Sunday, April 10, 2011

The Devil is in the Details

Based on the Werribee-Williamstown-Sydenham spreadsheet that I have earlier compiled, I have focussed on how the tabled changes will affect Altona passengers. By hiding the irrelevant rows (train stations) and columns (train runs) while retaining the connections at Laverton, Newport and North Melbourne, a clear picture has emerged. The results are contained in this processed spreadsheet which I am asking you to download so that you can follow what I am discussing.

I have harnessed the powerful processing power and visualizing capabilities of Excel, and am pretty awed by what I see. The train arrival times are highlighted in blocks of yellow, green and orange, which show how you should connect trains in order to get to your destination. The connection flows are constructed based on the sequential order two connecting trains arrive at the connecting station. You should follow the colour path down each column and to the right when connecting trains. Note that there are jumps in the colour flow to the right due to the way Metro structures the timetable. I have retained the Watergardens and Williamstown stations to indicate whether the connecting trains are Sydenham or Williamstown trains respectively.

My mother from Singapore does not understand English. She tried to remember the train station that we should get off (Westona) by counting the number of train stations from the boarding station. I told her it is futile for her to depend on this method. Sometimes the train stops all stations, sometimes it skips some stations and sometimes it decides not to run on that day or bypass the Altona Loop altogether. Further complicating matters is that trains of different lines may arrive at the same platform in a haphazard order not according to schedule. Sometimes the train goes in a clockwise direction in the City Loop, sometimes in an anti-clockwise direction. Sometimes it goes through the City Loop, sometimes it does not. Sometimes the train starts off from Flinders Street, sometimes from Southern Cross and sometimes from Flagstaff as I have now realized from this timetable. Adding to this confusion is that sometimes the train departs from one platform, sometimes from another and sometimes oscillates between platforms. I recall there were a number of occasions in which large number of stranded commuters were told to move from one platform to another, then back and forth, with the train staff also equally uninformed. I would say that the new timetable laid in front of me looks rather convoluted and is more likely to make things more complex for train passengers. If simplicity is elegance, this is backpedalling.

I will be picking some train stations such as Westona, Melbourne Central, Werribee and Seaholme to illustrate the journey time in the discussions below.

Thanks to Daniel, please note that the computations of the journey time between the Altona Loop and City Loop are based on connecting to Sydenham trains at North Melbourne. The times will be different if you connect to Cragieburn or Upfield trains. The most accurate source of information will be from Metro which should be able to supply all the journey times between the Altona Loop and City Loop stations for the whole day. If someone can request such information from Metro, that will be great so that we do not need to do the computations ourselves.

Whole Day Journey Time

Please refer to the Excel spreadsheet for the computations.

Train JourneyRangeMedian Journey Time
Westona to Melbourne Central29 min to 1h 10 min50 min
Melbourne Central to Westona31 min to 1h 1 min50 min
Werribee to Seaholme28 min to 1h 4 min23 min
Seaholme to Werribee16 min to 39 min30 min


City-bound Services

Chart_Westona_to_MelCentral

There are 6 morning peak Laverton trains (highlighted in yellow in the Excel spreadsheet) stopping all stations to Flinders Street, departing Westona at 6:58, 7:20, 7:42, 8:04, 8:26 and 8:48 am. The journey time between Westona and Melbourne Central ranges from 29 to 36 min during this period.

The first Altona Loop Shuttle arrives Westona at 9:08 am and runs until 4:29 pm. The shuttle services are highlighted in red in the spreadsheet. There is a 7 min waiting time at Newport to connect the city-bound Werribee train. The average time to reach Melbourne Central (based on connecting to a Sydenham train at North Melbourne) is about 50-53 min from 9:08 am to 11.50 am, 1 hour and 3 min from 12:10 pm to 15:50 pm and the last 2 interpeak journey takes 53 and 49 min.

Eight Laverton trains run again from 4:48 pm to 7:29 pm, with the time to reach Melbourne Central ranging from 44 min to 1 hour 10 min.


City to Altona Loop Services

Chart_MelCentral_to_Westona

Eight morning Laverton trains run, with the connecting Sydenham trains departing Melbourne Central at 5:46, 6:00, 6:25, 6:52, 7:12, 7:41, 8:00 and 8:13 am, taking 45 to 58 minutes to reach Westona.

It is surprising that there are 2 more Laverton trains running towards the Altona Loop compared to the city-bound ones, which total 6. Low passenger volumes will help in keeping these trains to schedules. Scheduling a higher frequency of such trains will thus improve the performance of Metro.

Taking the 8:30 am train at Melbourne Central will connect to the Altona Loop Shuttle, arriving Westona an hour later at 9:30 am. The next 2 trains will take 58 & 57 min journey time, followed by 1 hour and 1 min journeys until 2:41 pm, where the journey time drops to 49 min. It is easier if you take the Williamstown Train from Flinders Street or Southern Cross, alight at Newport and wait 6 min to connect the Altona Loop Shuttle.

There are 6 evening Laverton trains to Laverton (compared with 8 Laverton trains running in the reverse direction), with the connecting Sydenham trains departing Melbourne Central at 4:36, 5:09, 5:27, 5:55, 6:03 and 6:18 pm, taking 34 to 54 min to reach Westona. These are followed by trains terminating at Werribee, instead of Laverton.


Werribee to Altona Loop Services

Chart_Werribee_to_Seaholme

I find the connections at Laverton to be somewhat enigmatic. I will explain by using the timetable shown below:

Laverton_Connection

During the morning peak, a Werribee Train arrives at Laverton at exactly the same time (at 7:16, 7:38, 8:00, 8:22 and 8:44 am) as the Laverton Train. There is a shift of 1 min for the next pair of trains (9:25 and 9:26 am).

It is impossible for 2 trains to be at the same platform at exactly the same time. Hence, the 7:16 am Werribee Train and the 7:16 am Laverton Train will have to arrive Laverton on different platforms. Laverton Train Station has 3 platforms. Platform 2 and 3 are on the same island so you can just simply cross from one side to the other side of the island. The recently built Platform 1 serves city-bound trains and is connected to Platform 2 and 3 by an overhead bridge.

If the 7:16 am Werribee Train and the 7:16 am Laverton Train arrives at Platform 2 and 3, transferring from the Werribee Train to the Laverton Train may still be possible (although I doubt this to be frequent) as you can simply walk across the island. Connection will not be possible if one of these trains arrives at Platform 1. However, I do not think the Laverton Train will wait for a Werribee Train just for passengers to make the connection as the delay will have flow-on effects on the subsequent journey. The Laverton Train stops all stations to Flinders Street so any delay at the starting Laverton Station will greatly impact the punctuality at a large number of subsequent stations. Hence, for this reason, I think you will have to board an earlier Werribee Train to make the connection. For example, to reach Seaholme Station at 7:24 am, you will need to board the 6:56 am train at Werribee Station.

During this morning peak period, it will take 28 min to travel from Werribee to Seaholme. However, if you board the 7:04 am Werribee train, the journey will take 1 hour and 4 min, arriving Seaholme at 8:08 am. The situation improves to 23 minutes when the Altona Loop Shuttle is running. The best time to take a train from Werribee to Seaholme is after 6:58 pm, when the journey time is reduced to 18 min. This is because the Altona Loop has returned to the fold of the Werribee service.


Altona Loop to Werribee Services

Chart_Seaholme_to_Werribee

During the morning peak, it takes 27 to 30 min to go from Seaholme to Werribee. The journey time is further increased to 38 min when the Altona Loop Shuttle operates between 9:23 am and 5:01 pm (times departing Seaholme), when there is a waiting time of about 16 min at Laverton to connect the Werribee-bound train. The best time to take a train from the Altona Loop to Werribee will be after 7:25 pm, when the journey time is reduced to 19 min. But how many people will be travelling between these 2 regions at this late hour of the day?

Passengers travelling between Werribee and the Altona Loop are the worst affected. Travel time from Seaholme to Werribee will increase from the current 20-21 min to 38 min (an increase of 18-19 min) during the interpeak period and to 27-32 min during the peak hours. The reverse journey time from Werribee to Seaholme will increase from the current 18 min to 28 min during the morning peak hours and to 23 min during the interpeak period.

I have attempted in this post to predict the change in passengers' travel behaviour due to this new timetable.

4 comments:

Daniel said...

Hi, there's no doubt Altona Loop people will be adversely affected by the changes, but can you please clarify how you're calculating these times, as I can't see the detail in the spreadsheet.

eg my reading of the timetable is, for instance:

Westona 9:50
Newport arr 10:02
Newport dep 10:09
Nth Melb arr 10:23

The next train from Nth Melb to the loop is from Craigieburn at 10:25, arriving Melbourne Central 10:29.

If that was missed (not unlikely given it's only two minutes to change platforms), there's a train from Upfield at 10:32, arriving Melbourne Central 10:36.

This makes Westona to Melbourne Central AM off-peak 39 minutes (best case scenario) or 46 (more likely). Both markedly worse than the current 30 minute trip, but not quite the 50 minutes you have listed.

For PM off-peak, eg Westona 12:50 departure...
Newport arr 13:02
Newport dep 13:09
Southern Cross arr 13:26
Southern Cross dep 13:31 (to Pakenham)
Melbourne Central arr 13:35 ... total 45 minutes, not 63.

Am I reading something incorrectly?

Also I think there's a typo in your Werribee to Seaholme list. There's no 7:04 departure from Werribee.

Thanks.

Anthony Ang said...

As you would have noted from the spreadsheet, the computations were based on the new Werribee-Williamstown-Sydenham Timetable which I have downloaded from Metro's site. I did not download the new timetables for Cragienburn and Upfield lines. On hindsight, I should have included the connections to Cragieburn and Upfield Line at North Melbourne, which I have overlooked.

Transcribing the pdf for this combined Werribee-Sydenham-Cragieburn timetable into an Excel spreadsheet is already too tedious and time-consuming. I have in fact discovered many transcribing mistakes and have amended many times. I have requested readers to inform me of mistakes in an earlier post. Thanks for your notification.

At this point of time, I do not wish to spend more time incorporating the Cragieburn and Upfield timetables, as the Metlink Journey Planner will be most accurate and reliable when it is updated to reflect the changes in May.

However, a journey time of 50 minutes was reported in the mass media much earlier than this post, soon after the new timetable was released - either this figure is supplied by Metro or somebody else has calculated this figure.

I think there will be less problem in the computations for journey time between Werribee and the Altona Loop as no other lines are involved.

I am now asking readers to be aware that mistakes do exist in the computations, which I am not aware of until someone points it out. But I am pretty confident that this new timetable represents a backslide for Altona passengers, not a service improvement and for some passengers, the effect is great.

Personally, I would not be greatly affected by the new timetable as I travel during peak hours and alight at North Melbourne.

Hope that this answers your queries.

Rachel said...

Hi Anthony. Can you tell me if the proposed changes to the Altona line are are similar to what currently happens on the Williamstown line? (i.e Willie passenger gets off at North Melbourne to catch a loop train? There are no trains direct to the loop before 8.54am, and it comes from Werribee, so a lot of us Willie people drive to Newport to catch it.)

Anthony Ang said...

Hi Rachel, you are right. The Altona service will operate as a shuttle during non-peak hours.

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