Just before 1pm, Moruya Fire and Rescue captain Mark Gould said crews arrived to see a small house on fire.

"It was fully engulfed on arrival - it was destroyed completely," he said.

Moruya Fire and Rescue worked to extinguish the blaze and was supported by Moruya and Broulee RFS crews.

"We were there for approximately three hours," Mr Gould said.

"The biggest problem was that there was no reticulated water. RFS had to keep ferrying water back from hydrants."

Police said the occupant, an 88-year-old woman, sustained minor burns to her face and hands and went to Moruya hospital for medical treatment.

Police said an investigation was underway to determine the cause of the fire.

READ MORE: Eurobodalla Council facilities closed for NSW lockdown