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?).