Activists alleging decades of neglect and the repeated failure of authorities to make good on clean up promises have effectively killed one of Rio de Janeiro’s most iconic waterways staged a protest on Saturday. The protesters held a symbolic “burial of Guanabara Bay, the sewage-filled waters where Olympic sailing competitions are to be held. The demonstration was held on one of the city’s most polluted beaches, Botagofo, which is enveloped in a sulphuric stench, dotted by household rubbish and looks out over the iconic Sugarloaf Mountain. READ MORE: Zika virus? Rio’s filthy water is more of a worry, says Hong Kong’s windsurfing golden girl Lee Lai-shan Protesters placed a rubbish-filled mock coffin on the fetid sands, which they draped with black cloth. The event’s organiser, biologist Mario Moscatelli, said it was among the last-ditch efforts to force state authorities to keep their promise of cleaning up the bay before the August Games. “This is an environmental crime,” said Moscatelli, wearing chest-high rubber overalls and industrial goggles as he waded out into the dark waters to pluck out floating rubbish. “If this is happening here, at the picture postcard symbol of Rio, imagine what’s happening in the interior of the country.” He added that around seven months ago he accused Rio’s state water utility Cedae of flooding the bay with untreated sewage. Moscatelli has several videos shot near the site of the protest showing a tidal wave of sewage pouring out from a Cedae facility and into the waters of Botafogo Beach. As neither federal nor state prosecutors have taken any action on the matter, Moscatelli said he intended to bring his complaint again. Sewage pollution has become a major issue in the run-up to the Olympics since last year, when an independent study showed astronomical viral levels from untreated sewage in all of Rio’s water venues, where 1,400 Olympic swimmers, rowers, sailors, canoeists and triathletes will compete. READ MORE: Crew filming Olympic Games test event in Rio de Janeiro robbed at gunpoint In Rio’s Olympic bid, authorities pledged to drastically reduce the amount of sewage flowing into the bay before the tournament, but with very little progress to date, officials now acknowledge the targets won’t be met. Athletes have expressed alarm not only over the sewage but also floating rubbish, which could potentially cause catastrophic accidents or cost teams medals. Earlier this week, the local O Globo daily ran a photo of what appeared to be a severed arm floating in the bay, but the details behind what happened were unknown.