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Upgrading the Chiltern Line

cle

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I suspect it'll be quicker for anybody on Oxford or Birmingham services to get to their ultimate destination by going non-stop to Marylebone than to change twice, especially given that the interchange at OOC is unlikely to be any smoohter than getting into the Underground network.
This is the one part I would challenge - as I recall, the Chiltern bay/s would be on one of the Crossrail island platforms - so it probably would be far easier, especially with OOC starters - than getting down to the Bakerloo at Marylebone (with another change quite likely?) - or walking to Baker St which has more options. It would actually fit quite perfectly, if it ever happened.
 
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Zomboid

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This is the one part I would challenge - as I recall, the Chiltern bay/s would be on one of the Crossrail island platforms - so it probably would be far easier, especially with OOC starters - than getting down to the Bakerloo at Marylebone (with another change quite likely?) - or walking to Baker St which has more options. It would actually fit quite perfectly, if it ever happened.
Is there anything public domain showing that? If the platforms are not connected to the GWML then it seems unlikely that there'd be a flyover/ diveunder just to get the platforms in the middle, they'd just be located to the north/west of the GWML platforms.

Though it should be a pretty simple interchange either way, just up one escalator/lift and down another.

If there is a flyover then that somewhat changes the equation about whether stopping services to Wycombe could/ should switch over to Crossrail.
 

MatthewHutton

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This is the one part I would challenge - as I recall, the Chiltern bay/s would be on one of the Crossrail island platforms - so it probably would be far easier, especially with OOC starters - than getting down to the Bakerloo at Marylebone (with another change quite likely?) - or walking to Baker St which has more options. It would actually fit quite perfectly, if it ever happened.
The problem with Old Oak Common as a Chiltern terminus is that it’s worse for buses, walking, taxis and for some destinations not on the Elizabeth line.

The idea that you run a semi fast service - most likely to Aylesbury or Milton Keynes from Old Oak Common calling at Gerrards Cross, Beaconsfield, High Wycombe, Princes Risborough and Stoke Mandeville Hospital is reasonable however.
 

JamesT

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This is the one part I would challenge - as I recall, the Chiltern bay/s would be on one of the Crossrail island platforms - so it probably would be far easier, especially with OOC starters - than getting down to the Bakerloo at Marylebone (with another change quite likely?) - or walking to Baker St which has more options. It would actually fit quite perfectly, if it ever happened.
The diagram shown at https://en.wikipedia.org/wiki/Old_O...with_existing,_planned_and_proposed_lines.png has the Chiltern connection being from a separate set of platforms to those currently being constructed. I can't find it now, but there was a map showing a bit of land that had been earmarked for the Chiltern station.
 

Mgameing123

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The problem with Old Oak Common as a Chiltern terminus is that it’s worse for buses, walking, taxis and for some destinations not on the Elizabeth line.

The idea that you run a semi fast service - most likely to Aylesbury or Milton Keynes from Old Oak Common calling at Gerrards Cross, Beaconsfield, High Wycombe, Princes Risborough and Stoke Mandeville Hospital is reasonable however.
I mean I'd say there are alot more useful destinations you can get to from Old Oak Common like Canary Wharf or Heathrow Airport.
 

MatthewHutton

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I mean I'd say there are alot more useful destinations you can get to from Old Oak Common like Canary Wharf or Heathrow Airport.
It would be about 5 minutes quicker to get to Canary Wharf, Whitechapel, Liverpool Street, Stratford and Custom House than the status quo. It’s not that much slower to go on the train to Marylebone and taking the Bakerloo from Marylebone to Paddington is pretty painless.

The bigger time saving is to west London and it would be around 15 minutes quicker to get to Heathrow where you have to turn up 2 hours before anyway and the fastest way to get there is still by taxi from most Chiltern line destinations. Maybe Bicester/Banbury it would be faster by rail than a taxi.
 

cle

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The problem with Old Oak Common as a Chiltern terminus is that it’s worse for buses, walking, taxis and for some destinations not on the Elizabeth line.

The idea that you run a semi fast service - most likely to Aylesbury or Milton Keynes from Old Oak Common calling at Gerrards Cross, Beaconsfield, High Wycombe, Princes Risborough and Stoke Mandeville Hospital is reasonable however.
It is undeniably bad for walking or taxis - depending on where you are going of course.

But as someone just said, there will be many other connection options. And beyond Heathrow, there will be the whole GWML network, and possible one/some overground routes in time.

To the other post, I did recall seeing a bay on a very old plan (HS2 documents perhaps) - but much has changed. I accept that keeping it separated, and Crossrail running - means that is actually probably unlikely.
 

MatthewHutton

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But as someone just said, there will be many other connection options. And beyond Heathrow, there will be the whole GWML network, and possible one/some overground routes in time.
Overground is potentially useful. But for e.g West Hampstead the win is small as the in vehicle time is going to be the same as using the Bakerloo/Jubilee and the frequency is significantly lower.

Agree for Richmond/Clapham the win is real and bigger.

And being able to access the great western network is good - but it certainly isn’t a win beyond Haddenham and Thame Parkway as it’d be quicker via Oxford and you’ve got longer trip times and higher fares to go via London. It’s also almost certainly quicker to drive.
 
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cle

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True. Jobs are along the M4 elevated section, at Slough, Reading... some are more useful than others. There is also a lot of demand for Ealing and Hayes now (or from them) - but yes Oxford does give some access to the GW network. I would say that only its fledgling Bristol service would be helpful... it doesn't do West Country or Wales... per your point on driving, the further, the more appeal (eg Devon/Cornwall)

Heathrow is really the big draw, but yes the M25 is very quick.
 

MatthewHutton

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True. Jobs are along the M4 elevated section, at Slough, Reading... some are more useful than others. There is also a lot of demand for Ealing and Hayes now (or from them) - but yes Oxford does give some access to the GW network. I would say that only its fledgling Bristol service would be helpful... it doesn't do West Country or Wales... per your point on driving, the further, the more appeal (eg Devon/Cornwall)

Heathrow is really the big draw, but yes the M25 is very quick.
I do agree that a semi-fast to OOC makes sense as it gives the southern part of the Chiltern line access to HS2 and Heathrow. But a basic simple 2 platform station which can support perhaps 5 carriages is enough for that.

Maybe if it’s easy you have one platform which can take 8 car trains or something for diversions.
 

Zomboid

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Whatever gets built at OOC will surely be able to handle the longest trains Chiltern operate, which I believe is presently 8x23m.
 

Starmill

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Whatever gets built at OOC will surely be able to handle the longest trains Chiltern operate, which I believe is presently 8x23m.
I thought they still had a capability to run 9*24m? Not that it makes any meaningful difference.
 

cle

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Whatever gets built at OOC will surely be able to handle the longest trains Chiltern operate, which I believe is presently 8x23m.
That is fairly respectable... I thought it was more 5-6 cars - even now including Mk5s although I would wager that OOC-Moor St will never happen given HS2 would be a footbridge away. Unsure if even Oxford would although it might be useful for the intermediate stops (esp Bicester Village) - and could be Cowley by that point. 2tph Cowley, 2tph High Wycombe stopper would cover many people off.
 

Zomboid

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I thought they still had a capability to run 9*24m? Not that it makes any meaningful difference.
I don't know about capability, but there is a working from Oxford in the morning which is an 8 car. It has to shunt around the station and leaves from platform 3 due to not fitting in the bay platforms.
 

CR165022

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I don't know about capability, but there is a working from Oxford in the morning which is an 8 car. It has to shunt around the station and leaves from platform 3 due to not fitting in the bay platforms.
9 Cars do happen, mostly as ECS moves, but they have happened in service, however only on the Oxford route. Birmingham is max 8
 

md2016

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I think Old Oak Common will have to happen due to the capacity limits at Marylebone. You have about 12 metres of barriers where all in and out foot traffic needs to go. It’s surely not just a case of adding carriages as populations expand. If there is a significant issue on the GWR, they already have to operate a queueing system.

The layout at Old Oak Common will be key to usage, but I think it will be favourable for most journeys. I doubt it will take longer to change there at peak times than the far platforms at Marylebone
 

mr_jrt

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Is there anything public domain showing that? If the platforms are not connected to the GWML then it seems unlikely that there'd be a flyover/ diveunder just to get the platforms in the middle, they'd just be located to the north/west of the GWML platforms.

Though it should be a pretty simple interchange either way, just up one escalator/lift and down another.

If there is a flyover then that somewhat changes the equation about whether stopping services to Wycombe could/ should switch over to Crossrail.
An older design had the three turnbacks extending up the NNML corridor under a flyover for the up Crossrail line, with two of them intended for linking to the WCML via the Dudding Hill line. The flyover was removed when the link was cancelled.

You can see one of the designs (abet a low-res copy) here:
 

Starmill

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I don't know about capability, but there is a working from Oxford in the morning which is an 8 car. It has to shunt around the station and leaves from platform 3 due to not fitting in the bay platforms.
Yes I think it was pre-pandemic there were occasional 3+3+3 on Bicester North - London etc. Not the norm now of course.
 

cle

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I think Old Oak Common will have to happen due to the capacity limits at Marylebone. You have about 12 metres of barriers where all in and out foot traffic needs to go. It’s surely not just a case of adding carriages as populations expand. If there is a significant issue on the GWR, they already have to operate a queueing system.

The layout at Old Oak Common will be key to usage, but I think it will be favourable for most journeys. I doubt it will take longer to change there at peak times than the far platforms at Marylebone
I would like it to, I think it's interesting... but only when Marylebone is maxed out at pre-pandy tph, and services are all 6-8 cars, can we really justify further investment. The route isn't growing hugely - other than Bicester population growth. Oxford Parkway looks fairly settled now although there is development on that side of town, like Oxford North. The stadium might see more.

The Cowley extension, if funded, might see extra patronage overall to the area, but I doubt it will be materially impact Marylebone (you'd get to OOC quicker via an Oxford fast!)
 

Mgameing123

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I do agree that a semi-fast to OOC makes sense as it gives the southern part of the Chiltern line access to HS2 and Heathrow. But a basic simple 2 platform station which can support perhaps 5 carriages is enough for that.

Maybe if it’s easy you have one platform which can take 8 car trains or something for diversions.
To be fair HS2 isn't a big benefit when it comes to Chiltern. Chiltern is litterally the stopping service version of HS2 between Old Oak Common and Moor Street (Curzon Street).
 

md2016

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To be fair HS2 isn't a big benefit when it comes to Chiltern. Chiltern is litterally the stopping service version of HS2 between Old Oak Common and Moor Street (Curzon Street).

Perhaps not for central Birmingham. You’d probably save 20-30 mins from High Wycombe by using HS2, for more effort and cost. For anything beyond Birmingham or for the airport, it would surely be worth it.
 

SynthD

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It would be about 5 minutes quicker to get to Canary Wharf, Whitechapel, Liverpool Street, Stratford and Custom House than the status quo.
That’s more specific than any prediction I’ve seen before, how was it made?
 

squingo44

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An older design had the three turnbacks extending up the NNML corridor under a flyover for the up Crossrail line, with two of them intended for linking to the WCML via the Dudding Hill line. The flyover was removed when the link was cancelled.

You can see one of the designs (abet a low-res copy) here:
This is what should have been. Not the Dudding Hill or WCML connections, mind you. Adding the flyover so that the turnbacks would be on the NNML
 

mr_jrt

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This is what should have been. Not the Dudding Hill or WCML connections, mind you. Adding the flyover so that the turnbacks would be on the NNML
Hard agree, but I can see how it was an easy thing to cut to reduce costs.

It would be horrendously disruptive, but it could presumably be added at a later date by reconfiguring the southernmost turnback into a through line to permit the other lines to be taken OOU whilst the flyover was constructed.

Can't really see that happening without being part of some major new project on the Chiltern axis, though.

EDIT:
Just found an old post of mine with a link to much better info and diagrams:
 
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BrianW

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Hard agree, but I can see how it was an easy thing to cut to reduce costs.

It would be horrendously disruptive, but it could presumably be added at a later date by reconfiguring the southernmost turnback into a through line to permit the other lines to be taken OOU whilst the flyover was constructed.

Can't really see that happening without being part of some major new project on the Chiltern axis, though.
Chiltern residents have (sadly to my mind) shown themselves to be unwelcoming of 'development' and therefore undeserving of investment. Perhaps if they were to welcome a few thousand new houses ...
 

Bletchleyite

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Chiltern residents have (sadly to my mind) shown themselves to be unwelcoming of 'development' and therefore undeserving of investment. Perhaps if they were to welcome a few thousand new houses ...

This is quite ironic given how the entire premise of "Metroland" was building houses!
 

BrianW

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This is quite ironic given how the entire premise of "Metroland" was building houses!
Some might say 'hypocritical'. To the ramparts. repel invaders, pull up the drawbridge- these are familiar actions of recent incomers. No building on the fields I love to look over, despite the former field on which my home/ castle has been built. And no closure of the church /pub/ post office/shop I last used five years ago, or was it ten ...?
 

Bletchleyite

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Some might say 'hypocritical'. To the ramparts. repel invaders, pull up the drawbridge- these are familiar actions of recent incomers. No building on the fields I love to look over, despite the former field on which my home/ castle has been built. And no closure of the church /pub/ post office/shop I last used five years ago, or was it ten ...?

You get this hypocrisy in Milton Keynes, which is funny as the logical extension of "don't build houses on that field" is "your own house shouldn't have been built". Only those who lived in the New Town area before designation gets to complain really.
 

Mikey C

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The Chilterns are a National Landscape (formerly AONB), hence they are correctly protected from mass development.
 

BrianW

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The Chilterns are a National Landscape (formerly AONB), hence they are correctly protected from mass development.
IIUC, the designation of a National Landscape does not PREVENT development within its boundaries. Further (again IIRC) a Local Planning Authority is not obliged to consult with Natural England. Natural England seeks to 'constrain inappropriate development' in the designated area. The government is entitled, on behalf of the people, to determine priorities.

Although somewhat outside the boundaries, I wonder whether a Burnham Beeches Garden City might have any scope for a Metroland Mayor ??? Groanworthy?
 

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