The Darwin ship lift project has been referred to a government committee to be investigated after years of cost blowouts and delays, with the Finocchiaro CLP Government already flagging the project will still move ahead and anticipated it will now cost “hundreds of millions of dollars” more to build.

The last estimated cost was $515 million in 2022, but could be up to $800 million by the time its completed. It was initially proposed by the former CLP government in 2015 at a budget of $100 million – which the Auditor General found was a made-up figure and that a cost benefit analysis had never been done – which ballooned to $400 million in 2019 and $515 million by 2022.

The plan has always been for the NT Government to build it for Paspaley Group to operate.

Treasurer Bill Yan blamed Labor for the delays and cost blowouts, referring it to the Public Accounts Committee of Parliament for investigation.

The PAC is expected to hold public hearings, Mr Yan said, and present its conclusions by September 2025, but Mr Yan did not say if the public will get to see the contract between the NT Government and Paspaley.

Mr Yan instead implied there is no way to get out of the contract at this point, stating that “Labor pushed the Territory past the contractual point of no return in February 2024”.

“The project is backed by a $300 million concessional loan from the Northern Australia Infrastructure Facility, which the Northern Territory must pay back in addition to our direct contributions,” Mr Yan said, on top of all the other costs taxpayers will get stuck with.

“The referral [to the PAC] is necessary given the Territory’s rising debt trajectory with net debt forecast to reach $12.3 billion by 2027-28, this is exactly the kind of project that deserves additional scrutiny.”

Mr Yan maintained the CLP Government remains committed to growing the region’s defence and maritime industries, and that the ship lift project will significantly enhance the local economy.

“We want to be open and transparent with Territorians on the costs of the project and ensure steps are taken to minimise further delays and cost blowouts,” he said.

The project has been beset by problems since its first un-costed announcement.

The government originally announced a Clough-BMD joint venture had been awarded the construction tender in July 2022 to build the ship lift, but five months later Clough entered voluntary administration. The contract was then awarded to Clough-BMD again in September 2023.

Then-opposition leader Lia FInocchiaro attempted to have the project referred to the Public Accounts Committee in 2022, but the Labor government shut that down.

Former chief minister Eva Lawler said last year that the land transfer with Paspaley had been finalised but would not disclose the cost to taxpayers, citing commercial in confidence reasons.

Paspaley is not contributing any money to the project but will operate the facility for profit once completed.