How many suburban Melbourne job centres could be connected with a circular railway?

Activity centres, national employment clusters and job hubs: there's many names for these places and we have quite a lot of them in middle-Melbourne. The lead image above has been taken from one of Alan Davies' earliest blog posts on Crikey from 2010.

The heat map represents the major job hubs - based on 2006 census data - that are located further than 5 kilometres from Melbourne's CBD. All in all, Alan Davies found that three quarters of Melbourne's jobs were located more than 5 kilometres from the CBD and of those suburban jobs, 20% of them were concentrated in 31 suburban centres (depicted on the heat map).

As a child - early primary school age - in order to shut me up/distract me from whatever it was that was driving my mother mad at the time, I was schooled on how to map read, street-directory style. Yes kids, maps used to only exist on printed matter!

Mum would open a Melways, point out train stations, show me how to follow the railway lines across the corresponding pages so I could then find more stations and you can see how a 200-300 page Melways could keep a kid busy. It also helped that dad was geography teacher and we had shelves of atlases and street directories from other cities in the house, not to mention a large drawer of maps in one of the filing cabinets.

30-odd years later this map-upbringing has manifested itself in my tendency to stare at any map I see for very long periods of time, and at some point, if I stare for long enough, the patterns and shapes start emerging.

That's the first shape I saw after staring at Alan Davies' 2010 job hub map: a circle running from Altona to Sandringham, one that bisects the majority of the suburban job hubs in Melbourne.

Footscray, Moonee Ponds, Preston, Northland, Heidelberg, Doncaster, Box Hill, Deakin Unviersity, Monash University, Mulgrave and Moorabbin all are either directly under the path of the circle or not far from it.

The biggest clusters without any decent rail service on that map have had proposals and studies to link them - Monash University/Mulgrave & the Rowville rail line study, Melbourne Airport and its very own study - yet connecting them to the radial rail network, is it enough?

Earlier this week on Tuesday, Mark profiled the SJB-designed 12-14 Nelson Road planning application that's recently hit the desk of council planners at Whitehorse and the diagram above paints a fascinating potential future for Box Hill.

Box Hill's built-form density has traditionally been commercial or retail buildings and it's no secret that the cat's out of the bad when it comes to high-density residential development. However as evidenced by the ATO's new office tower, there appears to still be an appetite for bigger and better offices in the area.

On the other side of the city, Moonee Ponds' density is set to get a new height and bulk benchmark with Caydon recently receiving approval via VCAT for their first foray in Hall Street. The ATO once again are a large tenant in the area, not to mention Foxtel's main Melbourne offices bookend the precinct.

Both the Box Hill and Moonee Ponds images depict scenes that may come to fruition in future and while you can argue that both are richly served by public transport now, should we not ask the question: what if they were connected to their adjacent, non-CBD job hubs?

Sydney has its "global arc" stretching from the airport through the CBD to Parrmatta via the lower North Shore and Macquarie Park. Melbourne could have a "global semi-circle"!

The single yellow line, plus the short spur in the north connects with many of the job centres present on Alan Davies' 2010 map, especially the large university campuses and the industrial/commercial areas they're generally located next to: Monash University and Mulgrave, Deakin University and Burwood, La Trobe University and the Northland/Bell Street commercial area, Victoria University Sunshine campus and Sunshine/Braybrook.

Regionally significant shopping (and job!) centres like Highpoint, Northland and Doncaster would be connected to a mass-transit service; Southland would get a second connection. All conventional rail lines except Werribee and Williamstown extend the reach of the circular line to nearly ever corner of the metropolitan area.

The circular railway links three of the six Metropolitan Planning Authority-defined employment clusters: one existing (Monash) and two emerging (La Trobe and Sunshine). Incidentally, one of the other existing clusters (Parkville) will be linked with the Melbourne Metro project, and with a realignment of the existing Werribee line, another emerging cluster (Werribee East) could be directly serviced by heavy rail; refer to the Werribee area on the map above.

And perhaps most crucially, many new residential areas get a rail service for the first time, especially in the east.

Focusing on Monash University and Mulgrave for the moment, at present 30 minutes by train from its nearest station - Clayton - will get you as far as Berwick, Cranbourne or the CBD. With a circular metro line such as that shown above, those three destinations would link deeper into the entire cluster a single train change; Sandringham and Heidelberg/Doncaster to Monash/Mulgrave would then be thrown into the "30 minute city" mix also.

Furthermore adding the Rowville rail line as shown above - via Chadstone and the Alamein line - places like Scoresby/Rowville and Swinburne University/Hawthorn/Camberwell are all connected by high quality mass-transit to this mega suburban job hub.

For those interested, the circular line as shown on the map measures 58.5 kilometres with a further 5 kilometres for the La Trobe University spur. In what could be a phased construction approach, the segments measure: Clayton to Heidelberg 23.2km (Phase 1), Heidelberg to Sunshine 23.3km (Phase 2) and Clayton-Sandringham 12km (Phase 3).

And finally, some more food for thought. Milan's automated M5 Metro line was recently extended by 7km at a cost of €872 million ($1.2 billion Australian dollars in 2011, when the contract was signed) which paid for all civil, fit out and technical/electrical "hard" infrastructure costs.

The earlier rolling stock order (€35 million in 2006 / $60 million Australian dollars) from phase 1 catered for both the initial line and the recently opened extension. The order was for 12 3-4 car trains capable of carrying up to 600-800 people on 3 minute peak frequencies.