Sydney is growing. Our population is expected to reach 6.4 million by 2036 and most of the growth will happen in Sydney’s West. To tackle the surge, the State and Federal governments are building an ambitious second international airport in Badgerys Creek – but until yesterday, no-one had committed to footing the bill.

The Turnbull Government signed off on plans for the Western Sydney Airport in December last year, and will now finance the $5 billion project after Sydney Airport declined to do so. The project’s hefty price-tag is shaping up to be a bone of contention in the upcoming Federal budget announcement on May 9.

Slated to reach completion in 2018 and to open in 2026, the new airport is projected to deliver almost 9000 new jobs, and eventually alleviate pressure on Sydney Airport, which last year hosted 41.9 million passengers. The Western Sydney project ambitiously plans to double the runways and host 87 million passengers a year by 2063.

Planned 24-hour flight access is the biggest point of difference. Sydney Airport’s central location comes at a cost: planes can only land and take off from its runways between 6am and 11pm. The Badgerys Creek location means no curfew is necessary. 51 kilometres west of the CBD and 25 kilometres south-west of Parramatta, the site is also 10.5 kilometres from its closest suburban neighbour. Compare that to Sydney Airport: Mascot’s closest suburban neighbours are just 600 metres from the runway.

Convincing airlines to re-route is going to be a challenge. With Sydney Airport not involved in the development, the two airports will compete for flights. Western Sydney Airport’s 24-hour access could just be enough to entice some carriers, but airlines will be hard-pressed to give up the prestige of landing so close to the city.

To compare, Melbourne’s second airport, Avalon, lost Tigerair in 2011 and now hosts 14 Jetstar flights daily. It is plagued by its distance from the city and lack of transport options.

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The government is yet to propose any public transport options for the second airport, besides a new M12 motorway that would connect with the existing M7 as part of its $3.6 billion dollar Western Sydney Infrastructure Plan.

Plans for a second Sydney airport were first discussed in 1964.

Further details will be released in the Federal Budget announcement on May 9.