Victoria doesn’t have business cases for the majority of the suburban level crossings it is spending $6 billion to remove.
A third of all Victorian major projects are running late, with 22 of those running more than two years late.
Acting Auditor-General Peter Frost says there is a worrying lack of transparency around the billions of dollars Victoria is spending on infrastructure projects.
"Many agencies had difficulty providing basic information regarding the major capital work projects they are responsible for," Dr Frost said.
His report found the $6 billion level crossing removal program did not have a business case, although four business cases had been prepared for a collection of 19 removals.
Business cases for the other 31 level crossings will be prepared later.
Work has already started on 33 of the level crossing removals.
Four other projects worth more than $10 million each also didn't have business cases.
"This lack of transparency makes it difficult to determine whether investments have enhanced government services and whether public resources have been spent in an efficient, effective and economical way," Dr Frost said.
Dr Frost wants all government projects worth more than $10 million to provide publicly available information on planned and actual cost, spending, construction timelines and governance arrangements.
Public Transport Minister Jacinta Allan said project proposals and planning work were being done for every level crossing removal in parallel with the program-wide business case work.
"Victorians voted to remove these level crossings and we're getting it done," Ms Allan said.
"Level crossings are dangerous, they clog our roads and hold back our entire train network: the time for talk is over."
Opposition public transport spokesman David Hodgett said Victorians were being asked to trust the government not to waste money when Labor had a history of doing just that.
Greens MP Greg Barber said billions of dollars could go "down the gurgler" if the government doesn't sharpen up.
"Giving Labor a massive budget to spend is like giving a child a loaded gun. The least we can expect is some transparency about how all these billions are going to be spent," Mr Barber said.