A417 Missing Link campaign!

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Berk
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Re: A417 Missing Link campaign!

Post by Berk »

I’ll tell you what’s steep too, Kennford Hill, heading into south Devon on the A38. I found I slowed down to 50, despite dropping a gear.

The last time earlier this summer, the berk ahead insisted on only doing 60 (he was in lane 3), so I couldn’t even give it a good run up and see if I could hold my speed. :x
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Re: A417 Missing Link campaign!

Post by jackal »

Vierwielen wrote: Thu Oct 03, 2019 18:17
roadtester wrote: Mon Sep 30, 2019 19:53 Does anyone know what the maximum gradient is on the new scheme? The existing road is quite steep.
The recommended maximum gradient for euro-routes (ie roads with a "E" number) is 8% on roads designed for 80 km/h, decreasing to 4% on roads designed for 120 km/h traffic.
TD 9/93 gives 'desirable max grade' as

3% motorway
4% AP DC
6% AP SC

It is acknowledged that 'in hilly terrain steeper gradients will frequently be required'. 4% is regarded as an 'Absolute Maximum' for motorway, while for AP anything more than 8% is considered a departure.
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Re: A417 Missing Link campaign!

Post by Berk »

How steep are Kennford Hill, or East Ilsley??
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Re: A417 Missing Link campaign!

Post by roadtester »

FTAOD, I’m not particularly complaining about the gradient at the A417 - I think the proposals are easily the best solution given the expense of the alternative of tunnelling, which IIRC would still have involved quite a gradient anyway. In fact, I’d be in favour of more compromises of this sort to get high quality routes done - there are lots of Continental examples of motorways that are steeper and twistier than we are used to in the U.K. and they generally seem to work OK.

Modern vehicles are probably going to be able to cope with seven per cent fairly easily - whether that’s climbing on the way up without slowing to a crawl, or handling the down slope from a braking point of view.

But it’s interesting to reflect on whether such a long sustained steep gradient on an HQDC would have been entertained in the past given the far more punily powered/braked cars and trucks we had then.
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Re: A417 Missing Link campaign!

Post by A9NWIL »

Berk wrote: Thu Oct 03, 2019 23:44 I’ll tell you what’s steep too, Kennford Hill, heading into south Devon on the A38. I found I slowed down to 50, despite dropping a gear.

The last time earlier this summer, the berk ahead insisted on only doing 60 (he was in lane 3), so I couldn’t even give it a good run up and see if I could hold my speed. :x
Its a real shame its not legal to push said people along! If it was it would be so much fun!
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Berk
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Re: A417 Missing Link campaign!

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I didn’t really want an insurance claim. Or I would’ve. :twisted:
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Re: A417 Missing Link campaign!

Post by A9NWIL »

Berk wrote: Sat Oct 05, 2019 23:12 I didn’t really want an insurance claim. Or I would’ve. :twisted:
No I dont either, Im just saying if you could with no repercussions just carefully connect with the slow vehicle in front and speed them up then it would be nice. I wouldnt want to damage the vehicle in front!
Unfortunately if anyone was to try this the person driving the vehicle in front would likely put their breaks on too! So in any case its never going to work.
Anyone that slow should do the decent thing and pull over letting the other people overtake anyway.
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Re: A417 Missing Link campaign!

Post by Graham »

fras wrote: Sat Sep 28, 2019 22:19 Except the Air Balloon disappears. I don't come this way all that often, but it has been fairly regular over the past 15 years, and believe me, there are no places on this route where you can pop in for a meal and a rest.
Speaking as a Gloucestershire resident, I won't miss the Air Balloon if it does disappear as part of these works. Not that there is anything wrong with it - far from it - but this part of the world is absolutely teeming with characterful pubs. I far prefer the Golden Heart (just a couple of miles away, also on the A417), and there is another pub (the Highwayman) also directly on the main road. The Highwayman has suffered in the last 20 years (since the building of the dual carriageway from Cricklade to Cowley), but it will be able to take up the slack if the Air Balloon closes. And there are plenty of excellent places a mile or two off the main road - eg the Royal George in Birdlip, the Green Dragon in Cockleford and the Seven Springs at the A435/A436 junction. There is/was also a pub on the LAR past the Centurion Garage - I can't remember the name of it and I think it has now closed down (another casualty of the building of the dual carriageway).
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Re: A417 Missing Link campaign!

Post by Bryn666 »

Crawler lane design leaves a lot to be desired in this country...
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Re: A417 Missing Link campaign!

Post by Vierwielen »

Robert Kilcoyne wrote: Thu Oct 03, 2019 18:42
Vierwielen wrote: Thu Oct 03, 2019 18:17
roadtester wrote: Mon Sep 30, 2019 19:53 Does anyone know what the maximum gradient is on the new scheme? The existing road is quite steep.
The recommended maximum gradient for euro-routes (ie roads with a "E" number) is 8% on roads designed for 80 km/h, decreasing to 4% on roads designed for 120 km/h traffic.
Slightly off topic, but I would have thought that the gradients on the M62 between Junctions 21 and 22 eastbound and between Junctions 25 and 24 westbound would have exceeded 4%; they would surely be closer to 8% in places.
I checked the J21 to J22 stretch on teh M62 using Goofgle Earth - the steepest gradient that I could find was about 4%. The steepest stretch that I found was a 3.32 km stretch where the road climbed from 197 metres to 329 metres giving a gradient of 3.97%.
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Re: A417 Missing Link campaign!

Post by SJobson »

I went to the consultation at Witcombe Village Hall on Saturday. Had an interesting chat to a couple of the people running things. The Golden Heart will be somewhat isolated; the access to it will be almost solely off the Cowley junction on the new dual carriageway (also serving a couple of single track lanes). I think this is an opportunity to reinstate Ermin St from Birdlip to the Golden Heart; the issue of rat-running shouldn't arise because the new road will of course avert any need to rat-run. Doubt it'll happen despite the old road being substantively still there, and the Land Registry doesn't indicate any of it has been sold off.

Not convinced about the A436's new preferred route (to head west down the A40 first you need to turn acutely left at the existing Air Balloon roundabout, drive half a mile east, uphill, alongside the A417, then turn 180 degrees via two small roundabouts and an underpass to use the tightly coiled sliproad onto the westbound A417. That strikes me as both less safe and more of an impediment to traffic flow than the current arrangement. The A436 is a trunk route and de facto southern bypass for Cheltenham, so it's not as if that movement should be treated in this way.
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Re: A417 Missing Link campaign!

Post by A9NWIL »

SJobson wrote: Wed Oct 09, 2019 13:55 I went to the consultation at Witcombe Village Hall on Saturday. Had an interesting chat to a couple of the people running things. The Golden Heart will be somewhat isolated; the access to it will be almost solely off the Cowley junction on the new dual carriageway (also serving a couple of single track lanes). I think this is an opportunity to reinstate Ermin St from Birdlip to the Golden Heart; the issue of rat-running shouldn't arise because the new road will of course avert any need to rat-run. Doubt it'll happen despite the old road being substantively still there, and the Land Registry doesn't indicate any of it has been sold off.

Not convinced about the A436's new preferred route (to head west down the A40 first you need to turn acutely left at the existing Air Balloon roundabout, drive half a mile east, uphill, alongside the A417, then turn 180 degrees via two small roundabouts and an underpass to use the tightly coiled sliproad onto the westbound A417. That strikes me as both less safe and more of an impediment to traffic flow than the current arrangement. The A436 is a trunk route and de facto southern bypass for Cheltenham, so it's not as if that movement should be treated in this way.
They should have had a big roundabout and proper slip roads for the A436. I can see why it diverts along the A417 for a while the cutting would be too deep earlier on.
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Re: A417 Missing Link campaign!

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SJobson wrote: Wed Oct 09, 2019 13:55 I went to the consultation at Witcombe Village Hall on Saturday. Had an interesting chat to a couple of the people running things. The Golden Heart will be somewhat isolated; the access to it will be almost solely off the Cowley junction on the new dual carriageway (also serving a couple of single track lanes). I think this is an opportunity to reinstate Ermin St from Birdlip to the Golden Heart; the issue of rat-running shouldn't arise because the new road will of course avert any need to rat-run. Doubt it'll happen despite the old road being substantively still there, and the Land Registry doesn't indicate any of it has been sold off.

Not convinced about the A436's new preferred route (to head west down the A40 first you need to turn acutely left at the existing Air Balloon roundabout, drive half a mile east, uphill, alongside the A417, then turn 180 degrees via two small roundabouts and an underpass to use the tightly coiled sliproad onto the westbound A417. That strikes me as both less safe and more of an impediment to traffic flow than the current arrangement. The A436 is a trunk route and de facto southern bypass for Cheltenham, so it's not as if that movement should be treated in this way.
The A436 is not a trunk route - nor, more infamously, is the adjoining A40. But I agree that the A436 is important enough to get a better connection, if that is possible.
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Re: A417 Missing Link campaign!

Post by SJobson »

jackal wrote: Thu Oct 10, 2019 12:59 The A436 is not a trunk route - nor, more infamously, is the adjoining A40. But I agree that the A436 is important enough to get a better connection, if that is possible.
Thanks for the correction - it's a primary route, not trunk of course. Since I haven't yet submitted my response to the consultation I have the opportunity to amend it :D
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Re: A417 Missing Link campaign!

Post by RichardEvans67 »

I'd just like to add a comment about crawler lanes.

I noticed that Crawler lanes tend to end as soon as the hill ends. Surely a heavy vehicle that was slow up the hill would take time to pick up speed again once at the top of the hill. So it would still be going slow when the crawler lane ends, and so would still disrupt the traffic flow. So I think surely a crawler lane would be much more effective if it carried on for a short distance after the top of the hill, to give heavy vehicles a chance to pick up speed again.
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Re: A417 Missing Link campaign!

Post by Johnathan404 »

RichardEvans67 wrote: Wed Oct 16, 2019 11:01 I noticed that Crawler lanes tend to end as soon as the hill ends. Surely a heavy vehicle that was slow up the hill would take time to pick up speed again once at the top of the hill. So it would still be going slow when the crawler lane ends, and so would still disrupt the traffic flow. So I think surely a crawler lane would be much more effective if it carried on for a short distance after the top of the hill, to give heavy vehicles a chance to pick up speed again.
Also some people will change their driving behaviour when they can see that a lane is closing, which will have an additional impact on the traffic flow at the top of the hill. Almost all UK climbing lanes, especially the new ones, end too soon and it makes the facility less effective.
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Re: A417 Missing Link campaign!

Post by jackal »

This crawler lane extends to the next GSJ along. Presumably there is much less of a gradient there - otherwise vertical alignment on the slip roads would be impossible.
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Re: A417 Missing Link campaign!

Post by Owain »

Graham wrote: Sun Oct 06, 2019 23:20
fras wrote: Sat Sep 28, 2019 22:19 Except the Air Balloon disappears. I don't come this way all that often, but it has been fairly regular over the past 15 years, and believe me, there are no places on this route where you can pop in for a meal and a rest.
Speaking as a Gloucestershire resident, I won't miss the Air Balloon if it does disappear as part of these works. Not that there is anything wrong with it - far from it - but this part of the world is absolutely teeming with characterful pubs. I far prefer the Golden Heart (just a couple of miles away, also on the A417), and there is another pub (the Highwayman) also directly on the main road. The Highwayman has suffered in the last 20 years (since the building of the dual carriageway from Cricklade to Cowley), but it will be able to take up the slack if the Air Balloon closes. And there are plenty of excellent places a mile or two off the main road - eg the Royal George in Birdlip, the Green Dragon in Cockleford and the Seven Springs at the A435/A436 junction. There is/was also a pub on the LAR past the Centurion Garage - I can't remember the name of it and I think it has now closed down (another casualty of the building of the dual carriageway).
I'm originally from Gloucestershire, but I've never heard of any of these pubs except the Air Balloon! I guess that reflects how the road affects the perceptions of passers-by. I'll bear these tips in mind though...
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Re: A417 Missing Link campaign!

Post by roadtester »

I drove the A55 from Holyhead today and was reminded that Rhuallt Hill is another example of a steepish modern HQDC:

https://www.google.com/maps/@53.2629028 ... 312!8i6656

Not sure if its's as steep as what's proposed at the A417 though.

Another steepish section is further down the A417/A419 corridor at Blunsdon:

https://www.google.com/maps/@51.6116602 ... 384!8i8192

Both of these have crawler lanes.

Any others?
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Re: A417 Missing Link campaign!

Post by owen b »

roadtester wrote: Thu Oct 24, 2019 23:03 I drove the A55 from Holyhead today and was reminded that Rhuallt Hill is another example of a steepish modern HQDC:

https://www.google.com/maps/@53.2629028 ... 312!8i6656

Not sure if its's as steep as what's proposed at the A417 though.

Another steepish section is further down the A417/A419 corridor at Blunsdon:

https://www.google.com/maps/@51.6116602 ... 384!8i8192

Both of these have crawler lanes.

Any others?
The A9 southbound away from Inverness rises from under 50m to over 200m altitude in about 3km. So that's an average of 5% or so over an extended distance, probably a little steeper in places I expect.
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