At least $30bn will be spent building a construction yard to eventually build nuclear submarines for Australia under the Aukus agreement, despite doubts over the deal.

The prime minister, Anthony Albanese, announced on Sunday the federal government had pledged $3.9bn as a “down payment” to secure the future of the submarine construction yard in the northern Adelaide suburb of Osborne.

The government hopes the project will create 10,000 jobs in design and construction, as well as up to 1,000 apprentices a year at an onsite training facility.

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The staggering cost of the facility is laid bare by the sheer size of the footprint being designed.

Enough steel to make 17 Eiffel towers, as well as 710,000 cubic metres of structural concrete, will be used in the construction of the 420 metre-long fabrication hall.

The future of Aukus has been under a cloud for months since the US announced it would review the terms of the agreement.

But the prime minister dismissed concerns that the promised shipyard would never see an Aukus vessel.

“This is in the interests of the United States, in the interests of the UK and in the interests of Australia,” Albanese said on Sunday.

The $30bn price tag comes from an estimate provided by Australian Naval Infrastructure, the government’s hand-picked company tasked with delivering the Aukus facility.

As well as construction, the new yard will include capability for the testing and commission of the submarines.

An estimate for how long the yard would take to complete or whether the $30bn figure will increase was not confirmed.

Defence has become a boom industry for South Australia, with the country’s first missile factory recently opening in Port Wakefield.

Osborne already hosts the existing facilities for Collins-class and Hunter-class subs.

“There were 1,200 people working at Holden when it closed – 4,000 will be required to construct this facility,” said the state’s premier, Peter Malinauskas.

“It is hard for South Australians to genuinely comprehend the amount of high-paid skilled work that has come our way.”

The announcement of a decades-long infrastructure commitment comes just over a month out from the South Australian state election.

A poll on Wednesday showed Labor holding a 61-39 lead over the Liberals on two-party-preferred terms.