On Mon, 21 Jan 2008, MIG wrote:

On Jan 21, 5:08*pm, Tom Anderson wrote:
On Sun, 20 Jan 2008, MIG wrote:
New stations and better interchanges on existing lines could provide a
lot of new person-routes, both north and south of the Thames, at much
less cost than new lines.

I think the original suggestion was about capacity, not routes. Building
more stations on existing lines can't increase capacity.

There are probably cheaper options than extending the Bakerloo, though.

I can't work out a formula, but it seems to me that if people could
travel more directly to where they wanted to go, spending less time on
the transport networks and travelling a shorter distance, it actually
would increase capacity. Interchanges could make that possible.

To a point. If people are making a journey using lines A, B and C, and you
add an interchange between A and C, it relieves B. It doesn't relieve A or
C, though, and if those are at capacity, it doesn't relieve the
bottleneck. It depends on the details of the network, i suppose.

I think you alluded to platforms on the South London line at Loughborough
Junction (interchanging with the Holborn aka Thameslink line) and Brixton
(interchanging with the Chatham main line). Would those add capacity? I'll
assume that people can come from Batterclapstock, ie on the SLL west of
Brixton, from Peckham, ie along the SLL west of Loughborough Junction,
from the southern part of the Chatham, or the southern part of the
Thameslink route, and want to go to one of Victoria, Blackfriars etc or
London Bridge. Looking at the possible combinations:

Batterclapstock - Victoria: no, wrong way
Batterclapstock - Blackfriars: no, take a radial line into town + change
Batterclapstock - London Bridge: no, direct train already
Peckham - Victoria: no, direct train already
Peckham - Blackfriars: no, go via London Bridge / Cannon Street (?)
Peckham - London Bridge: no, wrong way
Chatham - Victoria: no, direct train already
Chatham - Blackfriars: no, change at Herne Hill
Chatham - London Bridge: maybe
Thameslink - Victoria: no, change at Herne Hill
Thameslink - Blackfriars: no, direct train already
Thameslink - London Bridge: no, change at Elephant or Blackfriars

The only journey that gets improved is Chatham - London Bridge: if you're
south of Penge, you can get a direct train or a good change (at Shortlands
or Penge). If you're north of there, you either backtrack to Penge, or do
a double change via Herne and Tulse Hills, both of which are a bit
awkward. Being able to change at Brixton onto an SLL train would make life
easier, even though the SLL route to London Bridge is a bit roundabout.
This would take people off the Tulse Hill or New Cross Gate lines into
London Bridge, and put them on the SLL. Possibly a minor win, i'm not
sure.

To sum up, i think building those platforms would be a good idea, to add
flexibility and resiliency to the network, and to serve local users
better, but i don't think they're going to deliver extra capacity.

tom

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