TWO monitoring floats were launched at the Valley Lake last week as a step towards improving water quality for recreational use.
At a cost of about $14,000, the water monitoring floats are part of a project being undertaken by the City of Mount Gambier to address algal blooms which occur in the Valley Lake during summer due to increased water temperature and light conditions.
“We wish to find the most appropriate way to eliminate these blooms and reduce summer cyanobacteria and algae counts to below guideline levels outlined within the National Health and Medical Research Council guidelines for managing risk in recreational water,” City of Mount Gambier Environmental Sustainability Officer Aaron Izzard said.
“The first step in attempting to improve the water quality is to try to understand the dynamics of the lake and the floats will assist with this.”
The floats have come from New South Wales based water investigation and solutions company, Photon Water, and will monitor the water quality at a variety of depths during the next four months.
“Characterising and measuring what is in the water, and then looking at good control, is a really logical way of approaching it; doing it in the slow and scientific way,” Photon General Manager – Water, Ian Phillipps said.
“This water management approach will ensure that scientifically principled and verified engineering solutions are considered and applied to fix the problem.”
Mr Phillipps said the floats will measure temperature, salinity and oxygen, and water samples would be analysed to determine the species of algae and bacteria.
“The floats will sit out on the lake until winter and then be removed and placed back out again in spring,” he said.
The lake can still be used for recreational purposes during the investigation period as the floats are situated out of the way of watercraft and are clearly visible to ensure the safety of water users,” Mr Izzard said.
The results will influence the second stage of the project which will involve implementing water quality control solutions to reduce algal blooms.
“Coming into next summer season we should have a good understanding and hopefully some control methodology in place to improve the water quality,” Mr Phillipps said.
“Treatment of the algal blooms will lead to a healthier lake and natural environment,” Mr Izzard said.
“Reduction of algal blooms will also be beneficial for fish and invertebrate species that inhabit the lake.
“We also hope that by reducing the algal blooms that the lake may then be utilised for a wider variety of recreational purposes.”
