Blue-green algae Red Alert for the Macintyre River at Lake Inverell

Blue-green algae Red Alert for the Macintyre River at Lake Inverell

23 January 2020

A red alert level warning (high alert) for blue-green algae has been issued for the Macintyre River at Lake Inverell. Recent sampling by WaterNSW has shown high levels of a potentially toxic species. Inverell Shire Council have installed warning signs in key locations.

A red alert level warning indicates that people should not undertake recreational activities where they may be coming into direct contact with the water such as swimming, watercraft or other water-based activities. Contact with the water may also pose a threat to livestock and pets.

Stock and domestic users in this immediate stretch of the Macintyre River should exercise a high level of caution and seek alternate water supplies. Stock and domestic users further up and downstream along the river should apply caution and inspect water sources for algae scums. It is highly recommended to avoid extraction of or stock watering from areas affected by blue-green algae.

Park users along the Macintyre River are advised to avoid all contact with the water and to restrict pets from drinking from or entering the water.

People should not eat mussels or crayfish from red alert warning areas. Recreational fisherman are advised to avoid fishing from red alert warning areas. If fish are caught, they should be cleaned and washed thoroughly in uncontaminated water and any internal organs disposed of appropriately.

The algae identified is potentially toxic, however town water supplies remain safe as the treatment processes will remove the toxins. Boiling the water will not remove algal toxins. If consumed without appropriate treatment, they may cause gastroenteritis and other health conditions. Skin and eye irritations may occur after contact with the water.

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. Blue-green algae occur naturally and can reproduce quickly in favourable conditions where there is still or slow-flowing water, abundant sunlight and sufficient levels of 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.

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 visiting – or calling 1800 999 457.

General inquires - Tracy Fulford - 02 6763 3910, Hannah Took – 0436 653 394

Media Contact – Tony Webber – 0428 613 478


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