Some more specific notes to explain the tables below:
1. Baseline 2014 data: taken from TfNSW Bureau of Travel Statistics train station barrier counts.
2. Forecast 2024 data: projected from 2014 data using historical growth rates 2006-2014.
* NWRL data taken from TfNSW projections and added to North Shore & NWRL 2014-2024 growth rate.
3. AM peak entries: apply to the period 6am to 9:30am.
4. Suburban transfers/exits: see explanatory note after tables.
5. Peak Pax to Capacity Ratio: interpretation is as follows
* ratio ~ 0 to 1: well below capacity even during peak hour (8am-9am)
* ratio ~ 1 to 2: at capacity during peak hour, spare capacity in shoulder periods of AM peak
* ratio ~ 2 to 3: at capacity during peak hour & during shoulder periods of AM peak
* ratio ~ 3+: exceeds capacity even in shoulder periods
Ok, here are my spreadsheet tables for 2014 & 2024. (Future post will cover 2036 & 2049).
Some interesting details discussed below are the following:
1. Sydney Metro already has a hidden "West Metro" branch
2. The critical role of suburban interchange at Strathfield in balancing overall system patronage.
Explanatory Note on Sydney Metro's Hidden "West Metro” Branch
According to page 33 of 2014 NSW State Infrastructure Strategy Update:
"The Western Sydney Rail Upgrade Program will deliver civil and electrical infrastructure on the T1 corridor to enable longer (12 car) Intercity trains to operate and to improve the separation of Intercity and suburban services, increasing capacity west of Strathfield. This is intended to complement the Sydney Rapid Transit project, which is Transport for NSW’s preferred option for addressing constraints between Strathfield and the Sydney CBD. In conjunction with Sydney Rapid Transit, the SRF2 program, as currently costed, has an indicative benefit- cost ratio of 1.6."
It is expected that of the order of 15,000 passengers would be disembarking Western line trains terminating at Central. As per above, these passengers would then be expected to interchange onto Sydney Metro at Central. So effectively, Sydney Metro already has two "branch" lines in the sense it is taking on not just the Bankstown line but also a significant amount of Western line trains from Central onwards. These sorts of numbers also make me question whether 15 trains per hour x 6 car trains are sufficient to handle the amount of Western line interchange required, and if very soon after deployment we could see Sydney Metro frequencies go up to 20+ trains per hour x 8 car trains (the pax:capacity ratio in the table above only reflects the Bankstown "branch".
It is recommended that Sydney Metro (south of Central) not be branched any further. The patronage projections in the previous pages indicate Bankstown line and terminating Western will eventually need the full 30tph capacity of an unbranched Sydney Metro. Adding any further branches will within ten years result in a problem (yet again) of how to “untangle” metro lines that are at capacity.
(February 2016 note: branching Sydney Metro north of Chatswood on the other hand has a strong rationale as it better balances the "south" vs "north" patronage, where south = patronage from Western + Bankstown line commuting into Pitt St/Martin place stations and north = patronage from north of Chatswood commuting into CBD).
Explanation about the critical role of Suburban Transfers (especially at Strathfield)
Note in the first table above that the Inner West & South line's total daily patronage of 126,000 station entries is only approx 10% less than the Western's line 142,000 station entries. (Burwood has been classified in the Inner West line, to reflect probable 2024 timetable & operational plans).Yet the Inner West & South has 30% less current capacity when measured in trains per hour (14 vs 20). As seen in the chart below, considerable numbers of passengers interchange at Strathfield, typically getting off the slower all stations Inner West services and boarding faster express services on the Western line and Northern line.
This interchange at Strathfield actually plays a critical role in balancing the overall rail system function, both at present and into the future. The present reason is because the Inner West tracks are capacity constrained by the “tangling” up with Bankstown trains in the City Circle and as a result are limited to 14 trains per hour (versus the 20 trains per hour achievable on the Western line). By having large numbers of passengers transfer at Strathfield, this frees up capacity on all stations Inner West trains to pick up more passengers at stops east of Strathfield. In contrast, Western and Northern line trains run express into the CBD, and as a result, do not pick up more passengers except at Burwood.
In year 2024, the Inner West line will have dedicated use of the City Circle as Bankstown trains will be taken over by Sydney Metro. This will boost capacity to 20 trains per hour. However, all this capacity is needed simply to meet the projected 2%pa growth in patronage in the 10 years to 2024. As a result, the interchanging of passengers at Strathfield is still needed to free up capacity for stations east of Strathfield. The Year 2024 model assumes therefore that approximately 10,000 passengers will interchange at Strathfield, except a higher proportion will use Northern line trains rather than the Western line. This is because in Year 2024, it is anticipated a majority of Western line trains will terminate at Central and not continue on into the CBD. It is also anticipated in Year 2024, longer (12 car) trains have been introduced on the Western line, boosting it's capacity to 25 trains per hour (when expressed in 8 car train equivalents). The Northern line will also be anticipated to have higher capacity as well due to a greater share of harbour bridge capacity ceded to it by the Western line trains terminating at Central. As a result, both the Western line and Northern line will continue to have some spare capacity to accept the interchanging Inner West line passengers at Strathfield.
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