Where does southeast mainland rivers originate from?

Southeast mainland rivers mainly originate from the Great Dividing Range, a 3,500-kilometer mountain range that runs parallel to the east coast of Australia. The Great Dividing Range acts as a natural barrier between the eastern coastal plains and the drier inland regions of the country. As rain falls on the eastern slopes of the range, it accumulates and forms numerous rivers and streams that flow eastwards towards the Pacific Ocean. These rivers play a crucial role in shaping the landscape, supporting ecosystems, and providing water for human settlements in southeastern Australia.