The NSW opposition has called for an upper house inquiry into the ongoing flood disaster, after parliament voted in favour of an independent inquiry last week.
"One of the reasons why we want to have an upper house inquiry that reports quickly (is) not to assign blame, not to make ... scapegoats," Labor leader Chris Minns said on Thursday.
"(It's if) we're in a position when if we can make reforms or shine a spotlight on things that have gone wrong, it can be corrected before the next natural disaster hits.
"I don't know whether that was as a result of faulty gauges, or incorrect information that was handed to the SES, but we can't have this situation repeated.
"We need to have a clear line of authority in relation to who issues these evacuation warnings."
Frustration has grown in the regional city of Lismore after an initial evacuation order, issued Tuesday afternoon, was cancelled then reinstated about 3am on Wednesday.
NSW SES Acting Commissioner Daniel Austin on Thursday defended the actions of the SES, saying the right decisions were made at the time.
He added the Northern Rivers had been struggling with infrastructure issues, including at the SES building.
Mr Austin said the initial evacuation order was for flooding of the Wilsons River at Lismore and the likely overspill of the flood levee, which did not eventuate.
"As a result, that risk (was) no longer present (and) we decided in consultation with a number of people, including people locally, to remove the evacuation order and allow people to return to get on with the recovery effort," he said.
It took until Wednesday for an exceptional level of new rainfall, not previously predicted, for the levee to overflow.
"We do not have the joy of hindsight," Mr Austin said.
To the southwest in Lismore, flood levels continue to fall after the Wilsons River peaked at 11.4 metres, below the predicted record height of 12.
"That's good news for the community this morning," Flood Recovery Minister Steph Cooke said on Thursday.
"However we are regrouping as we look at recovery efforts as the water starts to recede.
"The weather system is making its way down the east coast, and we will see other communities impacted as it moves south over the next couple of days."
Some 30,000 people in NSW were affected by 20 evacuation orders earlier on Thursday, with 523 people housed at 20 evacuation centres.
However the orders for Mullumbimby, Kyogle, Nambucca Heads and Tumbulgum were revoked on Thursday afternoon.
Meanwhile the search continues for missing aged care nurse Anita Brakel, whose car became trapped in floodwaters in Monaltrie, south of Lismore.
No trace of Ms Brakel or her car has been found since she disappeared on Tuesday about 10pm.
A day after Byron Bay was also hit with unexpected flash flooding, frustrated business are anxious to reopen their doors.
"This summer, it's just been raining constantly, like constantly," Main Street Burger Bar co-owner Jack Tupper told AAP.
"And when it does rain, it's so intense. It's frustrating because we own the business. It's hard, all the days that we are shut. We're still paying rent.
"We're going to try and seat people because there's not many venues that are going to be open, and there's a lot of people in town," Mr Tupper said.
Major flooding continues on the Wilsons, Richmond, Clarence, and Orara rivers, and at Coraki, Woodburn and Grafton, while moderate flooding continues on the Hastings, Nambucca and further south along the Macleay, Bellinger and Kalang rivers.
Australian Associated Press
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