NSW - Click Real Time in Rivers and Streams to get the river flow stations map of NSW https://realtimedata.waternsw.com.au/
QLD - Click Open Station in Stream Flow Data to get the river flow stations map of QLD
https://water-monitoring.information.qld.gov.au/
See also http://www.bom.gov.au/nsw/flood/index.shtml and http://www.bom.gov.au/qld/flood/seast.shtml