Road trains bound for the Northern Territory and stranded on the flooded Stuart Highway are taking a 3,000-kilometre detour to deliver their cargo.
The highway, which connects South Australia and the country's southern states to the Northern Territory, has been closed between the remote outpost of Glendambo and the opal mining town of Coober Pedy.
The manager of the Glendambo BP, Richard Patridge, said about 30 trucks were backed up on Tuesday afternoon waiting for the road to reopen.
"This could be here for another two or three weeks at this stage, waiting for it to recede, and no-one can do nothing until the water recedes so they can check the road and see how much damage is done to that."
Mr Patridge said many of the trucks were carrying perishable items, such as fresh and frozen food.
He said by Wednesday morning, all the NT-bound produce trucks had doubled back to Port Augusta to take on an enormous detour.
From Port Augusta, they would travel through the western NSW city of Broken Hill, north through the Queensland outback and west towards Tennant Creek.
"Their employers have told them 'go the long way,' so that's what they've had to do.
"At least the food's on the way to the Northern Territory."
Flooded roads, rail cause freight chaos
The SA Freight Council's executive officer Evan Knapp said the delays would cause minor shortages in the NT and outback communities north of Glendambo.
The situation was being compounded by the flooding on the transcontinental railway line, which was closed between Adelaide and Tarcoola, he said.
"That means there is no rail freight moving from Adelaide to Darwin, or Adelaide to Perth," he said.
"Lots of people will have containers held up and causing problems for them right now."
An internal document from the Australian Rail Track Corporation (ARTC) obtained by the ABC detailed the extent of the known damage to the rail line.
The document indicates it could take up to 17 days before the line is re-opened with temporary speed restrictions in place.
However, it will take even longer to fully repair the track, with crews from NSW and Victoria arriving to provide additional support.
At least 18 sites along the rail network were washed away, with about 17 kilometres of track inaccessible to ARTC patrols because of the severe nature of the damage.
The company is working with the SES to support mine workers and local contractors who are in the area.
Councils demand disaster funding
Councils on the state's flood-hit Eyre Peninsula are calling for emergency financial support to carry out urgent repairs.
Some areas reportedly received up to 300mm of rain over the weekend, and the 160mm officially recorded in Kimba on Friday night and Saturday morning was the most ever recorded there in 24 hours.
Roads have been destroyed, fences washed away and communities and properties isolated.
Kimba Mayor Dean Johnson said it was still difficult to know the extent of the damage several days on.
Councillor Johnson said the tiny council would need government disaster support to begin the recovery process.
"We have received support in conversation, however the disaster funding streams are pretty difficult to access and there's a lot of criteria in there. We believe we'll be an exceptional circumstance," he said.
At a press conference, Premier Steven Marshall said a large number of roads were affected and it would take time to repair those belonging to local councils.
He said plans were underway to help those most affected.
"We're working very hard, in fact around the clock, to get all of our roads operational as quickly as possible," Mr Marshall said.
A spokeswoman said the Premier's office was working out what state emergency financial support might be available for councils.
"The government is also assessing eligibility for Commonwealth support under the Disaster Recovery Funding Arrangements, which is a joint initiative of the Commonwealth, state and territory governments," she said.
