A421 dualling to M1

[JammyDodge]

Making the Buckingham Bypass a D2 would be a bit tricky, as there is development on both sides, although I agree that A43 to Finmere and Buckingham East to Bottledump would be relatively simple.

Best option would probably be to build a new alignment to the south, as HE's aim seems to be to make the A421/A428 a continuous HQDC in the very long term
I expect in the future, the A421 will be dueled to the A43 and on to the M40 heading North

[Micro The Maniac]

Best option would probably be to build a new alignment to the south, as HE's aim seems to be to make the A421/A428 a continuous HQDC in the very long term
I expect in the future, the A421 will be dueled to the A43 and on to the M40 heading North

Ah... the not OxCam (not) Expressway?

[Bryn666]

Now the A421 has been done what the area really needs now is M1 J14 being sorted out, this is absolutely pants as a motorway access from an urban area the size of MK.

[A303Chris]

Making the Buckingham Bypass a D2 would be a bit tricky, as there is development on both sides, although I agree that A43 to Finmere and Buckingham East to Bottledump would be relatively simple.

Best option would probably be to build a new alignment to the south, as HE's aim seems to be to make the A421/A428 a continuous HQDC in the very long term
I expect in the future, the A421 will be dueled to the A43 and on to the M40 heading North

Trouble is the A421 west of the M1 is not a HE road and is local authority controlled. Given it runs through 4 authority areas MK, Bucks, Oxon and Northants (the latter three in just 6 miles between Buckingham and the A43), and the middle two were against the expressway, well specifically the NIMBY's and the retired people living in the 50s who are the council members , I can not see much hope.

Also MK is an issue as the existing route has 15 roundabouts and it would need a new route to the south as would Buckingham. The original Buckingham purpose may have been fit for purpose but is now a residential route given the development which has occured both sides of the road.

[SteveA30]

Something which is happening to many bypasses across the country. New rbts for housing estates, changing the road to a local road congested with through traffic. Isn't that what bypasses are supposed to cure? I know some are not called bypasses, as a get out clause but in reality they are because the through traffic transfers to them.

[Chris Bertram]

Something which is happening to many bypasses across the country. New rbts for housing estates, changing the road to a local road congested with through traffic. Isn't that what bypasses are supposed to cure? I know some are not called bypasses, as a get out clause but in reality they are because the through traffic transfers to them.

(cough)Burgess Hill By-pass(cough)

[RichardA35]

Something which is happening to many bypasses across the country. New rbts for housing estates, changing the road to a local road congested with through traffic. Isn't that what bypasses are supposed to cure? I know some are not called bypasses, as a get out clause but in reality they are because the through traffic transfers to them.

To be fair it has been like this for a long time. The detrunking of the 1997 New Deal for Trunk Roads placed long lengths of bypasses in the hands of local governments who did not have the strategic or even regional outlook for these roads to make much sense other than as county or local roads an developers were waiting to pounce once the opportunities were clear. In recent times the political outlook has been a focus on how many jobs or how much new housing a scheme will enable before funding is released for local road improvements. The benefit side of the equation is lower against the same costs if the enabling of housing or jobs is not included a,nd currently, politically less palatable..
The times of relieving day to day town or village centre through traffic congestion or safety schemes requiring bypasses are generally over as these have been built (with perhaps a few notable exceptions).

[c2R]

Making the Buckingham Bypass a D2 would be a bit tricky, as there is development on both sides, although I agree that A43 to Finmere and Buckingham East to Bottledump would be relatively simple.

Best option would probably be to build a new alignment to the south, as HE's aim seems to be to make the A421/A428 a continuous HQDC in the very long term
I expect in the future, the A421 will be dueled to the A43 and on to the M40 heading North

Trouble is the A421 west of the M1 is not a HE road and is local authority controlled. Given it runs through 4 authority areas MK, Bucks, Oxon and Northants (the latter three in just 6 miles between Buckingham and the A43), and the middle two were against the expressway, well specifically the NIMBY's and the retired people living in the 50s who are the council members , I can not see much hope.

Also MK is an issue as the existing route has 15 roundabouts and it would need a new route to the south as would Buckingham. The original Buckingham purpose may have been fit for purpose but is now a residential route given the development which has occured both sides of the road.

The A421 could be widened on-line through Milton Keynes - there's a lot of space to either side of the road, as well as space at the junctions themselves to grade separate. I don't think it would be an ideal solution - but housing appears to be sprawling in an uncontrolled manner to the south without actually having any coordinated road infrastructure being built along with it, Newton Leas being the latest example of this...!

[KeithW]

Making the Buckingham Bypass a D2 would be a bit tricky, as there is development on both sides, although I agree that A43 to Finmere and Buckingham East to Bottledump would be relatively simple.

Best option would probably be to build a new alignment to the south, as HE's aim seems to be to make the A421/A428 a continuous HQDC in the very long term
I expect in the future, the A421 will be dueled to the A43 and on to the M40 heading North

I am not convinced it would be impossible to dual, yes there is development but on the southern side its mostly industrial /retail and the verges are quite wide. It lloks like it was originally S3. This is about the narrowest section.
https://www.google.co.uk/maps/@51.99100 ... 8192?hl=en

[JammyDodge]

The A421 could be widened on-line through Milton Keynes - there's a lot of space to either side of the road, as well as space at the junctions themselves to grade separate. I don't think it would be an ideal solution - but housing appears to be sprawling in an uncontrolled manner to the south without actually having any coordinated road infrastructure being built along with it, Newton Leas being the latest example of this...!

It certainly could be grade separated through MK, with D2 flyovers and D3 in between or D2 with frontage roads (basically D4). This would reasonably require a 50 limit.
The question is, should we be building an expressway through an urban area, rather than building it around, especially when it is possible to build a new HQDC to the East from Bottledump and the M1

[JammyDodge]

Making the Buckingham Bypass a D2 would be a bit tricky, as there is development on both sides, although I agree that A43 to Finmere and Buckingham East to Bottledump would be relatively simple.

Best option would probably be to build a new alignment to the south, as HE's aim seems to be to make the A421/A428 a continuous HQDC in the very long term
I expect in the future, the A421 will be dueled to the A43 and on to the M40 heading North

I am not convinced it would be impossible to dual, yes there is development but on the southern side its mostly industrial /retail and the verges are quite wide. It looks like it was originally S3. This is about the narrowest section.
https://www.google.co.uk/maps/@51.99100 ... 8192?hl=en

I am in agreement that it wouldn't be impossible, but grade separation would be out of the question

[c2R]

It certainly could be grade separated through MK, with D2 flyovers and D3 in between or D2 with frontage roads (basically D4). This would reasonably require a 50 limit.
The question is, should we be building an expressway through an urban area, rather than building it around, especially when it is possible to build a new HQDC to the East from Bottledump and the M1

The other way of looking at it is that it's not *that* urban, and building a new route to the south would likely encourage similar development to spring up around it anyway...

[A320Driver]

I also had a brief look down at the M1 all lane running scheme. To my non-expert cursory eye it looked more or less ready, with lane one (former hard shoulder) coned off.

Sadly some new signs have been erected which state that completion is scheduled for Spring 2023 now, delayed by a year!

[M4 Cardiff]

I guess something like the attached would be buildable, but at almost 18km would not come in cheap and the eastern junction would require a Truvelo Special to avoid it becoming a pinch point worthy of Chris' 'Bad Junctions.

[JammyDodge]

I guess something like the attached would be buildable, but at almost 18km would not come in cheap and the eastern junction would require a Truvelo Special to avoid it becoming a pinch point worthy of Chris' 'Bad Junctions.

Certainly a good alternative to my idea, which is one further out to the east

The junction with the M1 is solvable. Mirror what is on the other side, and make it a half diamond. In future, when it is a problem, convert the interchange into the "classic british" big roundabout with too many lanes, and when that isn't enough, make it even bigger.
Joking aside, the current junction does seem well positioned to become a 3-level stacked roundabout in future, or a more elaborate design emulating J11A on the M5, with modifications