Canberra's Lake Burley Griffin has been closed due to potentially fatal levels of blue-green algae, with water quality tests showing concentrations more than 1,000 times above safe limits. The National Capital Authority (NCA) reported a significant spike over the past week, measuring a record 66 million cells per millilitre, compared to 64,000 cells per millilitre earlier this month.
The lake is closed to all swimming and whole-body water contact activities, and authorities are advising people to keep pets away from the water. NCA chief executive Gary Rake said this strain of algae, known as Anabaena, produces a neurotoxin that can slow down skeletal and respiratory muscles, potentially stopping breathing in extreme cases.
Rake warned that rowing, fishing, or boating on the lake requires extreme caution, and inexperienced users or those in unstable craft should avoid the lake entirely. The Captain Cook Memorial Jet in the central basin has been turned off to prevent algae-laden mist from being dispersed by wind.
Earlier this month, sustainability and environment commissioner Robert Neil released a report calling for an overhaul of lake management, warning that the waterway could become unusable if pollution is not addressed. The report made 17 recommendations, including better coordination among the NCA, ACT Government, Federal Government, and Queanbeyan City Council.
Rake expressed hope that rain and wind over the weekend would help clear the lake, noting that these autumn events are typically short-lived. He urged Canberrans to help improve the lake's health by not putting rubbish or leaves down drains.
