Monday 13 October 2014

Station for Sydney University: Reading Between the Lines

The following was speculated by blogger OzRails:

"I really hope that this means that they are reconsidering their removal of the Inner West line from their plans.  It was originally discarded because of the complexities where the tunnel was to surface at Redfern, well that's not happening and they are considering a path that runs in the exact direction to allow a branch to join the inner west line between Newtown and Stanmore where there is space for the tunnel to meet the existing line to Homebush. So that would see 15 tph for the Bankstown line (confirmed by TNSW) and 15 tph for the inner west line. This would not only provide a much improved service to the inner west but would free up space on the Main South line and a faster journey to the CBD for those trains as they run express from Homebush to just before the CBD other than Strathfield and Burwood. The tunnel for the Inner West SRT line would have the SYD uni station.
...
One may then ask, what happens with the Hurstville branch? It would have to stay as it is right now but if youre looking to convert the ESR to Metro then you use the Hurstville and Revesby branches to feed that line along with the stations from Sydenham to Erskineville. So 15 tph for each branch plus 30 tph for the ESR (extended to supplement the Light Rail). "

This could explain a lot of the discrepancy between the Rail Futures 2012 document and the 2014 SRT documents.  If the above speculation by OzRails is correct, then TfNSW have basically discarded their Rail Futures 2012 plan (to link Hurstville local tracks to the SRT), and have gone back to an earlier plan to connect the Inner West locals to the SRT....  Yet another TfNSW reversal!  (Not that I think plans should be fixed forever and never be reviewed).



Yet it all makes sense and explains why TfNSW are thinking of a Sydney University station on the SRT, and why they no longer show the Hurstville local tracks in their June 2014 SRT documents,  It also explains a bit about their Western line capacity "upgrade package":  TfNSW must have been caught off guard by Mike Baird's acceleration of the SRT plans and are trying to firm up their plans between now and the release of the 2014 State Infrastructure Review, and hence the vague and sketchy description in June 2014 of what their Western line upgrade package actually comprises... basically TfNSW are making up their plan as they go along!  Assuming the above speculation is true, this is the SRT network that TfNSW are right now are looking into (note the local tracks from Homebush are converted to SRT single deck metro, and connected to the rest of the SRT network):


Reading further between the lines, I believe TfNSW are resurrecting the inner west metro conversion plans because they have come to realise their 2012 Future Rail plan does *not* deliver the western line capacity upgrade required (as I previously wrote in this post).  Additionally, they have also come to realise their plans to free up Western express train capacity by redirecting Northern line trains into the city circle as per page 29 of the internal FutureRail capacity investigations (obtained by SMH) is a bad idea (very poor value, at estimated cost of $680 million for just a junction reconfiguration, and also messing up sectorisation).  Why does sectorisation mixed up?  Because the Northern trains need to share track part of the way with Harbour Bridge sector trains to avoid being held up by all stops from Homebush trains, and then after Central station, need to cross over to the City Circle line tracks.

Instead, with this hypothetical "new SRT" plan, the all stops trains from Homebush will be diverted into the SRT line to free up city circle capacity for South line (8tph) and other express trains (12tph).  Which trains will therefore go onto the city circle?  My guess would be 6tph Northern trains (using flying junction at Strathfield) as well as 6tph Richmond trains.  These trains would all run on the middle pair of tracks between Strathfield and CBD before entering the city circle.  The Emu plans/Blue Mountains/St Marys trains then would have exclusive use of the upper pair of tracks between Strathfield and the CBD, before continuing onto the harbour bridge.

So how does this new TfNSW plan compare to my proposal?  Our plans share in common the metro conversion of the Inner West line.  However, my plan uses the Rozelle Railyards to create an extra pair of tracks into the CBD, so it has *four* pairs of Western line tracks entering CBD, whereas the hypothetical "new SRT" plan has only three pairs of Western line tracks.  As a result, Northern line trains will still be constrained to 6tph in "new SRT".  It is possible to give more trains to the Northern line branch, but only by taking away trains from other branches.  This is because with only three track pairs in the "new SRT" plan, after one pair of tracks are used for metro conversion, there are just 2 track pairs left between Strathfield and the CBD, which is a bottleneck on the capacity of the three branch track pairs (Main North, Main South, and Main West) where they converge at Strathfield.  In contrast, with four tracks pairs, metro conversion of one track pair will leave three track pairs, nicely matching the three North/South/West track pairs that converge at Strathfield.

Also, my proposal allows the conversion of the airport and Revesby lines to metro and thus improves airport line & city circle capacity to 30tph (and making better use of Museum/St James which are currently underutilised).  It's unclear how how TfNSW will provide more capacity on the Revesby line, as in their configuration, metro conversion of Revesby & City Circle would require metro conversion of South, North and West suburban tracks as well.  OzRails speculates Revesby and Hurstville might feed into the Eastern Suburbs line, but this will create a lot of empty and wasted capacity on the eastern suburbs stations.  My proposal connects these four tracks in a more balanced way: Inner West + Revesby is one metro sector (linking to City Circle), and Hurstville/Bankstown is in the second metro sector (linking to SRT)

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