Australia’s most populous state of New South Wales has issued more evacuation orders following the worst flooding in decades.

The New South Wales State Emergency Services responded to 640 calls for help on Saturday night, including 66 for flood rescues.

New South Wales Premier Gladys Berejiklian says hundreds of people have been rescued from the waters.

Evacuation orders have been issued at multiple locations on the Mid North Coast in the northeast of the state, which Berejiklian said was experiencing a one-in-a-100-year event that will continue into next week.

The Warragamba dam, west of Sydney, started overflowing and so far, 13 evacuation centres have been opened.