Standing on her wooden canoe, a machete in her hand, Yuly Velásquez hacks away at reeds matted with blackened sludge. Close by, a burst oil pipe has released a slick of crude into the San Silvestre wetlands in Barrancabermeja, Colombia’s oil city, choking the water and its wildlife.
“The destruction is immense,” says Velásquez, president of Fedepesan, a sustainable fishing organisation. “For the fish, the animals and flora, it means immediate death.”
With its swamps, lagoons and forests, Barrancabermeja sits in a biodiversity hotspot – the home of endangered river turtles and manatees, and the wetlands act as a corridor for roaming jaguars.
Yet it is also Colombia’s biggest oil town. Gas flares shoot into the sky from a labyrinth of tanks, pipes and chimneys, producing up to 250,000 barrels of crude oil a day and serving 80% of the national demand for fuel.
For decades, this refinery, which is operated by the majority state-owned company Ecopetrol, has also been accused of releasing oil and toxic waste into nearby rivers and wetlands, and of causing leaks that pollute the region’s fishing grounds.
Environmental authorities and residents say the impact has been catastrophic: fish populations have crashed, water quality has deteriorated and numbers of manatees – once regarded as a guardian spirit of the wetlands – are now thought to be on the brink of collapse.
A report published last year by the Environmental Investigation Agency, a campaign group, and Earthworks, a US organisation that focuses on the harmful effects of the mineral and energy industries, identified more than 800 records of “major environmental damage” caused by Ecopetrol, with most occurring from the mid-1990s to the mid-2010s.
The report, based on a trove of leaked files known as the Iguana Papers, also described a “web of deceit and cover-ups” allegedly used to conceal the incidents, noting that a fifth were not reported to Colombian authorities.
A BBC investigation last year also found Ecopetrol has spilt oil hundreds of times since then.
Ecopetrol rejected claims that it has polluted local water sources, insisting it fully complies with Colombian law. But by the end of last year, huge swaths of the territory were still contaminated by a pipeline fracture, with an oily sheen coating the water and the air pungent with petrol.
Ecopetrol says its subsidiary is working to contain and remediate October’s leak, maintains that its operations comply with environmental regulations and have not harmed water quality, and highlights investments to cut discharges and protect wildlife.
The company also rejected the allegations contained in the Iguana Papers, insisting that incidents were duly reported, the data was misinterpreted and most historical contamination sites had already been restored.
Yet for riverside communities, which depend almost entirely on fishing for their livelihoods, the impact is clear. “Yet again, hundreds of fish, snakes, birds, turtles and caimans have died overnight,” says Luis Carlos Lambraño, 56, who has been fishing in these waters for 37 years.
“If we can’t fish, we can’t eat,” he says. “I feel utter sadness.”
Ronaldo Martínez, 68, who farms water buffalo, says the contamination has become impossible to ignore.
“The buffalo drink the water, get poisoned and die,” he says. “We’ve had about 30 buffalo die on us this way in the last five years.”
Martínez says that coming across a dead animal was unusual in the past. “It happened sometimes, but it wasn’t very common,” he says. “But lately, it’s become normal to find dead animals, dead caimans, dead fish.” He adds that when the fish are cut open during oil spills and suspected dumps, “they taste like oil”.
He says the responsibility lies with Ecopetrol. “[It] is our largest company,” he says. “They should have a way of managing their pools. Their oxidation ponds should be working.”
Compounding the crisis is the expansion of illegal armed groups that seek to rule the waterways. So-called “gasoline gangs” have moved into the area, which is considered a strategic corridor for moving illegal goods, hacking into the oil pipelines that crisscross through the waterways to steal and sell the fuel illicitly.
“Every single day they steal the gasoline,” says Velásquez, who, along with her colleagues, monitors biodiversity in the area. “They collect it in these massive plastic bags – when they break, which has happened at least twice, it spills into all of the water.”
The presence of armed groups has also made fishing perilous. Local activists say they have faced countless threats, intimidation campaigns and assassination attempts. Drones are used by armed groups to monitor and shadow fishing boats until they retreat.
Velásquez is one of the campaigners at risk. She says she has suffered repeated attacks on her home, three assassination attempts – one in which her bodyguard was shot – and many threats to her family for speaking up against the contamination and the armed groups.
The threats are taken very seriously as Colombia is one of the most dangerous countries worldwide for land and environmental defenders, according to Global Witness, accounting for a third of all documented lethal attacks.
“It has been devastating,” Velásquez says. After another fishing leader, Luis Arango, was assassinated in 2012, she says it “took a long time for people to raise their voices again”.
Lambraño describes an incident in February when he was intercepted by gang members and chased off the water. “They fired shots in the air, then followed me, shining their torch on me, until I left,” he says.
Eñi Salazar, who has fished these waters since she was seven, also has countless stories of being threatened for merely fishing. Armed men have twice intercepted her in the wetlands.
In one case, they seized her boat engine and threatened to kill her. In another, they opened fire during the fishing community’s ’s environmental monitoring activities, with bullets hitting an engine.
“They said to me: ‘We know who you are, we know your face, so if we ever see you here again, we’ll kill you’,” the 66-year-old says.
Amnesty International has reported a permanent atmosphere of harassment for fishing families in Barrancabermeja, recording extortion attempts, direct threats and people repeatedly forced to leave the area.
“Fishing families have felt the pressure from the armed groups for a long time, but in the last few years their presence has expanded,” says Alejandro Jiménez Ospina, a researcher on the Americas for Amnesty International.
“Oil smugglers, armed groups – everyone wants the water,” he says. “Whoever controls the water controls Barrancabermeja.”
Such intimidation forcibly displaced 26 fishing families in February 2025. “You don’t mess with the armed groups. If you don’t listen, they will kill you,” says Velásquez. She estimates that about 100 of her colleagues have stopped fishing.
But for Velásquez, waiting for action is no longer an option. “Every day we see places where wildlife used to live disappear,” she says. “We can’t wait for someone else to come and take care of it for us.”
What the community wants is simple, Velásquez says. “We want to be left alone to live in peace,” she says, “and to truly be able to enjoy our marsh, our river, day and night, without limits or restrictions telling us what time we can enter or what time we can leave, or where we can and can’t be.”
