The latest in a series of reports on the ACT Government's planned tram line was released on Thursday, just a day before the $800 million project's business case is made public for the first time.
Former Defence Department engineer and private acquisition consultant Max Flint used a 32-page report to estimate that the total cost of the city to Gungahlin light rail line over 30 years, would be between $2.13 billion and $3.06 billion, with an average annual cost to taxpayers of between $99 million to $143 million for the first two decades.
Mr Flint serves as treasurer of the Tuggeranong Community Council. The council has been critical of the project in recent months, but Mr Flint said his report was independent and released as a public service.
Without access to the commercially sensitive information, he estimates the cost to each ACT household over 20 years will be between $13,685 and $19,791, requiring a rates increase of as much as $990 each year.
The report's calculations are based on commercial interest rate levels.
The government blocked an attempt by the Liberal Opposition to refer the Capital Metro business case to a select committee on Thursday,
Capital Metro Minister Simon Corbell said Mr Flint's report was not credible.
"The report by Mr Flint contains many serious errors and large miscalculations caused by incorrect assumptions, misinformation and a limited understanding of how public private partnerships work," he said.
The government would issue the final business case for the tram line on Friday.
"The [business case] was produced using analysis performed by internationally renowned economic advisers EY and will provide accurate information and economic reasoning behind the project," Mr Corbell said.
Opposition transport spokesman Alistair Coe said Mr Flint's paper highlighted the likely cost of stage one to be in excess of $100 million each year.
"The ACT government is burdening current and future residents with a massive financial liability for a service that will only cater for a fraction of the city," he said.
Clarification: An earlier version of this report suggested Mr Flint's report was prepared by EY. The government's business case was prepared by EY, not Mr Flint's report.
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