The Linking Melbourne Authority, the agency that was to oversee the East West Link, has virtually no work to do after the Andrews government dumped the $6.8 billion project.

The authority's chief executive Ken Mathers is paid about $350,000, one of its contractors got more than $430,000 in the past financial year, and its most recent annual report shows it had about 60 staff in June.

But it is unclear what this workforce will now do, and the Andrews government is unable to say - leading the opposition to dub Roads Minister Luke Donnellan "the roads minister with no roads projects".

Mr Donnellan on Wednesday said the authority would be kept, but could not say what work it would do now that the East West Link had been dumped.

The Linking Melbourne Authority was established to deliver EastLink under the Bracks government, and later oversaw construction of Peninsula Link.

The authority's one remaining job is to manage the Peninsula Link contracts, but it will hand this role to VicRoads this financial year.

Treasurer Tim Pallas on Monday released the East West Link business case, which the Linking Melbourne Authority prepared with the Transport Department.

The business case showed the tunnel would have taken 56 years of toll revenue to pay for its construction costs, and would have lost 55¢ for every $1 invested in it.

Mr Pallas described the financial black hole the project would have left for Victorians as "public malfeasance and fraud of a massive scale".

Mr Donnellan defended the Linking Melbourne Authority, saying that "the fraud that was the East West Link was driven by the Napthine government itself".

And he said the government was setting up Infrastructure Victoria and Projects Victoria to ensure "the robust governance of all its infrastructure projects".