Extreme Blue-Green Algae Levels Force Lake Burley Griffin Closures
Testing conducted by the National Capital Authority has revealed that blue-green algae levels in Lake Burley Griffin have escalated from high to extreme in the Central Basin area. This alarming increase follows the appearance of a visible green film on the water's surface, prompting immediate public health advisories and activity restrictions.
Health Risks and Activity Bans
The National Capital Authority has issued a stern warning, stating that exposure to the contaminated water poses an increased risk of adverse health events. Symptoms may include skin and mucosa irritation, flu-like symptoms, and gastrointestinal illness. As a result, swimming, bathing, and novice sailing, canoeing, and rowing have been prohibited in the Central Basin area near Regatta Point.
Only individuals with experience in sailing, canoeing, or rowing are advised to participate in activities in this zone. Event organisers have been instructed to ensure participants are fully aware of the alert level and associated risks, and to provide adequate showering facilities post-events.
Broader Impact on ACT Waterways
The contamination extends beyond the Central Basin. Yarralumla Beach East is categorised with high blue-green algae levels, also closing it to swimming. At Yarralumla Beach, medium levels mean the area remains open, but susceptible individuals could experience symptoms. Pet owners have been cautioned not to allow animals to swim in or drink lake water where algal scums are present.
In other ACT managed waterways, some areas are closed due to bacteria alerts that were in place on Monday, March 30. Additionally, WaterNSW has reported blue-green algae in the Murrumbidgee River, downstream of Tantangara Reservoir to the ACT border. The ACT government is actively monitoring this situation.
Historical Context and Monitoring Efforts
This incident echoes a similar event at the end of 2025, when rain flared blue-green algae in Belconnen waterways, resulting in the deaths of two dogs. Dog owners have since called for improved signage around government-managed lakes during such alerts. The National Capital Authority collects test samples each Monday to monitor lake conditions, with results typically reported on Thursday or Friday of the same week.
As authorities work to manage the crisis, residents and visitors are urged to heed all warnings and avoid contact with affected waters to prevent health complications.
