Odd dual carriageway

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Norfolktolancashire
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Odd dual carriageway

Post by Norfolktolancashire »

On my latest sortie into Norfolk I was driving along a rural side road in the middle of nowhere near Wroxham when I came across a "Dual Carriageway Ahead" sign. Thinking it was a mistake I was surprised to find a sort of D2 separated by trees.

Are there other examples of these types of D2 on minor rural roads?

https://www.google.co.uk/maps/@52.75497 ... 312!8i6656
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Chris5156
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Re: Odd dual carriageway

Post by Chris5156 »

That's D1, not D2!

Yes, there's a few - one in Kent and a more famous one in Wales. I think we've had threads about them before, but "S1" is too short a search term for the forum software!
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c2R
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Re: Odd dual carriageway

Post by c2R »

Chris5156 wrote: Thu Sep 12, 2019 21:08 I think we've had threads about them before, but "S1" is too short a search term for the forum software!
Yes, that's definitely one of the big problems with our chosen field of study and the forum software - lots of what we want to search for is two characters - I was trying to search for an A1 NI thread the other day... And that's one of the reasons I try and link wiki talk pages to forum threads, so that I can ever find anything!
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paully
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Re: Odd dual carriageway

Post by paully »

There's also the one on Mull, where the road goes from "dual carriageway" to single track in a couple of miles: https://goo.gl/maps/7VFKgAEZEMvMbPSA8
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Ruperts Trooper
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Re: Odd dual carriageway

Post by Ruperts Trooper »

c2R wrote: Thu Sep 12, 2019 21:29
Chris5156 wrote: Thu Sep 12, 2019 21:08 I think we've had threads about them before, but "S1" is too short a search term for the forum software!
Yes, that's definitely one of the big problems with our chosen field of study and the forum software - lots of what we want to search for is two characters - I was trying to search for an A1 NI thread the other day... And that's one of the reasons I try and link wiki talk pages to forum threads, so that I can ever find anything!
Use Google, eg "sabre-roads A1 NI"
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c2R
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Re: Odd dual carriageway

Post by c2R »

Ruperts Trooper wrote: Thu Sep 12, 2019 22:11
c2R wrote: Thu Sep 12, 2019 21:29
Chris5156 wrote: Thu Sep 12, 2019 21:08 I think we've had threads about them before, but "S1" is too short a search term for the forum software!
Yes, that's definitely one of the big problems with our chosen field of study and the forum software - lots of what we want to search for is two characters - I was trying to search for an A1 NI thread the other day... And that's one of the reasons I try and link wiki talk pages to forum threads, so that I can ever find anything!
Use Google, eg "sabre-roads A1 NI"
Thanks for the tip, I'd not thought of that.
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jervi
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Re: Odd dual carriageway

Post by jervi »

Odd that they decided to have the "Dual carriageway ahead" sign. I believe its primary purpose is to let angry drivers in a rush that there will be an opportunity to overtake ahead soon, rather than risking an overtake now (due to most DCs having more than 1 lane). And not so much that the sign is used and placed out there for the sake of letting drivers know there's a dual carriageway ahead.
For example, a DC ahead sign was removed before the southernmost part of the A24 DC between Findon and Worthing, because the first 1KM of the DC is now a D1 (used to be D2, but now has turning lanes), therefor drivers cannot overtake (at least sensibly).
https://www.google.co.uk/maps/@50.85905 ... 312!8i6656
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jervi
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Re: Odd dual carriageway

Post by jervi »

Just read the TSM, i'm not far wrong.
Chapter 4 - 5.3.2
Further advance warning up to a distance of two miles may also be given by a sign to
diagram 818.1. This sign may be used to encourage drivers to delay overtaking until the dual
carriageway is reached. Distances greater than two miles are not permitted, as this might result
in impatient drivers trying to overtake on an unsuitable length of road.
PhilC
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Re: Odd dual carriageway

Post by PhilC »

Chris5156 wrote: Thu Sep 12, 2019 21:08 I think we've had threads about them before, but "S1" is too short a search term for the forum software!
One of the most recent threads was "Most Insignificant Dual Carriageway?".
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Re: Odd dual carriageway

Post by paully »

jervi wrote: Fri Sep 13, 2019 04:28 Just read the TSM, i'm not far wrong.
Chapter 4 - 5.3.2
Further advance warning up to a distance of two miles may also be given by a sign to
diagram 818.1. This sign may be used to encourage drivers to delay overtaking until the dual
carriageway is reached. Distances greater than two miles are not permitted, as this might result
in impatient drivers trying to overtake on an unsuitable length of road.
I may be wrong, but I'm sure I have seen one with "5 miles ahead", something tells me it could have been on the A1 somewhere around Berwick.
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Re: Odd dual carriageway

Post by Dan Lockton »

When I was a kid I spent hours poring over a collection of OS maps my parents had, and this particular dual carriageway, as marked on the Landranger, fascinated and mystified me immensely*. I imagined maybe it was some kind of test track, or an old runway, or something (as it's near Coltishall), and living hundreds of miles away, never got the chance to see what it was really like. When Google Streetview came about, I think this was one of the first places I ever looked at!

*Another place was the B-roads between Thetford and Watton, disappearing and becoming a danger zone between the early 60s and the 70s, which I now know was the Stanford Training Area, but I imagined was due to some terrible disaster.
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Re: Odd dual carriageway

Post by Micro The Maniac »

Chris5156 wrote: Thu Sep 12, 2019 21:08 That's D1, not D2!
As a total tangent, what is the Sabristi-speak for a D2 that has been hatched down to oblivion? D1 seems inadequate...
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Re: Odd dual carriageway

Post by ais523 »

I don't think there is one, but "D1.5" would be a sensible coinage. (I guess "WD1" would be consistent with other usage, but sounds ridiculous.)
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jervi
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Re: Odd dual carriageway

Post by jervi »

Micro The Maniac wrote: Wed Sep 18, 2019 13:20
Chris5156 wrote: Thu Sep 12, 2019 21:08 That's D1, not D2!
As a total tangent, what is the Sabristi-speak for a D2 that has been hatched down to oblivion? D1 seems inadequate...
Road as described like this one https://www.google.co.uk/maps/@50.86459 ... 312!8i6656
I'd just say D1.
While the road surface may be wide, the actual driveable space is still restricted to one vehicle, although often I don't see overtaking restrictions (either signed or solid white lines) on these types of road, so I wouldn't call it an D1.5
Sure you could call them WD1 though.
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the cheesecake man
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Re: Odd dual carriageway

Post by the cheesecake man »

ais523 wrote: Wed Sep 18, 2019 14:39 (I guess "WD1" would be consistent with other usage, but sounds ridiculous.)
It does. It names me think not of a road layout but of the first of 39 unsuccessful attempts to invent WD40!
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Re: Odd dual carriageway

Post by Chris Bertram »

the cheesecake man wrote: Wed Sep 18, 2019 21:23
ais523 wrote: Wed Sep 18, 2019 14:39 (I guess "WD1" would be consistent with other usage, but sounds ridiculous.)
It does. It names me think not of a road layout but of the first of 39 unsuccessful attempts to invent WD40!
It's the postcode covering central Watford, isn't it?
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the cheesecake man
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Re: Odd dual carriageway

Post by the cheesecake man »

Chris Bertram wrote: Wed Sep 18, 2019 21:37
the cheesecake man wrote: Wed Sep 18, 2019 21:23
ais523 wrote: Wed Sep 18, 2019 14:39 (I guess "WD1" would be consistent with other usage, but sounds ridiculous.)
It does. It names me think not of a road layout but of the first of 39 unsuccessful attempts to invent WD40!
It's the postcode covering central Watford, isn't it?
Nope
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Re: Odd dual carriageway

Post by trickstat »

Chris Bertram wrote: Wed Sep 18, 2019 21:37
the cheesecake man wrote: Wed Sep 18, 2019 21:23
ais523 wrote: Wed Sep 18, 2019 14:39 (I guess "WD1" would be consistent with other usage, but sounds ridiculous.)
It does. It names me think not of a road layout but of the first of 39 unsuccessful attempts to invent WD40!
It's the postcode covering central Watford, isn't it?
It used to be. The WD1 and 2 postcodes were renumbered a few years ago and the town centre is now in WD17!
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Re: Odd dual carriageway

Post by Bryn666 »

It's dual one lane even if the width is more so just stick with D1.
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Re: Odd dual carriageway

Post by Ruperts Trooper »

Most drivers assume (wrongly) that dual carriageways must have 2 lanes, ie D2, but since D3 is used here for 3 lane dual carriageways then D1 is appropriate for single lane dual carriageways.
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