Tom Anderson wrote:
On Thu, 18 Oct 2007, Colin McKenzie wrote:

A Hammersmith MP writes (in a circular email):

I believe there should be an additional station on the Crossrail
line at Old Oak to interchange with the West London Line. It is
technically possible to build this, but the economic case will
depend on the success of the Overground system.

I agree an extra station would be beneficial, but I think it should
interchange with the North London Line. New platforms could be
built on that line to interchange with Crossrail at one end and
the Central Line at the other end.

This location is known as Acton Wells, incidentally - Acton Wells
Junction is where the Dudden Hill freight branch and the curve from
the GWML join the NLL, where it crosses the Central and the
Paddington - Chiltern line.

Yes, and any station that links to both the GWML/Crossrail and the
Central Line would be in the middle of Acton Wells Junction, a vital
node on the London freight network, which also has links to the WCML and
the WLL. You would have to build a new bridge across the
Central/Chiltern lines and separate the freight traffic, thus making it
more difficult to justify the cost/benefit.

The West London line already interchanges with the Central Line at
Shepherds Bush, so my suggestion would give more new travel
options. What do the assembled experts think?

It's been brought up about a billion times, and i think everyone
likes it from a connectivity point of view, but we have a hard time
justifying it in raw benefit-cost ratio (not that we've done the
maths).
There are potential operating cost savings in it if it meant you
could close North Acton (definitely) and Acton Main Line (possibly).

Acton Main Line is much closer to the centre of Acton than Acton Wells,
so closure of AML would be extremely unpopular. You could only close
North Acton if there was equivalent platform accommodation at Acton
Wells, which looks doubtful.

When the campaign group PROgress Alliance launched a petition* about
this on the PM's site (which attracted just 50 signatures, 1% of their
target), they hijacked a photo of mine without permission to illustrate
the site, their copy of which is at
http://bp1.blogger.com/_plHFyAJszvA/.../DSCN1210w.jpg
The bridge in the photo carries the NLL; the Chiltern line from High
Wycombe is on the left; the Central line is on the right; the GWML is
out of shot to the right.

* http://petitions.pm.gov.uk/StopAtNorthActon/


The top priority, of course, is getting Crossrail built - without
wasting time reconsidering all possible changes to the proposal.

Debatable. Building it wrong now pretty much precludes building it
right any time in the near future. Would you rather have the wrong
line now, or the right line in ten years' time? I think that's a
tough choice.
Incidentally, there was an idea to build a link through the depot
around there to run down to Richmond:

http://www.hounslow.gov.uk/crossrail.pdf

That was the "Corridor 7" proposal to run a relatively low-cost branch
to Hounslow (NOT Richmond) via a link through Old Oak Common depot on to
the NLL, then from South Acton on to the Hounslow Loop using an existing
freight link. It would have made better use of some of the (up to) 14
trains per hour that are planned to reverse at Paddington. It would
have provided a connection between Crossrail and the NLL at Acton
Central.
--
Richard J.
(to e-mail me, swap uk and yon in address)