Newark Bypass

[c2R]

I actually don't understand the rationale for opting to build to the north in the first place... Other than A1 under the junction, I can't imagine most of the A46 traffic stays on the A46 through the junction; the main routings have to be A46E->A1N; A17->A1N and A1N->A46E and vice versa

[skiddaw05]

Would the southern link road join the A1 at the existing junction at Fernwood? Without improvements here this could become a Winthorpe Mk II by the look of it.

[jackal]

If it's a particular problem to dual the existing bypass, wasn't it considered to take the southern link road, dual it, renumber it as A46, and take the mainline of the A46 with it? The existing single (northern) section could be retained and perhaps renumbered as A617. A couple of slip roads could be built at Winthorpe Roundabout taking the A46 directly on/off the A1. Winthorpe could be retained.

Obviously it's more direct to take the northern route for either the A46 to Lincoln or A1 to Doncaster (the two main onward routes). You'd need two new freeflow junctions, and you'd have to widen the A1 (and beyond three lanes if the rest of it is made three lanes). The final result would still be somewhat suboptimal as you'd be mixing A1 and A46 traffic that has no reason to mix.

This is one instance of the 'rule of the four way interchange'. Basically if you have two high quality routes, it's better to have them cross without conflict at a purpose-built interchange rather than get jumbled together on what is effectively a long weaving section, as for instance is common in France with its proclivity for toll-boothed trumpet interchanges. A more complicated (because it involves more than two routes) British example is the M1/M62/M621 mess.

[jackal]

By the way the scheme has effectively been in the programme since late 2014, for a post-2020 start. Existing thread here:

viewtopic.php?f=1&t=37887&p=925605

[c2R]

Obviously it's more direct to take the northern route for either the A46 to Lincoln or A1 to Doncaster (the two main onward routes). You'd need two new freeflow junctions, and you'd have to widen the A1 (and beyond three lanes if the rest of it is made three lanes). The final result would still be somewhat suboptimal as you'd be mixing A1 and A46 traffic that has no reason to mix.

This is one instance of the 'rule of the four way interchange'. Basically if you have two high quality routes, it's better to have them cross without conflict at a purpose-built interchange rather than get jumbled together on what is effectively a long weaving section, as for instance is common in France with its proclivity for toll-boothed trumpet interchanges. A more complicated (because it involves more than two routes) British example is the M1/M62/M621 mess.

Possibly, but it does depend on the amount of traffic that actually goes A46-A46 - I suspect not a lot...

[Euan]

I actually don't understand the rationale for opting to build to the north in the first place... Other than A1 under the junction, I can't imagine most of the A46 traffic stays on the A46 through the junction; the main routings have to be A46E->A1N; A17->A1N and A1N->A46E and vice versa

It turns out that a road journey from Birmingham and much of the West Midlands to Humberside is slightly quicker going via A42/M1/M18 than via the A46 at Newark, so there probably will not be that much traffic staying on the A46 beyond Newark.

[ForestChav]

The existing bypass is banked up, reasonably close to the town, river, and railway at various points. The embankment would definitely have to be widened to dual it. Whilst that isn't impossible, it would no doubt be costly...

[wrinkly]

The existing bypass is banked up, reasonably close to the town, river, and railway at various points. The embankment would definitely have to be widened to dual it. Whilst that isn't impossible, it would no doubt be costly...

It's also very soft ground, which is why the original A46 bypass was so expensive. It's also a flood plain, requiring flood connector culverts under the road.

[2 Sheds]

Something is about to be done.

https://highwaysengland.co.uk/regions/e ... us=PLANNED

Sounds like cheap and cheerful tinkering around the edges to me. Do any of the professionals on here think these measures will make any worthwhile difference to justify the disruption and cost ?

[TheKeymeister]

Something is about to be done.

https://highwaysengland.co.uk/regions/e ... us=PLANNED

Sounds like cheap and cheerful tinkering around the edges to me. Do any of the professionals on here think these measures will make any worthwhile difference to justify the disruption and cost ?

Looks like next to no improvement but plenty disruption for 7 months, and if they're spending money on drainage and street lighting, probably not much chance of a proper upgrade any time soon either...

A46 Cattle Market, Brownhills and Friendly Farmer roundabouts, Newark
From: January 2019 To: July 2019 Closures
Work: PLANNED
Cost: TBC
Safety improvement works will be carried out on the A46 Cattle Market, Brownhills and Friendly Farmer roundabouts.

A46 Cattle Market roundabout works will include:

widening and realignment of the (B6326) Great North Road arm
A46 Brownhills roundabout works will include:

widening of the A1 northbound exit slip road
re-profiling of the existing embankment to reduce the slope gradient
A46 Friendly Farmer roundabout works will include:

reduction of lanes from 4 to 3 on the A46 approach
re-alignment of the footway on the south east quadrant, which will be changed from a segregated to shared path
We will also introduce full spiral markings to all three roundabouts. This will make it easier for drivers to choose and follow a lane around the roundabout and lead to a reduction in collisions and the disruptions they cause at the junction.

In addition to the above, we will also deliver associated works including resurfacing the roundabouts and immediate approaches, replacing / adding to the High Friction Surfacing, replacing lighting columns / lit signs, updating signage, installing a new drainage system for surface and sub-surface water, renewing footways / cycleways and renewing the landscape within the central islands.

[Hdeng16]

Would it be possible/useful to ‘do a Chiverton Cross’ here and create a new roundabout for the GNR and the A617 to meet, with then a single link to the A46?

Would create a 4 way roundabout rather than 5. No idea whether it would make any difference, but it’s a tough one to get right on the cheap.

[Berk]

I would approach the matter a little differently. It appears that the current bypass made a lot of concessions to not only the terrain, but the sugar factory, northern suburbs, etc.

In other words, very sharply curved. A traffic nightmare, in other words (there almost inevitably have to be roundabouts with that sort of design).

I would try and pull the southern half of the current bypass back a little bit (this could be done by dualling), up to the A617. So yes, you would probably end up with a formation similar to Scotch Corner, where the A6108 is briefly dialled on the run up to it; here that would be the A617, meeting the A46.

I would then build a brand new stretch of A46 bypassing Winthorpe. The A17 could multiplex with that, or just go round on its current course; it can be left as a ‘development road’/local bypass. Plus the A17/A1 link.

It’d be nice if some sort of flyover could be introduced for both halves of the A17, but I imagine it would be extremely tight. You’d also have to shorten the A1/B6166 slip in some way.

[Euan]

There would not be too much of a problem dualling the A46 from the south as far as the A616/A617 roundabout - the road is wide enough at the roundabout itself. However widening would need to commence not too far from the roundabout where the road narrows. The same could be said about the approach along the A46 the other way.

The only serious bend along the Newark Bypass is on the approach to the north end of the B6166 which would make dualling less straightforward than anywhere else on the bypass. The fact that there is a sharp bend would support the idea that the northern half of the bypass could remain S2 even if the southern half were to be dualled - dualling at the bend would be discouraged and if the road leading up to the bend were to be dualled there would be lanes converging along the bend leading to the roundabout. Without a doubt traffic flow would not at all be efficient if that were to happen.

[stu531]

Don't know if I've got this right from what's been said above, but couldn't you take the A46 to the north/west of Winthorpe, so the A46 doesn't meet the A1 at the current junction - but that it follows the railway line towards Lincoln, and a new junction built at the top of the current curve (ie at the top of Alexander Ave)?

That way, traffic at the existing junction wouldn't include Leicester-Lincoln traffic. You could build limited access slips from A46 northbound to A1 northbound and vice versa, without needing to change the A1/A46/A17 junction.

[TheKeymeister]

I'm not a highway engineer by any means, but I reckon as said above, dualling between Farndon and the A46/A617 roundabout doesn't look like too much of a challenge. The section between there and Winthorpe would be a challenge due to whether there's actually space to widen the embankment on the section where the road runs between the railway and the Trent. The whole thing looks like a pain due to the number of river and rail crossings, especially considering the road crosses the rail to then cross back again.

I think you could sort Winthorpe out by doing something like this. Create a new roundabout junction with the A1 to the north/west of the current one. Tie in the A46 to the north and south into this directly, and create a spur from this new roundabout to the current A46/B6166 roundabout, which would retain the existing connection to the B6166, with the existing bridge from there over the A1 tieing in directly with the A17 and removing the 'Friendly Farmer' roundabout. As far as I know, movements between the A17 and the A46 north of that point are pretty limited anyway, with the possible exception of HGV traffic from the business parks close by off the A17, most longer distance traffic would use the A15 at Holdingham to get towards Lincoln and beyond.



It's not exactly a wonderful freeflow creation, but nothing like that is ever going to happen there unfortunately! It straightens the curve out a bit, gives proper slips to the A1 as the current ones regularly result in traffic queuing back onto the mainline A1, moves the junction a touch further away from the A1 Coddington one as they're currently a bit close, removes some conflicts for A46>A1 and A46 through traffic whilst not really adversely affecting A17 and Newark local traffic. The Friendly Farmer pub and the one the other side of the A46 would be lost, but last time I tried to go there the Friendly Farmer was shut down anyway. Replace the two petrol stations with a new one that catches traffic from both directions (possibly off the new A17/B6166 roundabout?) and that should keep everyone reasonably happy. You could of course plug the A17 straight into the new roundabout but I feel that would maybe cause too much traffic on the roundabout itself. You could counteract that by having the A46 on a 3rd level and going over the top but I think that's entering dream land, especially with there being an existing roundabout anyway at Newark Showground which would presumably remain...

[ForestChav]

It's by no means insurmountable but you're underestimating the gradient - the existing bypass is banked up a fair amount due to the flood plain, and so that might be quite difficult.

[ForestChav]

I'd remodel slightly where the A46 diverges from the railway making the bypass carry "straight on" converting the existing A46 from there to the B6166 island into south-west bound slips. The mainline A46 then continues to hug the railway line over the A1 without a junction to the north of Winthorpe, meeting the A1133 at an island where the latter currently diverges from its previous route througb Collingham to meet the A46. The A46 then takes over the last section of A1133 but dualled to the existing roundabout. If necessary, you could make the existing A46/A1133 junction into another set of directional slip roads to the A17/A1, and you could make the A1133/Collingham local access a dumbell. The latter would have more land take and make the showground only accessible from the A17 (since you'd have to sever that, or link it over the A46 into Collingham itself).

[ForestChav]

Would it be possible/useful to ‘do a Chiverton Cross’ here and create a new roundabout for the GNR and the A617 to meet, with then a single link to the A46?

Would create a 4 way roundabout rather than 5. No idea whether it would make any difference, but it’s a tough one to get right on the cheap.

Very little traffic from either the A616 or A617 goes onto anything other than the A46, other than local traffic going into Newark. It'd make no difference.

In fact, nor would taking the A46 traffic off. The A617 and A616 are the links from Mansfield/Southwell and Ollerton to the A1

[Hdeng16]

Yep I get that, and for clarity I was looking at cheap crap options (so those likely to get approved!).

Perhaps aim looking from a selfish POV but the ex-A1 B road was at one point signed as Newark from the southbound A1, and when the the A46 is busy, the queues here can go back well past the sugar factory entrances.

It was more about whether removing an arm from the main A46 roundabout would allow other options there. I hate saying it, but maybe the extra space would allow traffic lights on the roundabout.

The main problem is that it needs an overpass, but has zero chance of getting it.

[KeithW]

The basic problem from the point of view of this long term A1 user is the roundabouts. The fact that the Brownhills and Friendly Farmer roundabouts are both overloaded and far too close to the A1 junction inevitably impacts the A1 as traffic leaving it backs up along the slip roads and onto lane 1 of the A1 - sometimes for over a mile. This in turn leads to extremely nasty rear end impacts and who wants to the car in the HGV sandwich ?. Approaching Newark I am afraid I become a lane 2 hogger as once you are stationary at the end of that queue there is no getting into lane 2.

This reminds me of the Black Cat fiasco to the south and I fear all that will happen is the same process of tinkering which will mean expense and disruption at the end of which the situation will be no better. What has made things worse is the local planners permitting uncontrolled development around the junction which has basically left no free space in which to work and increased traffic loads.

If as has been suggested through traffic on the A46 is relatively light I would think in terms of a spur from the A46 to the west carrying the A46 up to North Muskham on a line close to the old Great North Road. This would require new bridges over the Trent and ECML.

The A17 traffic from the east would use a properly implemented southern bypass and join the A1 to the south thus splitting the through and A1 traffic flows. The existing roundabouts would remain as they are as with 75% of the traffic gone and the crossing traffic much reduced there should be no problem.