A state report critical of the city’s proposed $5.5 billion rail transit project uses flawed reserarch and represents an “appalling waste” of taxpayer dollars, Mayor Peter Carlisle said.

The report, released yesterday by the state Department of Transportation, uses erroneous assumptions about the state’s economy and potential ridership for the 20-mile train, Carlisle said.

He also called the report biased, noting that one of the authors is a known anti-rail advocate.

“Therefore, it is no surprise the report is a predetermined, anti-rail rant,” Carlisle said in a news conference at his office. “Spending one-third of a million dollars for this shoddy, biased analysis is an appaling waste of our tax dollars.”

The report predicts the project is “likely” to face cost overruns of more than $1.7 billion and that ridership is likely to be “substantially lower” than currently forecast.

It was commissioned by the Gov. Linda Lingle at a cost of $350,000 from the state Highways Fund and is not part of the Federal Transit Administration’s approval process. 

Lingle ordered her financial analysis last spring to determine whether the rail project was feasible given the state’s economic struggles. She said she wanted an objective assessment because the project is being financed by Oahu taxpayers as well as the federal government.