Precautionary blue-green algae Red Alert for Lake Yarrunga
25 JUNE 2026WaterNSW has issued a Red Alert warning for high levels of potentially toxic blue-green algae for Lake Yarrunga, from Bendeela to the Bundanoon Creek arm and Yarrunga Creek arm of the lake. The alert has been put in place based on visual observation.
The Red Alert warning applies only to untreated water and will remain in place until monitoring confirms that the risk is sufficiently diminished.
People should avoid recreational activities such as swimming, water skiing, canoeing or any other activity that brings them into direct physical contact with this water body until the red alert warning is lifted. People should avoid consuming untreated water from this stretch of river and prevent pets and livestock from drinking the water.
Potentially toxic blue-green algae may cause gastroenteritis if consumed, while contact can cause skin and eye irritations. Consumption of water containing algal toxins may cause liver damage and other health problems. People who suspect they have been affected by blue-green algae should seek medical advice, and pets and livestock should be kept from drinking affected water. Boiling water does not inactivate algal toxins.
People should not eat mussels or crayfish from red alert warning areas. A precautionary approach to eating fin fish from red alert warning areas is advised. Any fish caught should be cleaned and washed thoroughly in uncontaminated water; the internal organs should not be eaten. Avoiding fishing during a bloom is the best way to minimise risk.
Blue-green algae are naturally occurring and can reproduce quickly in still or slow-flowing water when there are abundant sunlight and sufficient nutrients.
Water users should be aware of the risks associated with entering any waterway in NSW. These waters are untreated, their quality is unknown, and conditions can change rapidly. Always exercise caution and assess the risks. All untreated water should be considered unsuitable for potable use.
Visit the Shoalhaven Water website for information about the management of blue-green algae risks in the nearby treated drinking water supplies.
Updates and information about blue-green algae blooms and red level warning areas can be obtained by visiting waternsw.com.au/algae or WaterInsights.