TESTS have confirmed dangerous blue-green algae in sections of the Merri River at Warrnambool.
Regular users have been notified and signs erected at access points warning of the risks to humans and animals drinking the water.
Paddling, fishing and swimming is also discouraged, with the algal bloom expected to remain for several weeks.
“Water samples were taken from the river last week and results have confirmed potentially dangerous levels of blue-green algae,” city council parks and recreation officer Terry O’Sullivan said.
“With the warm weather set to continue the river may appear a tempting relief from the heat, but we strongly discourage people from entering the water either to swim, paddle or boat.
“We will continue to test the water regularly and advise people when the bloom has cleared.”