We're getting a better idea of what Sydney's controversial road project WestConnex will really cost

The WestConnex route

The NSW state budget announced yesterday posted a record $2.1 billion budget surplus, aided in no small part by billions of dollars in stamp duty from Sydney’s soaring property market, but it seems that housing isn’t the only thing in the city where the costs are rising rapidly.

The NSW budget papers reveal that the estimated cost of the 33km WestConnex motorway between Parramatta and Beverly Hills has jumped by another $500 million in 12 months to $15.4 billion, and Sydney property prices are partly to blame.

When the landmark project was announced in 2012 by Infrastructure NSW (INSW) and the new O’Farrell Coalition government, the estimated cost was $10 billion.

A spokesperson for WestConnex told Business Insider that the original estimate was in $10-$13 billion in 2012 dollars.

“After further refining the project, the WestConnex Business Case Executive Summary detailed the cost at $11-$11.5 billion – again in 2012 dollars and well within the INSW $10-$13 billion range,” they said

“These are all 2012 dollars – the cost if the project could all be built in one year. As the project is taking nearly a decade to progressively build, the equivalent out-turn cost is $14.9 billion.

“Recent improvements in project scope, to provide the best connections for a future Western Harbour Tunnel and a Southern Extension, bring the total expected out-turn investment to $15.4 billion. The additional investment brings additional benefits.”

Fairfax Media reports that the government is spending a record $7.5 billion on transport infrastructure, which includes a new underground train station at Barangaroo, and $1.7 billion for WestConnex.

Fairfax says the latest additional costs for WestConnex are the result of the increased cost of property acquisitions, and a stub to link the motorway to another future motorway connection in southern Sydney.

The $15 billion project has received fierce resistance from residents in Sydney’s inner west concerned about unfiltered exhaust stacks from the underground motorway being placed beside their homes, while 180 homes will be compulsorily acquired by the NSW government.

The toll on the motorway, when it’s completed in 2023, is likely to be around $11.

* Editor’s note: This story was originally titled “The cost of Sydney’s controversial WestConnex motorway has blown out by a staggering $5 billion in 3 years”. It has been amended to reflect the views on the costings from WestConnex.

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