Transport for NSW said on Friday it would re-open most of the parklands on Tuesday after the final removal of asbestos from the site, which was closed in January after the discovery of bonded asbestos in mulch.
The discovery prompted the closure of schools, hospitals and other parks as part of the Environmental Protection Authority's largest probe since it was set up in 1991.
While most of Rozelle Parklands would open to the public, its wetlands, managed by Transurban, would remain fenced off because of the discovery of blue-green algae, Transport for NSW said.
"While the wetlands are not for swimming or recreational use, as a precaution, temporary fencing will remain in place around the affected area and signage will be erected, to ensure everyone's safety," it said in a statement.
Inner West Council mayor Darcy Byrne said locals were fed up after problems with the Rozelle Interchange, the asbestos contamination and now an algae bloom.
"Transurban have questions to answer, they've had responsibility - care, control and management of these wetlands - for six months now and we want to know what their testing regime has been," Mr Byrne told reporters at the park.
"We're writing to Transurban today to insist that they provide immediate responses about how this will be fixed, what they have done to protect public safety up to now and we're giving them a deadline of Monday before we take legal action of our own.
"We want the CEO of Transuban to come down and meet with our community immediately to discuss how this is going to be treated and the park made safe."
Transurban has been contacted for comment.
Blue-green algae can cause health problems for people and domestic animals that come into contact with it including skin irritations, nausea, vomiting, muscle weakness and cramps.
In March, the state government pledged to double penalties for environmental crimes in NSW in the wake of the asbestos contamination.
