Suburban rail loop – how can this mistake be prevented?

The suburban rail loop promised by the Andrews government addresses a real problem; a good public transport system must have orbital as well as radial routes.

But it's the wrong answer, at the wrong time and in the wrong place. If it were on a strategic plan with construction anticipated to commence several decades from now – say when the level of demand justifies a costly mass-transit line on this alignment – it would make a lot more sense than starting construction within four years as the government has promised.

But of course, this isn't a case of wise planning for the future; it's an explicit and unequivocal commitment to commence construction by 2022, motivated entirely by political convenience.

What's wrong with that? Here are some of the ways.

Generational commitment

First, it's essential to understand that this is a huge commitment. The government's quick and dirty estimate of the capital cost to build 90 km of track and 15 stations is $50 billion. We know from experience with mega-projects that that is almost certainly a significant under-estimate (see Why do the worst infrastructure projects get built?).

But even taking it at face value, it's way more than enough to double the size of Melbourne's tram network. It's more than the estimated cost of building a High-Speed Rail line from Sydney to Melbourne. It's around three times the $17 billion the Rudd government spent on the BER program to avoid Australia being strangled by the GFC.

This is big money. It's a generation's worth of funding that wouldn't be available for other new public transport projects in Victoria, or for initiatives in other key areas of the state budget, like health and education.

Higher priority public transport projects

Second, there are other potential projects that would deliver much greater net benefits and should accordingly be given priority over the loop. That's not surprising; this project is a pure political play announced in the run up to last year's election. It was invented on the run, without serious analysis and without reference to Infrastructure Victoria, the body set up by the Andrews government supposedly to de-politicise infrastructure spending.

The glaringly obvious alternative is Melbourne Metro Stage 2, as well as a heap of smaller but critical projects – like track improvements, signalling upgrades, more trams, and higher frequency bus services – that would improve reliability and increase capacity.

The list of priority projects for rail in Melbourne proposed by advocacy group Rail Futures is instructive. Although it has its own (more modest) version of a suburban loop, Rail Futures says the immediate priorities ought to be electrifications, additional rolling stock, duplications and extensions of existing lines, and new light rail routes (see exhibit, and also Isn't long-term planning for urban public transport a no-brainer?).

Negative net benefits

Third, the net benefits of the suburban rail loop will almost certainly be negative. This is not only because of the extraordinary cost; the other side of the equation is that it won't attract many travellers and the majority of those who do use it will shift from other public transport services.

Unlike radial train lines, where high levels of traffic congestion and high parking costs in the city centre make driving uncompetitive, the loop passes through the middle ring suburbs where driving is much more attractive. According to VISTA, 89% of motorised trips in Melbourne's middle ring suburbs are made by private vehicles.

In addition, the loop will have only 15 stations spread along 90 km, so the service isn't going to attract many walk-ups, who're usually the majority of train users. That compares with the existing Melbourne rail system, which has 219 stations for around 400 km of track.

The first stage slated for construction starts from the tiny shopping centre of Cheltenham and traverses 6 km underground to the next station at Clayton. There's a 9 km gap between Box Hill and Heidelberg stations; 10 km between Reservoir and Fawkner stations; and 13 km between the Airport and Sunshine stations.

The average travel time for a trip by car in the middle ring suburbs is 20 minutes. Most potential travellers living near the loop won't go to one of the 15 loop stations by bus or car, they'll simply drive all the way to their destination.

The government contends the loop will link suburban activity centres and drive jobs growth. The problem, though, is that only three or four of them qualify as major suburban job concentrations. Taken together, all fifteen centres account for a mere 5% of Melbourne's jobs (see Is Melbourne's promised loop rail line justified by jobs growth in suburban centres?).

A 90 km underground heavy rail line is a vastly over-engineered solution relative to any plausible level of patronage. It'll probably make sense one day, but not yet.

And even if the politically-inspired claim made by the government that it will shift 200,000 travellers per day out of their cars when it's completed in 2050 is taken on trust, that would amount to less than one percentage point of mode shift. A small pay-off for $50 billion and 28 years.

The wrong solution

Fourth, it's the wrong solution. The ability to travel orbitally with efficient connections to major radial routes is critical to a good public transport system, but the loop will be just a single mass-transit line in an urbanised area that extends circa 35 km around the CBD (but over 50 km in the south and south-east).

It will be of limited value to the great bulk of Melburnians who don't live near one of the 15 stations. Moreover, the paucity of stations means the bulk of travellers who live near the route must use another mode to access the nearest station at the start and end of their trip.

What's really needed is a metropolitan-wide 'grid' of multiple radial and orbital lines that maximises the number of travellers who can access high-frequency public transport by foot. A mammoth sum like $50 billion could fund a 'spider's web' of fast light rail and BRT routes every 2 km (say) with dedicated rights-of-way and priority at intersections (see Isn't there a much, much better way to do cross-city public transport?).

It would be a more effective way of providing orbital routes across all of Melbourne than a single suburban rail line. It would cost less, deliver greater benefits sooner, and provide many more public transport users with improved accessibility.

How can we help?

I expect wiser heads within the Andrews government know this is not the right project; at least not for some decades yet. The government needs help to walk back from this mistake.

It's probably too late to do anything about the whopping $600 million the government and a (future) Shorten federal government have jointly promised to spend on business planning and preparatory works by 2022. There's a case for preserving an alignment for the future, but the government has no idea if this is the best route or if something closer or further from the CBD would be best.

There are at least two actions that must be taken, starting now.

First, public transport advocates, academics, planners and the media need to be vocal in pointing out this is the wrong project (for now) and that there are many higher priorities that demand investment. So far almost all of them have nodded it through approvingly, save for mild complaints about the lack of a business plan. But not all rail projects are good just because they're rail; a bad project is a bad project.

Second, the same group also needs to give the government room to back away. If it proposes modifications – say to use light rail instead, or a longer time frame, or if it tries to sell the airport rail line as the first stage of the loop – it should be supported, not mercilessly hounded for failing to deliver on an election promise. It needs to be given a pass to reinvent the promise as something better; perhaps, as a 'grid' of medium capacity transit as proposed above (see Isn't there a much, much better way to do cross-city public transport?).

This is a silly, careless and cynical promise that, if implemented, could put real improvements to public transport in Melbourne on the back-burner for decades. It's not the way to improve travel for public transport users or to increase transit's share of travel from its current desultory level i.e. 10% and static (see Where to with transport in our capital cities?)