Sailors, ecologists and local fisherman joined together on August 8 to protest the authorities' failure to clean up the heavily polluted Guanabara Bay, where the Olympic sailing event will take place in next year's Games.
The bay is often spoken of as "dead" given its fetid, sewage-filled waters, spewing up mounds of rubbish onto its shores.
Protesters on Saturday, however, sought to bring attention to the human and animal life in and around what they called the "live bay," in order to pressure authorities to tackle its decade-old pollution.
When Rio bid to host the 2016 Olympic Games, the city trumpeted the clean up and said it would cut the amount of raw sewage flowing into the bay by 80 percent.
However, it has since admitted it is unlikely to meet that target, and privately commissioned tests of the water quality where athletes will be competing revealed last week a high level of disease-causing viruses.
Brazilian Olympic sailor, Isabel Swan, who won Bronze at the Peking Games in 2008, said that rubbish floating in the bay still poses a real risk for athletes.
"The rubbish is particularly dangerous for fast boats because they have great momentum and if they are stopped by plastic, by rubbish, it could slow down the speed all of a sudden and athletes could be hurt. It depends on the size of the rubbish, but it is dangerous. I think that by the time of the Games, the issue if solid rubbish will be resolved," Swan said at the protest.
She added that the waters where she competed in Peking suffered an outbreak of algae just two months before the Games and that the authorities were able to resolve the issue in time.
The pollution of the Guanabara Bay is not just an issue for Olympic athletes, protesters were keen to point out.
It is a serious health risk for residents of Rio. Biologists last year said rivers leading into the bay contained a super bacteria resistant to antibiotics that cure urinary, gastrointestinal and pulmonary infections.
Earlier this year, the Rio de Janeiro state government said the amount of sewage treated before reaching the bay had risen from 17 to 49 percent, but over half, therefore, is still what has been called "raw."
Previously a source of livelihood for the indigenous sambaquis, the bay is now a source for local fishermen, whose activities are increasingly put at risk by industrial and human waste poured in the waters.
According to environmentalist, Sergio Ricardo, industrial proliferation is justified by the idea of the "dead bay," entering into a vicious cycle for the state of the water.
"We are certain that the bay is alive. For the government, the Guanabara Bay only serves as a deposit for rubbish, sewage and industrial waste. The government's environmental organ justifies all this expansion of petrol rigs and industry with the idea that the bay is dead. But this bay is alive, if you walk around it you will see people fishing and bathing in these precarious conditions," said Ricardo.
The waters along Rio's Atlantic coast, including Guanabara Bay, have been polluted for years and successive governments have spent hundreds of millions of dollars on attempted clean-ups to little effect.
Reggae singer and poet Da Ghama says that the civil society must use the Olympic moment as an opportunity to pressure officials to finally make a change.
"Unfortunately funds are not used for this issue of the Guanabara Bay. Many governments have gone by which included this in their budget, but nothing has been done. It is up to us as artists, the civil society to put the pressure on for a solution to be found, making the most of the Olympic moment, to first mobilise society itself to put the pressure on," said Da Ghama, going on to sing his pleading message for society and governments not to destroy the nature around them.