Melbourne on Transit: Building Melbourne's Useful Network Part 1: Caroline Springs (and index)

Two weeks ago I unveiled the Melbourne public transport frequent network map. It showed where in metropolitan Melbourne there was all-day public transport service frequent enough to be useful for travel across the day.

That had several uses. For example you could find where you could go to or connect without waiting long. Or it could help in deciding where to buy or rent a home. For those it’s better than the PTV local area maps that do not distinguish between the useful frequent routes and less useful occasional services.

Frequency maps can also be handy if you are a developer, urban planner or transport advocate.

By showing where the frequent service is these maps help you see where the best locations to build (or approve) denser developments are. Places near several frequent routes would be attractive to those who value good transport access. Developments in such areas may need less provision for parking than those remote from the frequent network. Whereas you would avoid high densities in less accessible places. The 10 and possibly 15 minute Sunday map would be most useful as, if a service is frequent on Sunday it will be frequent on all other days.

Transport advocates, particularly in densifying or historically unserved areas, may also find these maps useful. If their suburbs have grown rapidly, experienced overcrowded buses and/or has demograpics suited to high public transport usage a strong case may exist to increase frequency.

This exercise, which will run each Friday for several months, is to identify Melbourne's 'Useful Network' deserts. I will also identify where and how the Useful Network can be expanded.

Defining the Useful Network

The first job is to set a threshold service level for the 'Useful Network'. A strict frequency threshold (like 10 minutes for a 'Frequent Network') neither tells us much nor is cheap to fix since so few routes comply. Whereas a lax threshold (eg hourly) is not useful for many trips. Although it may be suitable when advocating a basic service where there is nothing.

Thus the threshold needs to be somewhere in between.

I've adopted a 20 minute weekday peak and interpeak threshold frequency for the 'Useful Network'. All trams meet it. As do most train lines. Most bus routes do not. But there's many bus routes just outside the threshold that could be upgraded to Useful Network frequencies relatively cheaply. Thus extending Useful Network coverage to (say) a million more people would be comparatively affordable. How? That's for later.

As important as frequency is span of hours. For this I'll use the existing minimum standards for buses. That is service until 9pm seven days per week.

These requirements are not perfect. For example I'm vague on weekend frequencies. And buses would be more useful if they started one or two hours earlier (especially on weekends) and finished a little later. But for simplicity I'll stay with the existing minimum standards. You can see the existing 'Useful Network' as coloured lines when the 20 minute layers for train, tram and bus are selected from the map below (use top left icon to select or top right to view map in new tab).

ADDENDUM MAY 2019: Since writing the above I've come across the minimum service standard for SNAMUTS network analysis. They also had to define minimum standards for a useful network. Their 20 minute interpeak weekday threshold matches the Useful Network described here. However SNAMUTS is stricter for weekends (30 min versus my 60 min) but less strict for span (none versus my 9pm). If you look at their composite accessibility map (last done in 2014) you will see it is similar to my 20 minute network map.

Where to from here?

Each Friday I'll feature one area typically comprising three or four suburbs. I'll briefly discuss what's there now. Then I'll suggest ways to expand the Useful Network. Unserved areas, sparsely populated areas or isolated pockets between Useful Network route will not be covered. Such areas may justify a less frequent local coverage service. These can be added once a network's core routes, that is its Frequent Network and Useful Network services, have been established.

Useful Network 1: Caroline Springs

The Caroline Springs area comprises 1990s - 2000s suburbs about 25km west of Melbourne. Housing is mostly detached. Although blocks are not particularly large and there is some higher density near the Caroline Springs Town Centre. Rail access is mostly by bus to the Sunbury Line. The new Caroline Springs station to the south outside the suburb is served by country trains and has no significant walkable catchment.

The area currently has two Useful Network corridors. Both are relatively recent additions. The first is Route 420 between Sunshine, Deer Park and Watergardens (shown above in blue). It was added in 2014 as part of the Brimbank network review. Route 420 is one of the few services to operate every 20 minutes seven days per week. It's timed to meet trains at Sunshine Station.

Also quite new is the red line from Sunshine to Burnside. This is a two route corridor comprising routes 426 and 456. Both start at Sunshine and overlap to Burnside. 426 then goes north to the Caroline Springs Town Centre while 456 goes west to Melton. Both routes normally operate every 40 minutes. Even offsetting provides a 7 day 20 minute combined service, timed to meet Sunbury line trains at Albion or Sunshine. This corridor features wide operating hours with services to Caroline Springs Town Centre finishing at midnight.

Potential Caroline Springs Useful Network extensions

1. Route 460 rescheduling: Most striking on the map is the long white corridor from the station up Caroline Springs Bvd and along Gourlay Rd. That's Caroline Springs' main spine, with the town centre, shops and numerous schools along it. The northern end is not far from the busy Watergardens station and town centre. The absence of the Useful Network in the area is not for the lack of a route; Route 460 from Caroline Springs Station to Watergardens serves it all. The only problem is its current timetable (a previous timetable used to be better). While the 460 normally has three buses per hour, their uneven spacing (sometimes with gaps approaching an hour) excludes it from the Useful Network.

A characteristic of Caroline Springs is that its bus routes are quite wide apart. There is also limited road permeability to the east as there are few crossing points across creeks and a former urban growth boundary. In addition a sizable proportion of the population work in the CBD so would benefit from better access to trains. These provide patronage opportunities for the routes that are there.

2. Route 418 upgrade: The next priority for a Useful Network upgrade is likely to be Route 418 along Taylors Rd. This is the most direct means to reach Metro trains from the Caroline Springs Town Centre. Thanks to the 2014 Brimbank network review it has a good direct alignment. In addition its catchment to the east includes a high low income population who tend to be heavy users of buses throughout the day. Because Route 418 peak buses already operate approximately every 20 minutes, upgrading interpeak buses to also operate every 20 minutes should be relatively cheap.

3. Train frequency upgrade: Weekday midday train frequencies at Caroline Springs Station are currently 2 trains per hour, spaced slightly unevenly. This drops to every 60 to 80 minutes on weekday afternoons and weekends. This is why the line does not feature on the Useful Network. An upgrade to every 20 minutes (to Melton) would greatly improve the station's usefulness and boost patronage on the southern portion of bus Route 460.

4. Other Useful Network extensions: Other extensions to the Useful Network around Caroline Springs are possible. However they are harder due to interdependencies with rail projects or other bus routes.

For example upgrading Route 426 to a 20 minute off-peak frequency would make it part of the Useful Network in its own right and better connect Sunshine with the Caroline Springs Town Centre. However this would leave an inefficient duplication with Route 456 to Sunshine unless it was shortened to terminate at a local station such as Caroline Springs or Deer Park. As this would remove a fast direct connection between Melton Town and Sunshine this might only be done after the Melton line is electrified or at least greatly upgraded in frequency.

Similarly something along Hume Dr from Watergardens could fill in some Useful Network gaps. That currently has Route 461 running along it. However Route 461 heads south, going through some smaller streets to Caroline Springs Town Centre. Later, as development spreads west and routes are reformed then Hume Dr might deserve its own more frequent Useful Network route.

Service priorities for expanding Caroline Springs Useful Network

1. Reschedule Route 460 to provide a more consistent 20 minute weekday service while connecting with trains at both ends. By itself this would massively expand the Useful Network for very low cost.

2. Upgrade Route 418 to operate every 20 minutes during the day between the peaks.

3. Upgrade train frequencies at Caroline Springs Station to provide a consistent 20 minute or better service on weekdays and weekends (as a precursor to electrification).

4. Investigate other routes or corridors such as Route 426 and Hume Drive for future Useful Network upgrades as train services improve and the area develops.