Looking from domestic airport station, Brisbane Airtrain, towards airport terminals

The idea of a train from Melbourne Airport to the CBD is never out of the news for long in Victoria. Now the Committee for Melbourne, which sees a mass transit link to the airport as one of Melbourne’s nine strategic needs, is holding a forum on the topic next month.

So I thought I’d have a stab at setting down what I see as the main issues around this topic (in no order):

When will the airport link be needed? Infrastructure Victoria doesn’t expect it will be required for at least 15 years; it thinks the existing bus system can handle forecast demand with some upgrades to roads to provide priority access. It’s possible though that forecast demand might change, either to bring the horizon closer or push it further out.

Should it be a shuttle service for the exclusive use of airport travellers? A dedicated service minimises problems with baggage and requires fewer stops, but it also limits the potential benefits. The alternative is a service like Sydney’s Airport Link that also serves metropolitan travellers.

Should the airport service be integrated with the wider transit system? The Government proposes it should share tracks with Melbourne Metro; the advantage is many travellers in the south-eastern suburbs would get a one-seat journey to the airport. Some argue this would limit capacity for suburban services and propose instead a dedicated airport line terminating at Southern Cross Station.

What route will it take? This requires optimising several variables, especially travel time (important for the B in BCA), cost of construction, patronage, and impact on the efficiency of the metropolitan rail system. The cost to construct the lowest cost option using the reserved (mostly) at-grade route is likely to be at least $3 Billion. Some options involve extensive tunnelling and could cost a lot more.

Should it be routed to support intensive urban redevelopment? Building the line via the former Footscray munitions site and/or Essendon Airport could significantly increase housing supply and generate revenue provided the development potential of the increase in accessibility is fully exploited. The cost of construction would be higher and the net benefit of relocating existing uses would need to be established.

Should it be routed to support development of dormitory regional centres? This would benefit country travellers and help relieve growth pressures in Melbourne, but has wider implications. The net benefit of decentralising residential growth compared to current growth strategies would need to be assessed. Another issue is whether there’d be enough country travellers to justify the cost.

What will be the key benefits? It’s likely the lion’s share of benefits would come in the form of faster, more predictable trips, mainly for business travellers. History indicates it will have little impact on traffic congestion or on the pressure for motorway widening. Benefits from lower emissions, less pollution and fewer crashes are likely to be relatively small.

What mode share will it win? Sydney’s Airport Link claims close to 20% mode share but Brisbane’s, which is arguably a better parallel with Melbourne, has circa 10%.

Who will own and/or operate the line? There are a number of possible models with varying degrees of government control and accountability.

How will ticket prices be set? This is likely to have significant implications for the level of use. The usual practice with airport rail, even when operated by government, is to set prices to recoup capital and operating costs. The polar alternative is to set them in line with current myki prices.

What is the scope for related travel demand policies? How road access and airport parking are priced will have a big impact on patronage and the financial performance of the airport link.

What about non-CBD travellers? Most airport trips by Melburnians originate or end outside the city centre. The warrant for providing new transit options for trips from the eastern and western suburbs requires investigation. This highlights the need for a comprehensive assessment of airport access options (see Is an airport train to the CBD the whole story?).

This list isn’t exhaustive but they’re what I see as the main issues. There are other important matters that I think aren’t as central at this time, including choice of mode, location of terminals and stations, the potential of airport-related business agglomeration, the impact on SkyBus and taxi operations, and more.

The most important point in my view is to conceive “the problem” in terms of overall airport accessibility rather than only as a single mass transit link to the CBD. That implies a suite of measures across infrastructure construction, infrastructure pricing, and land use and regulatory policies.

It’s terrific the Committee for Melbourne is facilitating discussion. The Government needs to put a big and early effort into investigating, assessing and planning options for the airport; this is a great opportunity to get it right before some half-cocked politician locks the State into an ad hoc solution.