Cannon Street / Moorgate tunnel?
 

If you hollowed out
the existing station and put in a downward-sloping track at a gradient of
1:30 (generally considered the practical maximum, i think), you could drop
But if you did that, you wouldn't have Cannon Street Station, meaning
that the Commuters all pile off the trains at whatever the next
station is - presumably Bank, which would be a disaster in terms of
how busy that station is already.

You might need to demolish No 1 Poultry, but it's a horrible building anyway.
Its not such a problem - the bottom 2 floors worth of basement are
isolated from the rest of the building with a concrete slab in between
- they did that so that archaeologists could get down there while they
were building the building above them. But, if you were heading in
that direction, you'd run straight into the Waterloo & City line
platforms, travelator, or the passenger tunnel between the Waterloo &
City platforms and the Central Line.

Don't ask me about how it all fits in with the Bank station complex.
Didn't someone say they thought that was plausible?
It's only really possible if you rebuild the waterloo and city line
platform entrances so that they take a different route; the travelator
and the interchange tunnel effectively block the through-route - the
only way to avoid this is to go below this level, but then you would
need a very steep slope indeed. You can't get through on the right
hand side of the northern line either, because that's where the
Central line platforms and escalator are.

When DLR extensions have been suggested in the past it is usually
mentioned that the Bank of England vaults are in the way too!
The vaults thing is a red herring when it comes to the NCL, though - there
have been serious proposals from the time it opened up to the 1960s to
extend it southward, and none of those had any problem with vaults.
(from the north) I'd assume it would be fine until you actually reach
Bank station - at that point, if you turn right, you hit the (former)
Midland Bank HQ (now some other bank's important building) vaults,
unless you make it a 45 degree turn. The alternative is to pass
through the slight gap between the central line and the ticket hall,
over the northern line, and then turn right. You can't really head
straight on, because there are loads of vaults around there. The DLR
platforms are to the west of the Northern line ones, rather than
directly below, presumably to help avoid undermining them, or the
buildings above - anything any higher would thus need to be to the
east, which basically means you end up heading more towards Monument,
not Cannon street, and there are quite a few listed churches in that
direction, as well as office vaults, that you wouldn't want to
interfere with.

Cannon Street / Moorgate tunnel?
 

You would need to have flat platforms under Walbrook, to replace Cannon
Street Station.
But if you did that, you'd have to avoid the Walbrook river on top of
you, as well as building foundations either side - you'd make it quite
awkward for the platform exits..

Cannon Street / Moorgate tunnel?
 

On Tue, 9 Oct 2007, John Rowland wrote:

Tom Anderson wrote:

Cannon Street bridge is 7.1 metres above the high water level of the
Thames [1], perhaps less at the ends. The rail deck will be a little
above that - not more than 9 metres, and probably less. It's about 260
metres from the point where the bridge makes landfall to Cannon Street
itself, where the space occupied by the station ends (ish). If you
hollowed out the existing station and put in a downward-sloping track
at a gradient of 1:30 (generally considered the practical maximum, i
think), you could drop 8.5 metres in that distance, leaving you at
about the level of the river. You need about four metres over the top
of the track for the train (six if you want OHLE, which we don't). If
Cannon Street is four metres or more above the level of the river, this
idea is just about plausible - at least this far!

In terms of getting to Moorgate, you're then alright, as you have about
650 metres to run, in which space you can dive another 20 metres, which
i think is enough.

You would need to have flat platforms under Walbrook, to replace Cannon
Street Station.

Either there or further north. If the station was part of the Bank
complex, you might need to add another exit somewhere.

tom

--
It is a laborious madness, and an impoverishing one, the madness of
composing vast books. -- Jorge Luis Borges

Cannon Street / Moorgate tunnel?
 

On Tue, 9 Oct 2007, lonelytraveller wrote:

If you hollowed out the existing station and put in a downward-sloping
track at a gradient of 1:30 (generally considered the practical
maximum, i think), you could drop

But if you did that, you wouldn't have Cannon Street Station, meaning
that the Commuters all pile off the trains at whatever the next station
is - presumably Bank, which would be a disaster in terms of how busy
that station is already.

You'd add more exits and passageways when you added the platforms.

You might need to demolish No 1 Poultry, but it's a horrible building anyway.

Its not such a problem - the bottom 2 floors worth of basement are
isolated from the rest of the building with a concrete slab in between -
they did that so that archaeologists could get down there while they
were building the building above them.

Ah, interesting.

But, if you were heading in that direction, you'd run straight into the
Waterloo & City line platforms, travelator, or the passenger tunnel
between the Waterloo & City platforms and the Central Line.

Yes, you'd have to get deep enough to pass under those. Getting past the
District line is going to be interesting too.

When DLR extensions have been suggested in the past it is usually
mentioned that the Bank of England vaults are in the way too!

The vaults thing is a red herring when it comes to the NCL, though -
there have been serious proposals from the time it opened up to the
1960s to extend it southward, and none of those had any problem with
vaults.

(from the north) I'd assume it would be fine until you actually reach
Bank station - at that point, if you turn right, you hit the (former)
Midland Bank HQ (now some other bank's important building) vaults,
unless you make it a 45 degree turn. The alternative is to pass through
the slight gap between the central line and the ticket hall, over the
northern line, and then turn right. You can't really head straight on,
because there are loads of vaults around there. The DLR platforms are to
the west of the Northern line ones, rather than directly below,
presumably to help avoid undermining them, or the buildings above -
anything any higher would thus need to be to the east, which basically
means you end up heading more towards Monument, not Cannon street, and
there are quite a few listed churches in that direction, as well as
office vaults, that you wouldn't want to interfere with.

I believe the plan for extensions of the line beyond Bank has always been
to make it really deep, so it's below any of this stuff.

tom

--
It is a laborious madness, and an impoverishing one, the madness of
composing vast books. -- Jorge Luis Borges

Cannon Street / Moorgate tunnel?
 

On Oct 8, 9:54 pm, Abigail Brady wrote:
I was pondering a map the other day, and I noted quite how close
Moorgate and Cannon Street are. I guess the city widened lines to
Moorgate are a lost cause due to the planned work at Farringdon, but I
wondered whether it has ever been suggested to extend the Northern
City Line south of Moorgate and link up with the line at Cannon
Street, making Cannon Street into a through station. This would
allow, say, the extension of Northern City Line services to London
Bridge and points onward (possibly as part of the Thameslink network?)

Has this ever been suggested? Are they any especial difficulties
apart from the sheer cost of tunnelling in EC2. (Bank of England
vaults?, I can also imagine the gradient being a problem)?

In these days of terrorist threats and flooding from global warming
etc. does the Governor of the Bank of England need to go down to the
vaults every day to count the reserves? Why not move the reserves out
of London to say Skelmersdale or Pontefract thereby freeing up via
routes for London's commuters - by unkinking (or should that be
dekinking the Central Line) or allowing the Drain to be developed as a
cheaper Chelsea Hackney variant.

Cannon Street / Moorgate tunnel?
 

Speaking of Cannon Street, does anyone know exactly what the point of
the current refurbishment is? The ticket office area was refurbished
only a few years ago, and it seems pretty stupid to have shut down the
M&S and all the other retail units when the station was working
perfectly well as it was (nowhere near as crowded or cramped as London
Bridge and Charing Cross).

I think (as I've said on this group before) that it would be good if
they could somehow integrate Cannon Street better into the Bank/
Monument complex. You could have only one District Line station
(saving on staff costs), get better interchange with the Northern &
Central lines from Cannon Street main line, and call the whole thing
"City of London".

Patrick

Cannon Street / Moorgate tunnel?
 

On 10 Oct, 14:28, wrote:
Speaking of Cannon Street, does anyone know exactly what the point of
the current refurbishment is? The ticket office area was refurbished
only a few years ago, and it seems pretty stupid to have shut down the
M&S and all the other retail units when the station was working
perfectly well as it was (nowhere near as crowded or cramped as London
Bridge and Charing Cross).

I think (as I've said on this group before) that it would be good if
they could somehow integrate Cannon Street better into the Bank/
Monument complex. You could have only one District Line station
(saving on staff costs), get better interchange with the Northern &
Central lines from Cannon Street main line, and call the whole thing
"City of London".


It is bizarre the way that the interchange opportunities are currently
discouraged. If I was going from the southeast to, say, Oxford
Street, I'd always go Cannon Street and Central Line, but people are
encouraged to take a dog's leg, which involves a walk from Charing
Cross to Trafalgar Sqare (a similar distance to Cannon Street to Bank)
just because the stations now have the same name.

Cannon Street / Moorgate tunnel?
 

On 10 Oct, 14:58, MIG wrote:
I think (as I've said on this group before) that it would be good if
they could somehow integrate Cannon Street better into the Bank/
Monument complex. You could have only one District Line station
(saving on staff costs), get better interchange with the Northern &
Central lines from Cannon Street main line, and call the whole thing
"City of London".

It is bizarre the way that the interchange opportunities are currently
discouraged. If I was going from the southeast to, say, Oxford
Street, I'd always go Cannon Street and Central Line, but people are
encouraged to take a dog's leg, which involves a walk from Charing
Cross to Trafalgar Sqare (a similar distance to Cannon Street to Bank)
just because the stations now have the same name.

I've always assumed this was because Cannon Street is overwhelmed in
the peak and frequently shut off-peak, whereas Charing Cross is busy
most of the time (reflecting their City vs West End status) - it makes
more sense to direct interchange passengers to somewhere which can
cope with them and where they can go whenever trains are running.

--
John Band
john at johnband dot org
www.johnband.org

Cannon Street / Moorgate tunnel?
 

On 10 Oct, 15:06, John B wrote:
On 10 Oct, 14:58, MIG wrote:

I think (as I've said on this group before) that it would be good if
they could somehow integrate Cannon Street better into the Bank/
Monument complex. You could have only one District Line station
(saving on staff costs), get better interchange with the Northern &
Central lines from Cannon Street main line, and call the whole thing
"City of London".

It is bizarre the way that the interchange opportunities are currently
discouraged. If I was going from the southeast to, say, Oxford
Street, I'd always go Cannon Street and Central Line, but people are
encouraged to take a dog's leg, which involves a walk from Charing
Cross to Trafalgar Sqare (a similar distance to Cannon Street to Bank)
just because the stations now have the same name.

I've always assumed this was because Cannon Street is overwhelmed in
the peak and frequently shut off-peak, whereas Charing Cross is busy
most of the time (reflecting their City vs West End status) - it makes
more sense to direct interchange passengers to somewhere which can
cope with them and where they can go whenever trains are running.


That could be self-fulfilling. Cannon Street is closed Sundays and
late evenings it's true, but direct Central Line access to the whole
of Oxford Street suits a lot of daytime activities.

Cannon Street / Moorgate tunnel?
 

On 10 Oct, 06:10, Tom Anderson wrote:
I believe the plan for extensions of the line beyond Bank has always been
to make it really deep, so it's below any of this stuff.
And how does it get below the northern line in the short distance to
travel, when it starts by being above it, without it having to invade
bank vaults on either side?