• Melbourne
  • Seasonal

Algal bloom on Ornamental Lake

Ornamental Lake is currently experiencing a cyanobacterial (blue-green) algal bloom which is being closely monitored by expert staff. The Gardens advises all visitors and their dogs to avoid contact with the lake system water at this time as the alga may cause allergic reactions in the skin and eyes.

Kylie Regester, Acting Director of Melbourne Gardens, explains that algal blooms are a natural phenomenon in water bodies like lakes, reservoirs and rivers.

“Algal blooms can occur in water bodies when there is an increase in concentration of algae combined with hot weather,” she said.

“When this happens the water appears green and it often looks like there’s a scum on the surface of the water.

“Usually, the blue-green algae dissipate when the weather cools down.”

This is not a new phenomenon for Melbourne Gardens, with blue-green algal blooms recorded in Ornamental Lake at various times since 1986.

Monitoring of the blue-green algal population will continue in association with Melbourne Water and the Department of Environment and Primary Industries.

Treatment options include continued development and maintenance of wetland planting and recirculating the lake water through pumping. The Gardens will not be using any chemical-type solutions as our first priority is protecting the biodiversity of the area.