The move comes after the government declared a state of emergency.
Under the curfew no one would be able to enter the CBD unless they are part of the Gita Emergency Response Team.
"The curfew furthers protect people and property and police have asked for public understanding and common sense," Mr Caldwell said.
Police have also issued key safety messages to the public:
· Keep yourself and your family safe
· Keep off the road
· Stay at home if it's safe
· Get to an Evacuation Centre as soon as possible with food and water