The Sydney Trains network contains 178 stations. 25 of these stations have all day 10 minute frequencies. This is mostly in the CBD, Eastern Suburbs, Airport Line, and Lower North Shore Line.
Prior to 2013 this high frequency network was even smaller, consisting only of the 9 stations on the T4 Line between Wolli Creek and Bondi Junction. This remains the case on weekends, with the 2013 timetable improvements only applying to weekdays and not weekends.
In addition, the T1 Line between Strathfield and Chatswood does have some 11 minute gaps which have been counted as 10 minute frequencies even though the technically do not meet the strict 10 minute criteria. But stations like Hurstville in the South and Parramatta in the West, serviced by 7 and 9 trains per hour respectively, do have 10 minute frequencies if measured at Central Station; however different stopping patterns prevent them from having evenly spread out 10 minute frequencies outside of the CBD.
This distinction is important; as a rule of thumb passengers generally value waiting time twice as much as their travel time. The result of this is that a passenger would rather spend 25 minutes travelling on a train than 10 minutes waiting for a train followed by 10 minutes on the train. The 10 minute waiting time is worth the same as 20 minutes of actual travel time, therefore the second option feels like a 30 minute journey and so passengers would often opt for the first option of 25 minutes. This is even though the first option involves a longer total journey time.
This high frequency network could hypothetically be expanded by changing the stopping patterns of some trains. This eliminates the need to provide additional services, though may sometimes necessitate additional train revenue service hours. This is not an exhaustive list. For example it leaves out stations like Newtown which could achieve 10 minute frequencies by having all T2 Line trains stop there, rather than just the current 15 minute frequencies resulting from half the T2 Line trains that do stop there.
- T1 trains that stop at Strathfield to also stop at Burwood. There are technically trains every 10 minutes at Burwood, but the T2 trains are so slow that they arrive in the CBD after the T1 trains. So what is needed here is for some more of the 13 T1 Line trains that stop at Strathfield every hour to also stop at Burwood.
- T4 trains that stop at Sydenham/Wolli Creek to also stop at Tempe. The trains that skip Tempe are not timetabled to run any faster than those that stop there, so this could be done without slowing down the timetable.
- T1 and T5 trains between Blacktown and Harris Park to add stops at intermediate stations spaced evenly apart. While the T1 Line has 7 trains per hour passing through this section of the network, there are also 2 trains per hour on the T5 Line, resulting in 9 trains per hour in total. This would not provide 10 minute frequencies into the CBD, but would provide 10 minute frequencies for those getting a train to/from Parramatta or Blacktown.
The Sydney Trains network actually looks a lot better when all day 15 minute frequencies are the benchmark. 113 stations out of 178 (63%) have 15 minute frequencies. This is high enough for turn up and go journeys when only 1 train is required. However, if a transfer is required; such as to another train or between bus and train; then 10 minute frequencies are a much better benchmark for turn up and go services.
Meanwhile, the 10 minute frequency network is set to expand dramatically in 2019 and then 2024 when the 2 stages of the Sydney Metro project are scheduled to begin operation. This new line will also run at 10 minute all day frequencies, and extend these frequencies further out into the outer suburbs of Sydney than is currently the case.