An outbreak of blue-green algae at Forest Lake has turned the water green, emitted a strong stench, and led to concerns about wildlife deaths and potential health risks for the local community.
Community Alarm over Lake’s Condition
Residents of Forest Lake have expressed growing frustration and disappointment over the worsening state of the lake since mid-2024, when increasing algae levels caused the cancellation of the annual Dragon Boat race.
Many locals, have linked the poor water quality to the frequent deaths of wildlife in the area, describing the lake as “disgusting.” One resident noted the unbearable odour and expressed disappointment at the declining appeal of the once-popular spot for relaxation.
The blue-green algae infestation, caused by high levels of nutrients such as nitrogen and phosphorus, thrives in still water under warm, sunny conditions. This toxic bacteria can pose serious risks to humans and animals, including skin irritation, nausea, vomiting, and muscle cramps.
Wildlife is equally vulnerable, with fish and native species becoming ill or dying from prolonged exposure.
A Recurring Environmental Challenge
This is not the first time Forest Lake has faced an algae crisis. In 2019, a similar outbreak turned the lake’s water swamp-green and caused odours detectable up to 150 metres away. The ongoing issue highlights deeper ecological problems linked to urban stormwater runoff, which often carries fertilisers and other pollutants into the lake.
Response and Efforts to Restore the Lake
Council is addressing the situation with a collaborative, multi-pronged strategy. Teams from various branches, including Public Space Operations and the Natural Environment and Sustainability Branch, are working together on solutions. A spokesperson explained that recent above-average rainfall and warm weather have exacerbated the problem, creating ideal conditions for the algae bloom while complicating mitigation efforts.
Key actions include scientific analysis of water quality data and consultations with external organisations to trial potential treatment methods. Mid-December has been marked for further water testing. Proposed long-term measures include installing aeration hardware to improve water circulation and dissolved oxygen levels, thereby preventing stagnation and reducing the likelihood of future blooms.
Council has also engaged with the Queensland State Government to align its actions with state guidelines and explore additional treatment options. Community members are encouraged to reduce fertiliser use in their gardens to minimise nutrient runoff into the lake.
Published 14-Dec-2024