A leading constitutional lawyer from New South Wales has been appointed by the South Australian Government to lead its royal commission into the use of Murray-Darling Basin water.

Premier Jay Weatherill announced he would establish the royal commission last month, after allegations of corruption and water theft from upstream emerged earlier this year.

The Government released its draft terms of reference for public consultation, and announced it would be seeking to appoint Bret Walker SC as commissioner.

Mr Walker recently represented former federal water minister Barnaby Joyce in the High Court, during the Federal Parliament citizenship scandal.

Mr Weatherill said the royal commission and its broad proposed terms of reference would help South Australia get "to the truth" and single out those responsible for "undermining" the Murray-Darling Basin Plan.

"The power of a royal commission is the way in which it makes forensic findings that we can rely upon," he said while visiting Loxton in the state's Riverland.

"There are lots of allegations and lots of suggestions and what we need to know is the truth, and Bret Walker SC will get to the truth.

"This is going to put the pressure on a lot of people in the upstream states [that] say they're doing the right thing."

The terms of reference revolve around the implementation of the Murray-Darling Basin Plan, environmental water targets, and compliance and enforcement issues.

Riverland community 'resilient' through Murray plan

Loxton Waikerie Mayor Leon Stasinowsky said the Riverland community had been rocked by the allegations of upstream theft, and wanted to see the issue resolved as soon as possible.

"We're lucky we're a really resilient community that's fought on, but we're just getting back on track now to where we sort of were before [the plan was agreed to]," he said.

"We were assured that everyone was on the same page.

"If [theft and corruption is] happening in New South Wales what hope have we got in getting those flows down through here?"

Liberal Member for Chaffey Tim Whetstone said the Premier was playing politics and he has not responded to the party's call for bi-partisan support.

"Sadly the premier has excluded the South Australian liberal from any consultation, any bi-partisanship when it comes to the Murray River," Mr Whetstone said.

"And he's meeting stakeholders, commodity groups and they are under the impression they are they to contribute to those terms of reference. So it really is tokenism."

Inquiry could become federal: Premier

Mr Weatherill said he hoped the state based inquiry would eventually lead to a federal royal commission being established.

"I wouldn't be surprised if ultimately it became a federal inquiry," he said.

The State Government said the royal commission was expected take about a year to complete, and would cost a "few million" dollars.

The terms of reference will be finalised next month, with inquiries to begin in the new year.