The stormwater pipe had deteriorated near Mannum on the Murray River on Tuesday afternoon, flooding a nearby rowing shed and causing water to bubble up through a concrete slab.
The situation continued to deteriorate, with emergency services doorknocking 12 households at 2am to warn them to evacuate.
Three households sought emergency accommodation, while two remained in at home.
One of the remaining two left on Thursday morning.
SA State Emergency Service chief Chris Beattie said about 60 emergency service workers had attended overnight and pumping efforts to contain water levels continued.
"That will continue while we look at options to cap the pipe on the river side of the levee," he told reporters.
A commercial diver was contracted to assess the broken pipe.
Mr Beattie said the failure would not impact the integrity of the broader levee network.
Premier Peter Malinauskas again confirmed the flood's peak had passed the town of Renmark near the Victorian border, and noted it was moving faster than expected along the Murray River.
"In a way that in one respect is good news," he said.
"The sooner the peak passes through the system, the better that is."
Mr Malinauskas said authorities hoped to see inflows at the Victorian border down to 150 gigalitres by mid-January.
Inflows at the border are currently around 180 gigalitres per day, compared to between usual flows of 15 to 18 gigalitres per day at this time of year.
Ahead of New Year celebrations, the premier reminded holidaymakers that a ban remained in place for all recreational activities on the Murray River.
"That is there solely for the public safety of people," Mr Malinauskas said.
"Having said that, it has always been our stated objective to remove those restrictions on the Murray as quickly as we possibly can."
The State Emergency Centre has developed a working group to develop a timeline and criteria set to ease restrictions as conditions improve.
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