Blue-green algae Red Alert for Mildura Weir Pool on the Murray River
Friday, December 6, 2019
The Murray Sunraysia Regional Algal Coordinating Committee has updated the red alert (high alert) warning for blue-green algae in the Murray River at the Mildura Weir. The potentially harmful algal bloom has extended and now includes the reach of the river from Lock 11 to Red Cliffs. Levels of blue green algae in other sections of the river continue to fluctuate.
The red alert level warning indicates people should not undertake recreational activities where they may be coming into direct contact with the water such as swimming, as well as domestic uses including showering and washing. Contact with the water may also pose a threat to livestock and pets.
The species of blue-green algae identified are potentially toxic and if consumed may cause gastroenteritis in humans and/or skin and eye irritations after contact.
Boiling the water does not remove algal toxins.
Livestock owners are reminded to continue to check stock water supplies for blue-green algae and to remove stock from foreshores where surface scum is visible or blue-green algae are suspected. If it is not feasible to relocate stock, it is suggested that where stock water is piped, foot valves or inlet pipes be moved as far down under the water surface as possible, where concentrations tend to be lower, as this may reduce the level of algae pumped through to stock troughs.
Blue-green algae usually appear as green paint-like scums on the water, near the edges, or as greenish clumps throughout the water. It makes the water appear dirty, green or discoloured and generally has a strong musty or earthy odour.
People should not eat mussels or crayfish from red alert warning areas. Any fish caught should be cleaned and washed thoroughly in uncontaminated water and any internal organs disposed of before consumption.
Blue-green algae occur naturally and can reproduce quickly in favourable conditions where there is still or slow-flowing water, abundant sunlight and available nutrients. It is not possible to predict how long the algae will remain at high levels. Regular monitoring will continue, and the alert will be lifted as soon as the high levels of algae dissipate.
Warning signs are being positioned at key recreational areas and will remain in place while high levels of blue-green algae are present.
People who believe they may have been affected by blue-green algae are advised to seek medical advice.
Updates about blue-green algae blooms and red level warning areas can be obtained by calling 1800 999 457 or visiting
General inquires – Elizabeth Symes – 02 6022 5326
Media Contact – Tony Webber – 0428 613 478