Record-breaking rains over three days have left regional roads cut and flood warnings in place for large parts of South Australia.
A number of towns recorded their biggest daily falls for January in what the Bureau of Meteorology said was a significant and unusual rain event for SA.
The Eyre and Yorke peninsulas along with parts of the state's north and west coast received the biggest drenching which began on Friday and continued into Sunday.
Winter Springs on Eyre Peninsula had the most with 228 millimetres falling over the three days.
Nearby Kimba also had 160mm over a 24-hour period, its biggest daily total since the start of records in 1967.
The State Emergency Service said multiple roads across the affected areas remained damaged or covered in debris including the Olympic Dam Highway between Pimba and Woomera where large sections of bitumen had been washed away.
Department chief executive Tony Braxton-Smith told a parliamentary committee on Monday that crews were working to reopen the highway with the damage also limiting access to Roxby Downs and the Olympic Dam mining community.
"As you know there's been record rains. I think it's been characterised as a one in 100-year event," he said.
Mr Braxton-Smith said other roads affected for varying periods over the weekend included the Sturt, Lincoln and Eyre highways.
He said those roads were being progressively reopened.
Meteorologist Kylie Egan said a very slow-moving low-pressure system with deep tropical moisture and a surface trough were the drivers of the "extraordinary" rainfall event.
"The slow-moving pattern resulted in a multi-day rainfall event which is rare for South Australia," she said.
Premier Steven Marshall said it was too early to tell the full extent of the damage across SA.
"Our priority is to get those roads and other critical infrastructure repaired," he said.
"We want to get behind and support those communities that are most impacted.
"We want to see what the options are for leaning in and supporting those communities at this pretty tough time."
Australian Associated Press