A year's worth of rain was dumped on north Queensland in a week and Sunday night was described by authorities as the worst so far as locals prepare for a "long, hard week" ahead.

A total of 1100 residents were evacuated overnight, the SES received 850 calls for help in the 24 hours to Monday morning, rescue crews saved 18 people and one looter was arrested by police.

An aerial view of the flooding in the Townsville suburb of Oonoonba on Monday morning. Credit:QFES

Townsville Mayor Jenny Hill vented her frustration after some residents in areas predicted to be inundated, had to be doorknocked and asked to leave twice.

"You can’t say you weren’t warned something might happen," she said.