rambo wrote:
Mon Dec 28, 2020 13:01
traffic-light-man wrote:
Mon Dec 28, 2020 11:04
Completely unrelated to the point of a conversion, one thing they do both happen to employ (Warrington and St Helens) is the use of full-greens on the left turns that require a give way, presumably to re-enforce the give way line.
Are they not just for the pedestrian crossing? I'm familiar with the junction but not the signaling set up..
As far as I'm aware, at both junctions, the left turns are red if the the traffic from the right has a signalled right-of-way, but green if there a) isn't a conflict, or b) the traffic from the right is from the opposing right turners who are gap-accepting (if that makes sense) which is where the give way comes in to play.
In AU we deal with left turn slips differently, using one out of these two scenarios:

1. Single lane (the most common) left turn slips usually have simply a zebra crossing, placed quite early along the slip, followed by a give-way line at the new road entry. There are no signals. This scenario is not allowed where the slip has >1 lane.

2. Multi-lane slips, and some single-lane ones, have a three-aspect signal placed immediately before a pedestrian crossing (not zebra), which is itself quite far along the slip. While it may respond to a pedestrian push-button, this signal is synchronised with the main signals, and so vehicles proceeding over the crossing when the signal is green encounter no other line, either give-way or stop, when emerging onto the new road. I think the green is round, not an arrow - I can't quite remember - I'll take notice next time I'm out! But what it is permitting is quite clear.

At this location you can see both scenarios (zebra and signalised pedestrian crossings) -
https://www.google.com.au/maps/place/Fe ... 45.2331758

(A third, rare, scenario is the one with green aspect omitted. It's a minor variation of scenario 2, with a give-way line following the pedestrian crossing - like your UK examples.)
Last edited by Peter Freeman on Thu Dec 31, 2020 00:26, edited 1 time in total.

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Re: Australian road markings

Post by M19 » Wed Dec 30, 2020 20:21

Truvelo wrote:
Sun Dec 27, 2020 21:24
Those curvy roundabout approaches don't appear to be as nasty as ours when I placed them against some of ours. Those curves start some way before the roundabout so it gives a nice line into the roundabout unlike ours.
It’s the line onto the roundabout that really matters, in guiding people intuitively into the correct circulating lane. UK practice points the left approaching lane towards the right / inner circulating lane of the roundabout, so anyone using the right approaching lane (which is aimed towards the central island) is bound to be cut up by the driver on the left drifting into the right lane.

Classic entry path overlap - we’re brilliant at that sort of thing!
M19

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Re: Australian road markings

Post by Peter Freeman » Fri Jan 15, 2021 01:07

Just a curiosity: a recent minor upgrade and re-line of an existing layout produced this unusual 3-lane elongated clover-loop. It feeds northbound traffic from very busy Hoddle Street onto the M3 Eastern Freeway outbound from the city.

hoddle street loop_3086.jpg

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Re: Australian road markings

Post by Peter Freeman » Thu Feb 11, 2021 09:04

An under-construction motorway project in S-E Melbourne is the Mordialloc Freeway. That's a PR name - really it's just a 7km northern extension to almost complete the existing M11 Freeway (there's a few km still to be added at the southern end too). It includes (offline at Thames Promenade) a roundabout-to-crossroad conversion - standard practise now.

It's not a major project for Melbourne - I show it here simply for a detailed view of the pragmatic and under-stated design and marking of its intersections. Rather unusually, it doesn't appear to have our usual degree of future-proofing, nor does it have smart-tech or ramp metering. However, it has, I think, a distinctive AU 'look' - clearly not a UK road -
https://roadprojects.vic.gov.au/__data/ ... 5x3346.jpg

The existing M11 to its south stretches for 53km, mostly as expandable D2M. This new northern piece will be D2M and will end at a signalised T-intersection with the 20km-long Dingley Bypass. You would have expected a GSJ here, but no, because the Dingley Bypass is currently a D3 with signalised intersections (that are future-proofed for grade separation). There is no doubt the whole Dingley Bypass, including the M11 junction, will be GSJ'd eventually, but that at-grade style of major road does its job well at present.

Here's a project website for those interested -
https://roadprojects.vic.gov.au/project ... %20Freeway
Last edited by Peter Freeman on Fri Apr 30, 2021 14:26, edited 2 times in total.

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Re: Australian road markings

Post by Peter Freeman » Wed Apr 14, 2021 13:21

Continuing the discussion, in this more appropriate forum, of how to alleviate merging problems between closely-spaced motorway interchanges. Earlier discussion here - viewtopic.php?f=1&t=39793&p=1171227&hil ... e#p1171227

A good example is currently under construction on Melbourne's M80 ring road. A 4km length from Sydney Road to Edgars Road, covering three junctions 16-17-18 is experiencing congestion at peak times. AADT is over 175,000. Junction 17, the middle one, where the M31 merges into M80 both eastwards and westwards, is a 3-level directional T. J16 and J18 are diamonds. The ring road's original build, almost 20 years ago, was D3M, with merging facilitated by single auxiliary lanes each way, making D4M between junctions.

The new form will have ramp braiding between junctions 17 and 18. There is insufficient reservation to braid between 16 and 17, so an improved auxiliary lane layout will provide relief for that length. Ramp metering and M2M connector metering will be added, and an existing cable-stayed footbridge will be significantly modified. Construction space is constrained at points, so the through-carriageways will remain D3M in essence, but the works will expand the width up to 14 parallel lanes at maximum.

The scheme will work. It's adding adequate extra width, and importantly it doesn't have a multi-lane drop following a merge (one of the problems at UK M25 J14A/15).

Location on Google maps - https://www.google.com.au/maps/@-37.688 ... 859632,14z
Project page - https://roadprojects.vic.gov.au/projects/m80-upgrade
Project video 1 - https://www.youtube.com/watch?v=_ucMyUeNucE
Project video 2 - https://www.youtube.com/watch?v=k-gmJC18uzU
This video (several years old now) covers earlier M80 upgrades - https://www.youtube.com/watch?v=jTCd7yE_Xiw

Many M80 driving videos are available on youtube, etc - just search.

(edited 15-04-2021 to correct junction numbers)
Last edited by Peter Freeman on Thu Apr 15, 2021 01:29, edited 1 time in total.

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Re: Australian road markings

Post by jackal » Wed Apr 14, 2021 16:35

Certainly they need to remove the weaving between J17 and J18, though technically braiding is not required westbound as they could just run the onramp from the diamond round the bottom of the directional T.

Taking things a step further, where you have a pair of three-arm interchanges coming from opposite sides, you can achieve a braiding quality (i.e. no weaving) solution without any additional bridges, e.g.:

M27 M275 - Copy.jpg
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Re: Australian road markings

Post by Peter Freeman » Thu Apr 15, 2021 02:09

jackal wrote:
Wed Apr 14, 2021 16:35
Certainly they need to remove the weaving between J17 and J18, though technically braiding is not required westbound as they could just run the onramp from the diamond round the bottom of the directional T.
Yes, you're right; and, on the face of it, a more elegant and economic design. I assume it was considered. The reasons for non-adoption might have included -

1. A bit tight on space, though do-able
2. Interference with the cycle and walking paths (which run the whole M80 length, as with all recent Mel motorways)
3. Landscape and wildlife preservation (a small creek wends its way under J17)
4. Lack of symmetry with eastbound
5. Since traffic entering westbound at J18 will most likely continue on M80 past J16, whereas significant traffic from M31 would be seeking to exit at J16, placing J18 traffic left of J17 traffic would induce more weaving westbound between 17 and 16, exactly where there is no space to braid.

BTW, I've edited my post (and your quote of it above) to get the junction numbers correct. The official numbers are 4 higher than my rough guess, which is rather intriguing as I know of only two extra junctions to (possibly) be inserted.

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Re: Australian road markings

Post by Peter Freeman » Thu Apr 15, 2021 03:13

jackal wrote:
Wed Apr 14, 2021 16:35
Taking things a step further, where you have a pair of three-arm interchanges coming from opposite sides, you can achieve a braiding quality (i.e. no weaving) solution without any additional bridges, e.g.:
I suppose two adjacent motorway T-junctions are quite rare. I'd never noticed the one you raise. Two such interchanges, one facing north and the other south, are almost equivalent to a simple four-way cross, but, in this case, with certain movements omitted. At least some of the movements are on unlikely desire-lines, or are provided via nearby roads.

Do you think your suggested modifications should be implemented? I think at least your north-side one should be: it's so easy, and would relieve the A27. The one on the south side is perhaps not as practical since property acquisition would be required to alleviate a sharp left turn.

In both cases, btw, why separate the extra carriageways as early as you show? An extra lane on the left would be ok for most of the distance, as there is no need for further lane changing before the ultimate diverge. Or delay those diverges.

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Re: Australian road markings

Post by jackal » Thu Apr 15, 2021 11:33

Yes, I agree there are reasons why braiding would be used even where not strictly required, usually due to site constraints. There are several such examples in the UK, e.g.:

https://www.google.co.uk/maps/@52.915041,-1.4192761,16z
https://www.google.co.uk/maps/@52.8510101,-1.296309,16z
https://www.google.co.uk/maps/@51.47242 ... 060548,16z
Peter Freeman wrote:
Thu Apr 15, 2021 03:13
jackal wrote:
Wed Apr 14, 2021 16:35
Taking things a step further, where you have a pair of three-arm interchanges coming from opposite sides, you can achieve a braiding quality (i.e. no weaving) solution without any additional bridges, e.g.:
I suppose two adjacent motorway T-junctions are quite rare. I'd never noticed the one you raise. Two such interchanges, one facing north and the other south, are almost equivalent to a simple four-way cross, but, in this case, with certain movements omitted. At least some of the movements are on unlikely desire-lines, or are provided via nearby roads.

Do you think your suggested modifications should be implemented? I think at least your north-side one should be: it's so easy, and would relieve the A27. The one on the south side is perhaps not as practical since property acquisition would be required to alleviate a sharp left turn.

In both cases, btw, why separate the extra carriageways as early as you show? An extra lane on the left would be ok for most of the distance, as there is no need for further lane changing before the ultimate diverge. Or delay those diverges.
Yes, two closely spaced trumpets or directional Ts with the sliproads arranged as suggested are effectively a single four-way freeflow interchange with some offside entries and exits.

I can't think of any other examples in the UK.

A small bonus of doing the south side is that the stupid false roundabout on Port Way would be removed! But yes, it is a bit more awkward, and probably a building or two would have to be CPOed.

My modifications might be worthwhile to relieve the next junction along, which is pretty busy: https://www.google.co.uk/maps/@50.83746 ... a=!3m1!1e3 There's a lot of traffic from Paulsgrove, Portchester, and Port Solent that would prefer to access the M27 east at J12 but can't.

The new carriageways are so long because they need to diverge before the M27 offslips merge in (e.g. here eastbound) to avoid weaving. For most of their length you could even just widen the existing outercarriageways and separate flows with a barrier.

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Re: Australian road markings

Post by Peter Freeman » Tue Jun 15, 2021 14:53


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