Re: Sydney's Railway Tunnels

[billbolton.REMOVE-To-EMAIL@computer.org (Bill Bolton)]

On Mon, 2 Nov 1998 19:20:52 +0800, "David & Jan Winter"
<winterd@nospam-icenet.com.au> wrote:

>Meanwhile, I'm interested in diagrams of the tunnels at North Sydney (could
>someone post or send me a scan). Somewhere I got the understanding there
>were short header tunnels branching off the running tunnels. Can anyone
>comment?

When the original tunnel construction for the City Railway was done,
additional stub tunnels were cut for planned extensions.  The stubs
were long enough that any further construction on the extension could
be undertaken without impacting the already operational lines.  This
generally meant that the stubs were built just long enough to duck
under/over the initial operational lines.

Similar construction was undertaken in the tunnelling at North Sydney,
to accommodate a future Warringah railway.  There are stubs off the
two central tunnels that lead to platforms 2 and 3.  The stubs
continue more or less along the platform alignment to a point where
there is a "turnout" connection which joins the Up or Down single
track tunnels (as appropriate) which then becomes a double track
tunnels.  Past the turnout connection, the two single Warringah
tunnels curve North up over the double track tunnel to terminate in
blank walls once clear of the double track tunnel. 

Here's a rough ASCII diagram of the layout.


    In Tunnel              |      In Cutting

                           |W
                           |a
                           |l
                           |l 
   \      \                |  
----\------\---------------+-----------------------
     \      \              |      Platform 1 
------\------\-------      | 
       \      \      \     | 
        \      \      \    |      Platform 2
         \       ----------+-----------------------
          \                |
           \               |
            ---------------+-----------------------
                      /    |      Platform 3
                     /     |
---------------------      |
                           |      Platform 4
---------------------------+-----------------------
                           |

The stub off track 2 has tunnel lighting along almost its length, but
I'm not sure whether the stub off track 3 does.

For many years there was a big street map (by Robinson's?) of the
North Sydney area fixed to the tiling at the top of the entrance
stairs, near the bus stops.  This showed the path of the tunnel stubs
quite clearly in relation to the local streets.  As far as I recall
from that map, the tunnels terminate somewhere under the grounds of
"Shore" (Sydney Church of England Grammar School).

Cheers,

Bill


Bill Bolton
Sydney, Australia