On Mon, 13 Aug 2007, Mr Thant wrote:

On Aug 12, 11:55 pm, somersetchris somersetchris.
wrote:

The only bottle neck will be Canonbury tunnel.

I meant the ECML diveunder south of Finsbury Park station, which I don't
think could be fixed to be double track very easily (I realise there is
a second track already, but it's pretty heavily used by trains from
Moorgate)

?

Okay, are we now talking about terminating the ELL at Finsbury Park, by
reversing out of a bay platform on what is now the Canonbury reversible
line? If so, yes, you're quite right - you'd need to make that diveunder
three-track, or else you have a single-lead approach that stretches all
the way to the NLL. From the air, there looks like there's enough space to
add a third track; are there pillars or something in the way down there?
Failing that, there are a couple of places you could put in passsing
loops: around Drayton Park, and between the diveunder and the station
(exploiting the existing goods track that joins the down Canonbury from
the main line).

Given that there will still be a single-track bit through the tunnel, how
much difference does this really make?

tom

--
a draw was agreed once the pieces started melting