On Nov. 5, a dam at an iron ore mine in southeastern Brazil collapsed, unleashing 50 million cubic meters of waste water that flooded nearby communities and killed more than 10 people.
But the disaster didn’t end there. In the following weeks, the gunky waters funneled into the Doce River, a major waterway whose name means “sweet” in Portuguese. The sludge flowed downstream for more than 400 miles tinting the river a chocolate hue before reaching the Atlantic. Along the way, it contaminated water used by thousands of people to drink, farm, and fish.
Economic and environmental losses remain unquantified. The mud has already killed thousands of fish, likely by choking them to death with its fine sediment.
Mine owner Samarco, a joint venture between Vale and BHP Billiton, set aside one billion reais ($260 million) in an emergency fund. Green Peace says that’s nowhere near the amount needed to repair the damage.
The companies have said the waste is mainly composed of sand and does not pose any health risks.
The UN, however, said on Nov. 25 that evidence shows the sludge released by the failed dam contained “high levels of toxic heavy metals and other toxic chemicals.”
“The scale of the environmental damage is the equivalent of 20,000 Olympic swimming pools of toxic mud waste contaminating the soil, rivers and water system of an area covering over 850 kilometers,” John Knox, UN Special Rapporteur on human rights and the environment, said in a statement.
The Doce River, he added, is now considered dead by scientists.
Here is a timeline of the mud’s devastating course over the past 20 days:
Nov. 6—Officials in Bento Rodrigues, a village near the mine, scramble to assess casualties after the torrent of waste flooded the remote region. Samarco says in a statement it hasn’t determined why the dam burst or the extent of the disaster. Reuters/Ricardo Moraes
Nov. 8—Hundreds of rescue workers dig for victims in Bento Rodrigues aided by special tools and dogs. Two deaths are confirmed. Reuters/Ricardo Moraes.
Nov. 10—The mud continues to spread. Six bodies have been found and 22 are still missing. Reuters/Ricardo Moraes
Nov. 19—Environmentalists and fishermen downstream from the mine rush to rescue wildlife before the arrival of the liquid waste. Protective barriers are installed on the banks of the Doce River and diggers clear a path at its mouth so the mud can exit into the ocean more quickly. Reuters/Ricardo Moraes
Nov. 21—The gunk reaches the mouth of Rio Doce in the coastal village of Regencia, a popular surfing spot some 400 miles east of Bento Rodrigues. The collapse of the dam displaced 500 people and left a quarter of a million without running water. Reuters/Ricardo Moraes
Nov. 22—As it floods the Rio Doce, the muck sullies miles of wildlife habitat. Scientists say the sediment it leaves behind could redraw the course of streams as it hardens, lower water oxygen levels and make the riverbanks and farmlands it touched less fertile. Reuters/Ricardo Moraes
Nov. 23—The mud spills into the sea. Reuters/Ricardo Moraes
Nov. 25—The mud is still on the move and now threatens protected forest and habitat at the Abrolhos National Marine Park, according to UN. The agency reprimands Samarco and the Brazilian government for not doing enough. “There may never be an effective remedy for victims whose loved ones and livelihoods may now lie beneath the remains of a tidal wave of toxic waste, nor for the environment which has suffered irreparable harm,” officials say in a statement. Reuters/Ricardo Moraes