Should the JLE have been a separate line?

[Deleted]

Following on from my comments on the crowding on the Jubile on another thread, this leads me to ask whether it would have been a better idea for the extension to have been a completely separate line (called, say, "the Millenium Line" perhaps?) running from Westminster to Stratford - but not connected to the original Jubilee?

It would have avoided the negative effects (crowding, delays etc) that the opening of the extension had on the original Jubilee line - which went overnight from a quiet, lightly-loaded line that was a pleasure to travel on to a rather hellishly crowded (and often delayed) service.

This would also have avoided the early scrapping of the 1983 stock. I know a few people didn't think too highly of the 83s, but I really do think it was an appaling waste of a stock that was still relatively new (and still a darn sight better than the 1992ts, imo).

What do others here think?

[Chris M]

Well, doing as you suggest and terminating at Westminster would have removed a very useful cross-London route. Travelling from Paddington to Canary Wharf would mean a long interchange at Waterloo rather than cross-platform at Baker Street, similary the cross platform at Finchley Road for Canary Wharf passengers from the northern reaches of the Met.

If it hadn't connected with the existing Jubilee Line it would have made more sense to run north of Westminster to Kings Cross (perhaps via Piccailly Circus and Tottenham Court Road) to relieve the Victoria Line through Central London (maybe also continue to do this further north) and provide a direct Waterloo - Kings Cross route. This would have required significantly more tunnelling though.

[upfast]

Had the extension been opened with the moving block signalling then the service would I think have been better. Instead old kit off the Central line was put in, just in time to open for a New Years party at a large tent in south east London.

Was the west end of the line originally going to always remain signalled from Baker Street though or was it going to all go to Neasden? I don't think that lever frames can do moing block!

[Deleted]

The Jubilee Line Extension is notorious for focussing on form over function as it has narrow platforms and old fashioned signalling that has never been sufficiently reliable for a 'new' line.

[ruislip]

Aug 16, 2008 17:24:03 GMT @rob said:

The Jubilee Line Extension is notorious for focussing on form over function as it has narrow platforms and old fashioned signalling that has never been sufficiently reliable for a 'new' line.

I suppose that was one way the line wasn't necessarily future-proofed?

[ducatisti]

I've always thought it should have been built to SSL loading gauge.
Given the majority of the northern end of the original line is the old Met anyway. Then at sometime if the will/money had been found the whole thing could be run with SSL trains, which woul give you a bit more capacity

[edwin]

Aug 16, 2008 17:24:03 GMT @rob said:

The Jubilee Line Extension is notorious for focussing on form over function as it has narrow platforms and old fashioned signalling that has never been sufficiently reliable for a 'new' line.

Narrow platforms? Where?

[Deleted]

London Bridge, for example. The signalling is the real problem though, it's a shame that the project had delays and a strict opening deadline as it would have been better to have implemented a modern signalling system.

[Deleted]

I'd say Westminster is another candidate of narrow platforms as it does look narrower than London Bridge?

[Deleted]

Westminster:



It was a problem with the Victoria (that arguably had neither form nor function on the platforms!).

Compared to other platforms on the JLE (Canary Wharf, North Greenwich) they are too small, especially since they are busy interchange stations.

[metman]

Nothing wrong with these platforms! And there are the doors to stop people falling on the tracks!!

[Deleted]

Aug 16, 2008 21:23:40 GMT ducatisti said:

I've always thought it should have been built to SSL loading gauge.
Given the majority of the northern end of the original line is the old Met anyway. Then at sometime if the will/money had been found the whole thing could be run with SSL trains, which woul give you a bit more capacity

Building to SSL loading gauge would have roughly doubled the cost of tunnelling; not to mention the extra cost of enlarging the tunnels from Finchley Road to Charing Cross. And of course while that work was being done, the Jubilee would have been reduced to Stanmore to Finchley Road.

Get real!!

[cetacean]

The cost of the project is all in mobilising the manpower and machinery to make it happen - excavating a bit more soil once they were there would have added a negligible extra cost in the greater scheme of things. It was madness to go to all that effort to build such small tunnels and such short platforms.

[Deleted]

Aug 17, 2008 6:00:06 GMT @cetacean said:

The cost of the project is all in mobilising the manpower and machinery to make it happen - excavating a bit more soil once they were there would have added a negligible extra cost in the greater scheme of things. It was madness to go to all that effort to build such small tunnels and such short platforms.

Nonsense. Excavating the tunnels to SSL dimensions would have roughly doubled the amount of spoil to be removed, with a significant effect on costs.

The reason for the dimensions of tube tunnels and rolling stock is that, whenever the calculations have been done, it has been found that they give the best balance between cost of construction, cost of running, and income from passengers.

[Chris M]

But when were these calculations last done? I'm guessing it was when the original Jubilee Line was being planned, as once the decision to extend a tube line has been taken you're pretty much stuck with that loading gauge.

[cetacean]

Aug 17, 2008 10:24:18 GMT @sydneynick said:

The reason for the dimensions of tube tunnels and rolling stock is that, whenever the calculations have been done, it has been found that they give the best balance between cost of construction, cost of running, and income from passengers.

The designers of every other metro system in the world disagree.

[Deleted]

Personally I would have liked to have seen the Jubilee run through the docks and turn south from Silvertown / City Airport to serve Woolwich and Thamesmead and terminate at Dartford.

The discussion on tunnel sizes has brought up a few good and a few not so good arguments. The idea that you dig a tunnel and make it any size with just a little further effort don't work too well. The poor old guys removing the extra spoil will also have to return with a considerable number more of the tunnel segments. This has a major bearing on the logistics of the tunneling and the fabrication and storage of the segments. The need for more sites along the route will likely to also require extra tunneling shields to ensure that the line is completed to the original timescale.

The thought on the size has been a major factor in the early years of UndergrounD railways and the Met & Dist were only built with the cut & cover method as they could be built relatively quickly as labour was cheap and 200 brickies and 20 million bricks was also relatively cheap. The need to not run under property in those days also meant that relatively sharp curves were introduced which lent to short wheelbase coaching stock. The development of the size of tube tunnels has not been all that straightforward as the original CSLR was reconstructed to the size of the CCE&H tunnels on formation of the Northern line. With the advent of modern tunneling techniques and the removal of the need to not pass under property has allowed the advent of longer curves allowing higher speeds and longer tube cars.

[Chris M]

Aug 17, 2008 11:02:36 GMT @lnwrelectric said:

Personally I would have liked to have seen the Jubilee run through the docks and turn south from Silvertown / City Airport to serve Woolwich and Thamesmead and terminate at Dartford.

Personally I'm glad it didn't, as it would mean the Central Line would be even more crowded between Stratford and Central London (not that that is physically possible on the majority of rush hour trains).

[edwin]

Aug 16, 2008 22:52:39 GMT @rob said:

London Bridge, for example. The signalling is the real problem though, it's a shame that the project had delays and a strict opening deadline as it would have been better to have implemented a modern signalling system.

London Bridge looks fine to me. The reason Canary Wharf, North Greenwich, Canada Water are wider is because they were built by cut-and-cover. London Bridge and Westminster are bored with TBMs and the latter had to be narrow to avoid subsidence to the Houses of Parliament.

[cetacean]

Aug 17, 2008 11:02:36 GMT @lnwrelectric said:

he discussion on tunnel sizes has brought up a few good and a few not so good arguments. The idea that you dig a tunnel and make it any size with just a little further effort don't work too well.

I think you missed my point - even if doubling the tunnel cross section doubles the costs of building the running tunnels, that's still only one item in the project's budget. Most of the other items (enabling works, escalator shafts, ventilation shafts, stations, depots, track, signalling, etc) aren't affected.

I may be wrong on this, but it's my understanding that all these ancilliary items are where the bulk of the project's costs are. Thus building loads of expensive infrastructure around running tunnels built on the cheap was, as I said, madness. Or at least not the best value for money.

[ducatisti]

The biggest costs in a any job like that are generally real-estate-related, not the physical items.
also, the cross-sectional area isn't doubled.
Costs of materials like concrete and so forth are significant, but nothing compared to land, and labour.

The economics are not as you'd think - or Crossrail would be an order of magnitude more expensive with some siginificanlty bigger tunnels

[amershamsi]

Aug 17, 2008 17:26:13 GMT ducatisti said:

The economics are not as you'd think - or Crossrail would be an order of magnitude more expensive with some siginificanlty bigger tunnels

an order of magnitude is ten times bigger - it's not that much, however at 16 billion, it's several times more than what the JLE cost (which was expensive enough anyway).

We can solve this by looking at the itemised bill - both should have 'tunnelling costs'. If Crossrail is 3 times the amount (allow for inflation), then tunnelling cost is very much about volume removed.

[mrfs42]

Knowing what ducatisti does for a living I'd say that he's got a pretty shrewd idea of the economics and where the costs come from.

[Deleted]

Aug 16, 2008 17:24:03 GMT @rob said:

The Jubilee Line Extension is notorious for focussing on form over function

Yes, I've always thought this, too. I remember the irony of all the awards they were getting for pretty JLE stations and remember thinking "yeah - - get back to me when you start winning awards for a reliable JLE train service "

[ducatisti]

So who's gonna break in and steal the Bills of Quantities?

That 3x cost - is that /mile or overall?
Has inlation/prices rises etc been put in (copper for example has gone up by Something Silly)
Strip out all the newly required features (eg DDA requirements, increased security etc

Do we know how much they are factoring for property blight? Crossrail goes through some more expensive areas than the JLE, and IIRC property blight is related to both the value of the building (which will be higher in the city as they are bigger) and commercial value (also higher becuase of rents etc).

there again, they should be going through more predictable underground geography (is it geology when there's not a lot of rock? where does geogrpahy stop and geology start?)

[madonion]

Aug 18, 2008 11:44:44 GMT @tubeflight said:

Yes, I've always thought this, too. I remember the irony of all the awards they were getting for pretty JLE stations and remember thinking "yeah - - get back to me when you start wining awards for a reliable JLE train service "

i didn't realise the JLE had such big issues.

would you (and everyone else) say that these problems will be mostly resolved by ATO or is the problem more fundamental than that?

[Deleted]

ATO will solve some capacity problems to an extent but only if it is more reliable than the current signalling. Crossrail will also help when it is completed.

[Deleted]

Aug 18, 2008 15:56:26 GMT @madonion said:

i didn't realise the JLE had such big issues.

would you (and everyone else) say that these problems will be mostly resolved by ATO or is the problem more fundamental than that?

The JLE has never been right from the start, imo, (who else remembers the total shambles it was when the extension opened? Daily signal failures that mucked up the whole line) and even now is totally inadequate for the high passenger volumes it carries. I'm not sure how much the advent of ATO will help matters unless it enables a service to be run comparable to that on the Victoria line - I:E; a train every 1 -2 minutes.

[Ben]

Are the tunnels on the JLE built to 14' 'enhanced' size, and is this the same as the tunnel size on the victoria line?

[edwin]

Aug 18, 2008 17:50:57 GMT @tubeflight said:

Aug 18, 2008 15:56:26 GMT @madonion said:

i didn't realise the JLE had such big issues.

would you (and everyone else) say that these problems will be mostly resolved by ATO or is the problem more fundamental than that?

The JLE has never been right from the start, imo, (who else remembers the total shambles it was when the extension opened? Daily signal failures that mucked up the whole line) and even now is totally inadequate for the high passenger volumes it carries. I'm not sure how much the advent of ATO will help matters unless it enables a service to be run comparable to that on the Victoria line - I:E; a train every 1 -2 minutes.

The Jubilee line will run to the same frequency of the Victoria line, higher, even. And the Victoria line doesn't run a train every 1 - 2 minutes, last time I heard it's rush hour frequency was 28.5tph, which is a train just over every 2 minutes.