The likelihood of water quality issues typically reduces across the cooler months. Conditions remain favourable for blue-green algae within many Basin waterbodies, with some areas still experiencing elevated salinity from earlier northern inflows.
Summary of key water quality issues
Water quality within the Basin is monitored by individual States. Any site-specific alerts, warnings or advisories are issued by those respective States.
- Blue-green algae: There remains an algal risk across much of the Basin, particularly at some key waterbodies in NSW and Victoria including the Menindee Lakes, lower Darling (Baaka) and Lake Eildon. SA continues to see elevated levels along the River Murray near the border, and in Lake Alexandrina.
- Elevated Salinity: Parts of the Menindee Lakes and the lower Darling (Baaka) continue to see elevated salinity levels. SA’s southern Coorong is also currently experiencing elevated salinity levels that are impactful to biodiversity.
More information on algal levels can be found from the respective State government on our Report water quality issues or fish deaths page.
| Location | Algal blooms | Acid sulfate soils | Blackwater | Elevated Salinity | High turbidity | Low dissolved oxygen |
| Coorong | Unlikely | Unlikely | Unlikely | Possible | Unlikely | Unlikely |
| Lower Lakes | Almost certain | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murray (SA below Lock 1) | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murray (Waikerie to Lock 1) | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murray (SA border to Waikerie) | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murray (Lock 10 to SA border) | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murray (Euston to Lock 10) | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murray (Yarrawonga to Euston) | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murray (Hume to Yarrawonga) | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murray (upstream of Hume Dam) | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Edward–Wakool | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murrumbidgee (Upper) | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murrumbidgee (Mid) | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Murrumbidgee (Lower) | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Lachlan (Upper) | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Lachlan (Lower) | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Grampian–Wimmera–Mallee | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Campaspe River | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Avoca–Loddon River | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Goulburn–Broken | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Ovens | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Kiewa | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Lower Darling/Baaka (Menindee to Burtundy) | Likely | Unlikely | Unlikely | Possible | Unlikely | Unlikely |
| Menindee Lakes | Likely | Unlikely | Unlikely | Possible | Unlikely | Unlikely |
| Barwon–Darling | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Upper Macquarie–Cudgegong | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Lower Macquarie–Castlereagh–Bogan | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Namoi | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Gwydir | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Border Rivers (including Moonie) | Possible | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Condamine–Maranoa | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Culgoa–Balonne–Narran | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Paroo | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |
| Warrego–Nebine | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely | Unlikely |