The Barwon River is temporarily closed following a blue-green algae outbreak.
Corangamite Catchment Management Authority (CCMA) closed the river with warning signs placed along affected stretches of waterway to notify the public.
A combination of hot weather, low water flows and high nutrient levels in the Barwon River have contributed to the outbreak, CCMA said.
Testing on February 28 showed high levels of toxic blue green algae in two sampling locations.
During algal outbreaks, people and their pets should avoid contact with the water. It is strongly advised that users of the river do not come into physical contact with the water, due to the potential health risk posed by blue green algae.
Contact with blue-green algae can cause skin rashes, eye and ear infections, vomiting and diarrhoea, mouth ulcers, sore throat and asthma symptoms.
Corangamite CMA advises that people should avoid eating shellfish or fish caught in contaminated water.
CCMA will notify the public as soon as conditions change, and the river is safe to be reopened to the public.
Anyone experiencing a reaction should seek medical help.
Blue-green algae blooms can be seen with the naked eye across the water surface.
However blue-green algae toxins are colourless and odourless and can remain at dangerous levels in water even after the blooms have disappeared.
For information or to report a suspected blue-green algae outbreak, contact CCMA on 1800 002 262 or ccma.vic.gov.au
