The Scotdesco community has had to order a tanker of water after its supply ran dry last week.
Scotdesco residents had been on red alert as a dry winter pushed supply to the brink and community chief executive officer Robert Larking said that ran out last week.
Mr Larking said the community was in a desperate situation and all that was left was "whatever is in rain tanks or houses", with a truckload ordered on Monday.
He said if Scotdesco was included in the nearby water subsidy zone it would provide a short-term solution, as instead of paying $1430 per tanker of water it would cost only $300.
"If the government just extended the radius to include our community, giving us access to the same long-term subsidy arrangement the Penong township receives through government for carting of water, we would at least have access to a more affordable water supply," Mr Larking said.
He said urgent correspondence with Prime Minister Scott Morrison, Minister for Indigenous Australian Ken Wyatt and South Australian Premier Steven Marshall had been made.
The state government recently sent two water experts to assess Scotdesco's plight.
Mr Larking said they were showed around the community, including the "bone dry" catchment area, and would have to file a report for Environment and Water Minister David Speirs.
Acting shadow Minister for Aboriginal Affairs Eddie Hughes said Mr Marshall needed to work out a long-term solution for Scotdesco's water security.
"The community and the local member initially raised concerns about a potential water crisis back in April this year; yet more than six months on, nothing has happened," he said.
"We are on the cusp of another hot summer and yet the Premier is content to see a whole community try and survive without easy access to fresh water."
The issue has reached federal parliament following a speech made by shadow Minister for Indigenous Australians Linda Burney in the House of Representatives last month.
Having visited Scotdesco, she said the situation was "unsustainable and unacceptable", and that a permanent solution was needed.
Mr Larking sees the potential for a long-term fix, but said a short-term solution was in reach.
"Desalination, using modern cost-effective technology including solar, could be a long-term viable option for the Scotdesco community, but in the short term, subsidised water rates are really what is needed here."