Algae blooms in Hardy Inlet are being monitored by the Department of Water and Environmental Regulation (DWER) as recent warm weather has increased the growth of algae.
Two algae blooms – a macroalgae bloom around the Augusta township and a phytoplankton bloom around Molloy Island - have been mapped by the department as a part of fortnightly water quality monitoring.
DWER Aquatic Science Branch Manager Malcolm Robb said macroalgae is a type of algae that can be seen with the naked eye.
“Macroalgal blooms are a common occurrence in South West estuaries at this time of year,” Mr Robb said.
“They are sometimes referred to as nuisance blooms as they interfere with recreation, impact the aesthetic enjoyment of our estuaries and smell as they decompose. But they are not harmful to human health.”
Recent sampling around Molloy Island has also shown the presence of microscopic blue-green algae, or Lyngbya.
“Some species of Lyngbya can cause irritation to the skin and DWER works with the Department of Health and the Augusta-Margaret River Shire to manage potentially harmful algae blooms,” Mr Robb said.
“In this case, signs have been erected to advise people not to swim or recreate in affected water.”
Algae blooms are caused by a combination of warm weather and nutrients being washed into the estuary via surrounding waterways. Reducing nutrients entering Hardy Inlet is the long-term solution for reducing algal blooms.
The department is working with local farmers and catchment groups, including Lower Blackwood Landcare, through the State Government’s Healthy Estuaries WA, to reduce nutrients entering seven key South West estuaries including Hardy Inlet.
The $25 million program was launched by Water Minister Dave Kelly in June 2020, and includes funding for on-ground work to keep nutrients on farms where they can be used for plant and pasture growth – protecting our waterways and the productivity of local farmers.
Residents living next to the inlet can also help by using minimal, slow release fertiliser on home gardens, planting native plants and being water efficient.
DWER will continue to monitor water quality and algal blooms in the Hardy Inlet and work with other agencies and local government to respond to algae blooms.
