Minister for Water Resources, Drought, Rural Finance, Natural Disaster and Emergency Management David Littleproud said the Government had listened to the concerns of farmers in delivering on this election commitment.
"I promised this thorough inquiry after hearing from farmers as I travelled up and down the Basin," he said.
"They're going to have a look at every facet of the water market to make sure we can give those farming families confidence that there's fairness in it."
Mr Littleproud believed politicians should not be involved in the inquiry as it is a complex issue.
"There's unintended consequences if Governments rush and overreach," he said.
"I've got to get the independent umpire with all the tools to get it right.
"Government's don't interfere in the marketplace unless there's an inequity - if there is, we'll act, but I need the independent umpire to do that, not politicians."
If the ACCC find there is trading between people who do not use the water and recommend changes, Mr Littleproud said he would be willing to work with the State governments to make those changes.
"14 percent of water licenses that are owned at the moment are owned by individuals and corporations that don't own land - now is that the original intent of what happens when we separated water from land?" he said.
"That's the question the ACCC will look at, and then we'll have a mature conversation with the state."
Mr Littleproud believed the State Ministers have worked well as a team to implement the Murray Darling Basin Plan so far.
"I have to say to my state colleagues they have done a fantastic job over the last 18 months with that respect," he said.
Let's continue to build on that and then work through whatever recommendations we get at both a Federal and State level, to make sure farming families get a fair crack."
The Government has asked for an interim report to be delivered by May 31st.
"That will give enough time for public consultation," Mr Littleproud said
"I expect the ACCC to sit out there and listen - to sit in machinery sheds like I have and listen to what farmers are telling them about the practical realities of this market, and to get an understanding of it, and then to get to the bottom of it."
The final report will be delivered by the end of November 2020.
The terms of reference announced today apply across the whole of the Murray Darling Basin.