A scathing review of the 1700km Inland Rail project has revealed massive cost blowouts, lengthy delays and a management team without the necessary skills for the job.

The document says the cost of the federally funded project—which will build a continuous freight line from Queensland to Victoria—has almost doubled in the past two years, and now tallies $31.4 billion.

However, the report by Australia’s former Energy Security Board chairperson Dr Kerry Schott says those costs may escalate further given its exact route is still not confirmed.