Final report on Lake Bullen Merri algae trial

Published on 24 January 2024

An 18-month trial has not solved blue green algae issues in Lake Bullen Merri.

Corangamite Shire Council recently received the final report on the Lake Bullen Merri Blue Green Algae Control Pilot.

The project tested ultrasonic equipment intended to break up algae cells.

Manager Environment and Emergency Lyall Bond said an independent scientific advisor had analysed the Pilot which was finished early last year.

“They found the process was not effective on the three key measures,” Mr Bond said.

“There was no strong evidence of a change in algae densities from the previous or following year.

“There was also minimal disruption to the dominant cyanobacteria species.

“Sampling showed no significant changes in cell walls and cell counts across the study. “The report concluded technology and pontoon reliability would need to be optimised if future pilots or trials were to be considered.”

The ultrasonics did not remove the nutrients from the lake, which is one of the main contributing factors to blue green algae blooms and further work would be beneficial to understand nutrient cycles at the lake.  

The final report can be found here.

The Mayor Kate Makin said it was disappointing that the pilot did not provide a solution to the lake’s algae issues.

“Now that Council has undertaken this pilot, we are hopeful that the lake managers will consider trialling or implementing other control programs.  

“Lake Bullen Merri is a really special place for a lot of fishers and recreational boat users from across the shire and beyond.

“We want to see it in a healthy condition for use by our residents and visitors.”