https://www.g-mwater.com.au/water-resources/catchments/storage-levels River Basin Maps | ETA Unknown
Current Musing: Murray and Darling River Systems (On hold - COVID-19)
Convergence of the Culgoa and Barwon Rivers to form the Darling River

River Basin Maps

Map of the basins and major rivers, including flow information can be found below. Other resources for river flows can be found official direct sources (links given below the map).

Minimum flow is around 2 Cumecs and a good flow is considered to be above 10 Cumecs. The latter is my personal minimum. Flows are estimated from the BOM river feeds that give river heights only and I used historical records to correlate these heights to the historical flows. Some flow heights are estimates only.

No flow
Height where flow ceased was assumed to be zero if no historical data was found.
Poor flow
A level that is likely too low to kayak, with a flow under 2 Cumecs.
Low flow
A level that maybe paddlable? The flow was calculated to be under 10 Cumecs.
Good flow
A flow over 10 Cumecs.

Data pulled from Bureau of Meteorology.

Official Flow Sources

MDBA Murray Darling System Overview
An excellent instant view of the Murray Darling system. Includes tributaries such as the Mitta Mitta, Ovens, Goulburn and Murrumbidgee rivers as well as others. This should be your goto resource if you are considering doing the Murray River!

The quality of the flows in the following sites are based on historical percentiles. Since the average flows from many inland rivers are fairly poor, look for high flows in the following maps (i.e. 80% or 90% above average flows).

QLD Stations
Water Monitoring Information Portal run by the QLD government.
NSW Stations
WaterNSW real time data overview.
VIC Stations
DELWP real time data overview.
SA Stations
WaterConnect from SA government.

Map vector data is a mix of manually created content and basin boundaries supplied from Bureau of Meteorology and Geoscience Australia (© Commonwealth of Australia 2014)

Rainfall Observations and Forecasts

The Bureau of Meteorology provide a number of various tools to look at forecast rainfall including:

Rainfall Observation
Map of daily, weekly and monthly rainfall observations can show potential inflows.
Rainfall Forecast
Raw data from their computer models to estimate 5 day rainfall amounts. Useful to use in combination with local area forecasts.
Rainfall Outlook
A longer term outlook looking ahead up to 3 months.
ENSO Outlook
La Niña, a negative IOD and a positive SAM all point to a wetter forecast for the eastern coast.
Landscape Water Balance
This can provide an insight to what runoffs can be expected with rain. If there is a water deficit, much of any rainfall will be sucked up by the dry soil, before feeding the creeks and streams.