More than 30,000 residents of Sydney and its surrounding areas have been told to evacuate or prepare to abandon their homes, as Australia’s largest city braces for major flooding.

Parts of the city of five million people are facing a fourth flooding emergency in a year and a half after torrential rain since Friday caused dams to overflow and waterways to break their banks.

“The latest information we have is that there’s a very good chance that the flooding will be worse than any of the other three floods that those areas had in the last 18 months,” Emergency Management Minister Murray Watt told Australian Broadcasting Corp on Monday.

The current flooding might affect areas that managed to stay dry during the previous floods, Watt added.

New South Wales state Premier Dominic Perrottet said 32,000 people were affected by evacuation orders and warnings.