A little over a month ago, the town faced an existential threat when the Currowan fire roared over the hills and destroyed dozens of homes in Conjola Park.

On Monday, residents faced a new evacuation order, this time for flooding.

"That's absolutely exhausting," Ms Nelson said.

"All that fear you're carrying, all that tightness in your chest, the tension in your neck, the difficulty sleeping - that is a real physical thing. Validating those feelings is an important step, to accept that you are tired, that you are irritable."

Ms Nelson said people who have faced multiple traumas, such as fire and flood, should give themselves permission to feel awful.

The New Year's Eve fire saw many residents burnt out of their Conjola Park homes relocate to holiday houses in low-lying Lake Conjola, where on Monday they were urged to evacuate again.

"They must be wondering what will come next," Ms Nelson said.

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Feelings of powerlessness in the face of threat were stressful but small steps taking action helped.

"Action leads to post traumatic growth. It makes us feel stronger."

Strengthening connections, with family, friends and the wider community was also important for recovery.

If after a few weeks people were still struggling to have positive thoughts, Ms Nelson urged them to seek help.

"Go to your GP and ask for a referral to a psychologist."

She said there should be no shame in this.

"This is real and getting help to walk through a really difficult period should be no different to, say, going to a mechanic to fix your car."

Ms Nelson works for an Aboriginal community centre in Sydney, where she deals with a lot of trauma.

She has also worked in post-conflict zones in South Sudan and Uganda.