Bournemouth & Poole road schemes

[Richardf]

Thought for a while that improving or replacing either the A350 or A349 might offer the best solution for a Poole to A31 link, rather than anything closer in as previously planned. Dualing the Wimborne bypass would be necessary as part of this but its needed anyway.

[Truvelo]

Where would the route to the A338 and the Airport have gone? Are we talking following the A3060 Castle Lane route and creating a northern bypass for the conurbation?

That's basically it. West of A348 Ringwood Road is accurate but east of there I only have the route in written form. The placement of the cloverleaf junction is also estimated as I don't know exactly where the north-south and east-west roads cross. I've also drawn it slightly too big

[jackal]

^ Is that exact cloverleaf design (with the semi-direct connector for eb to sb) in the documents or is it also an estimate?

[Peter350]

Where would the route to the A338 and the Airport have gone? Are we talking following the A3060 Castle Lane route and creating a northern bypass for the conurbation?

That's basically it. West of A348 Ringwood Road is accurate but east of there I only have the route in written form. The placement of the cloverleaf junction is also estimated as I don't know exactly where the north-south and east-west roads cross. I've also drawn it slightly too big

Wow looks impressive!

I have a query about the road to the north of the cloverleaf which appears to be a link to the A31 between West Moors and St Leonards: Was this intended to be built instead of the current A338 Bournemouth Spur Road, or would it have co-existed with the latter? Having both exist at once would seem a bit overkill unless there were grandoise plans to expand the Bournemouth/Poole conurbation to rival the car-dependent new towns.

[Richardf]

^ Is that exact cloverleaf design (with the semi-direct connector for eb to sb) in the documents or is it also an estimate?

Bit overkill if it is, it only connects with Parley Lane to the north and local roads to the south!

[Richardf]

Where would the route to the A338 and the Airport have gone? Are we talking following the A3060 Castle Lane route and creating a northern bypass for the conurbation?

That's basically it. West of A348 Ringwood Road is accurate but east of there I only have the route in written form. The placement of the cloverleaf junction is also estimated as I don't know exactly where the north-south and east-west roads cross. I've also drawn it slightly too big

Not sure i like that plan really. I'd be in favour of a decent northern bypass to replace Castle Lane A3060 but that seems way over the top, doesnt connect with all the existing north south roads and doesnt seem to cater for a decent link to the A31? Unless i am missing something?

[Truvelo]

I've done my best to decipher the written text in the report and translate it into a map of the proposed roads. Everything shown would have been a grade separated dual carriageway. All the connections between the major roads would have been trumpets or freeflowing. Two of the routes would have been full blown motorways. I assume if the M27 had been extended through New Forest and the Verderers would have been less vocal back then the M27 could have started at West Parley. This is the junction which would have been a modified cloverleaf. Three other designs were evaluated but they were rejected in favour of the cloverleaf.

https://www.google.com/maps/d/edit?mid= ... sp=sharing

[Richardf]

Truvelo, all I can say is Wow! Knowing the area pretty well part of me is very glad most of it didn't get built as planned, although watered down versions of some of them would be beneficial today!

Which schemes would have been motorways? Does the report say?

[Truvelo]

Which schemes would have been motorways? Does the report say?

West Parley to Picket Post.

[jackal]

Thanks for this Truvelo. I can see why the cloverleaf with semi-direct connector was selected. The stackabout, for instance, has over 20,000 AADT in all four corners. The vast majority of this traffic is turning between the western and southern arms, movements which are not just freeflow but fast and weaving free in the cloverleaf design. While there is weaving on some of the remaining movements they are lightly trafficked.

This would be a good design even today for junctions with a dominant pair of turns. Indeed, the designers of the Black Cat rebuild faced a very similar choice. Sadly we have regressed to the point where a stackabout is now preferred to a freeflow design even at that much busier site, and tens of thousands AADT will be forced through the roundabout.

[Truvelo]

Stackabouts or any other perfectly symmetric junctions only work when there's an even spread of traffic using each arm. Those arms downstream of the main flow onto the roundabout will have trouble joining.

Here's the AADT of the cloverleaf.

[jackal]

Great! With only 900 aadt on the 'middle' loop the weaving is barely even there.

What are the roads numbered/named?

[Truvelo]

The only numbering is routes 1 to 19 which is just for various sections of each road. These are shown in the Google Maps overlay.

[Peter350]

Surely the road bypassing the north of the conurbation would have become the A35? Looking at the map, the line ends where Blackwater interchange is today but I would assume it was intended to continue as far as the Christchurch Bypass.

My guess is that the N-S road through the cloverleaf would have become a diversion of the A31, and the road through Ferndown and Wimborne given an Axxxx number.

[Truvelo]

The report says the route around the north of the conurbation joins the A338 at a trumpet adjacent to Holdenhurst sewage works. The Christchurch Bypass joins the A338 to the north of St Catherines Hill without specifying an actual location. Although it would make sense to have this as one continuous route the presence of a trumpet rules this out. However I agree about giving it the A35 number.

[BOH]

Were there plans for the A338 Wessex Way from the Cooper Dean to the St Pauls roundabout to be D3 at some point? Was driving along this route yesterday and there is a very wide central reserve that could easily fit a 3rd lane each direction.

[Vierwielen]

In might be useful to remember that in the last county reorganisation, the Dorset district councils were replaced by two unitary authorities: Bournemouth, Christchurch and Poole on the one hand and Dorset UA on the other. As a useful approximation, Dorset UA is repsponsible for the A31 (including Ferndown) while BCP is repsonsible for most of the area between the A31 and the sea (apart from Ferndown). As a result, we can expect the various councillors to play silly political games with each other (as happened between Poole and Bournemouth for years).

[Truvelo]

Were there plans for the A338 Wessex Way from the Cooper Dean to the St Pauls roundabout to be D3 at some point? Was driving along this route yesterday and there is a very wide central reserve that could easily fit a 3rd lane each direction.

Yes, the report states it will initially be D2 and widened to D3 later. St Pauls roundabout would be a trumpet, so too would the Cambridge Road roundabout.

Regarding the councils, the former separate Poole and Bournemouth councils is why the 1/2500 plans I have stop at the boundary as I only have the proposals for Poole. I would rather have had Bournemouth as there were more roads and the junctions had a bit more spaghetti.

[John McAdam]

In might be useful to remember that in the last county reorganisation, the Dorset district councils were replaced by two unitary authorities: Bournemouth, Christchurch and Poole on the one hand and Dorset UA on the other. As a useful approximation, Dorset UA is responsible for the A31 (including Ferndown) while BCP is repsonsible for most of the area between the A31 and the sea (apart from Ferndown). [...]

Dorset Council (the UA) is not responsible for the A31 - rather it's Highways England. Ditto the A35 west of Bere Regis, and a short stretch of the A303 in the north of the county.

On the north western edge of the BCP area, there's just a short stretch of the A31 near Oakley that's an HE responsibility.