Tom Anderson wrote:
On Sun, 14 Oct 2007, Mwmbwls wrote:

http://underground-history.co.uk/claphamn.php

Would this route be of any value to us now if it were turned into a
tube line?

Ooh, spooky. I went down to the Imperial War Museum today (the
camouflage exhibition is quite good - not often you get to see the
uniforms of the Red Army and Public Enemy side by side), and on the tube
was thinking about the old Northern line express plans. Thanks for
posting, now i get a chance to relate my ponderings!

Anyway, yes, clearly, the southern side of the Northern line is
extremely busy. Brixtonite isn't quite right to say it's unlikely to get
any relief from any other projects, as one project currently in the pipe
is the resignalling and splitting of the Northern line, which would
increase frequency by 25%. Still, an express route would help even more.

Interesting page from the RSG lads, featuring scans of a 1940s report on
the shelters:

http://www.subbrit.org.uk/rsg/featur...ers/index.html

There's an interesting quote from RTTC, too:

"[The shelters were] placed below existing station tunnels at Clapham
South, Clapham Common, Clapham North, Stockwell, Oval, Goodge Street,
Camden Town, Belsize Park, Chancery Lane and St. Pauls. It may be
assumed that at these points the deep-level express tubes would have no
stations as the diameter was too small."

Which may be overinterpreting - there isn't room for platforms in any of
the existing tunnels, but the project to convert the shelters to a tube
line could have added them. OTOH, the key stations where you'd want
platforms are all ones which didn't get shelters. The only ones you'd
want today that have are Camden Town and Stockwell.

Does anyone know if there was a route plan for the central stretch?
Would it just have slavishly followed the Northern line, or might we
have seen, eg, a Stockwell - Vauxhall - Piccadilly Circus - Goodge
Street sort of alignment?

Anyway, my thoughts we

- Clapham South is a wise choice for the southernmost limit of the
express line, from my experience of peak loadings round there; bring it
up to the level of the main line north of Balham, through a Seven
Sisters type layout (where slow trains reverse in a middle bay) and have
it take over the existing line to the south.

- North of Stockwell, the default is to follow the breadcrumb trail of
deep level shelters along Northern line into town, up to Camden Town and
Belsize Park, and then, er, to wherever the northern limit of
overcrowding on the line is.

- But you have all sorts of other interesting options that involve
linking up with existing tunnels, and which could thus be substantially
cheaper, although they wouldn't add capacity in central London. Like (in
order of decreasing length of new tunnel):

-- Stockwell - Vauxhall - Westminster - Piccadilly Circus - Tottenham
Court Road - whatever the rest of your favourite Chelsea-Hackney route
is. Okay, this doesn't connect to an existing tunnel, but at least it
connects to an existing safeguarding!

-- Stockwell - Vauxhall/Oval - Kennington? - Elephant & Castle - London
Bridge - Bank - Moorgate - connect to GN&CR for Old Street, Essex Road,
Highbury & Islington, Finsbury Park etc. This option would definitely
have made it very easy indeed to get home from the museum.

-- Stockwell - Oval/Vauxhall - Waterloo - connect to Waterloo & City for
Bank. Plonk in a new station at Blackfriars for maximum win. Possibly
rebuild the Bank station at lower altitude, so that the tunnels can
carry on to the East and do something useful out there (while also
getting out of the way of an easy southward extension of the GN&CR, heh
heh heh).

-- Stockwell - Oval/Camberwell or something - Elephant & Castle -
connect to Bakerloo line for points north.

-- Possibly the best idea, actually: Stockwell, Kennington, connect to
the Charing Cross branch of the Northern line, which will be severed
from the existing southern reach of the line by the splitting. Camden
Town-style cleverness at Kennington could even allow trains from both
central branches to run to both of the local and express lines, which
would make everyone happy.

- If passengers from south of Balham aren't enough to fill the trains,
consider extending south of Morden. I think there was once a plan, a
long time ago, to take over or share the railway to Sutton. Another
option would be a smidgen more tunnel and the eating of the railway
branch to Chessington.

Wasn't the Wimbledon - Sutton line built by the railways as a blocking
move to prevent the underground being extended to Sutton?

--
Arthur Figgis Surrey, UK