1. Skip to content
  2. Skip to main menu
  3. Skip to more DW sites

Gold, greed, poison: How miners pollute Mozambique's rivers

September 16, 2025

In the Mozambican province of Manica, illegal gold miners are causing environmental damage while posing a serious threat to human and animal life. Environmentalists and government authorities are sounding the alarm.

Illegal miners in Mozambique's Manica region
Uncontrolled gold mining is causing severe damage to the ecosystem in Manica, western MozambiqueImage: DW

Thousands of so-called 'garimpeiros' are flocking to the gold-rich region along the Revue River and its tributaries in western Mozambique. These illegal gold miners hail not only from across Mozambique but also from neighboring countries such as Zimbabwe, Malawi and Zambia.

Driven by hope for a better life, they pay little attention to environmental protections and related concerns, as they employ toxic chemicals such as mercury, cyanide and arsenic to extract gold from rock and sediment.

These highly poisonous substances seep into the soil and water during the mining process with devastating consequences for ecosystems and local communities.

The Chicamba Dam, the region's most important source of drinking water, and the Revue River are particularly affected by this pollution.

Francisca Tomas, Governor of Manica, calls for sustainable mining practices with regular inspectionsImage: DW

Provincial government promises to take tougher action

The provincial government of Manica, which lies in central Mozambique and borders Zimbabwe, has announced plans to stop informal mining and crack down harder on the garimpeiros; even licensed mining operations will be subject to stricter oversight in response to the growing crisis.

International companies like Xtract Resources plc and Horizonte Minerals plc, both headquartered in the UK, claim to fully comply with environmental standards.

Having held gold mining concessions in Manica for years, they also stress that they pay taxes locally, unlike the informal miners. Still, these companies are also set to undergo a review.

At a press briefing in early September, Manica governor Francisca Tomas emphasized that environmental protection was her main concern:

"We must keep our rivers clean and flowing — not just for agriculture but for the people who depend on them for drinking water."

Mercury, cyanide, arsenic: Polluted rivers pose serious health risks to the local population in Manica ProvinceImage: DW

Illegal mining practices on the rise

The Manica District is home to some of Mozambique's richest gold reserves and has become the epicenter of small-scale mining. But many miners continue to operate outside legal frameworks, disregarding existing environmental laws.

The result is that riverbeds are drying up, the water is turning murky and many areas are increasingly being blocked with silt. This is partly due to weak state regulations and a lack of overall environmental monitoring.

Governor Tomas is calling for regular inspections and a sustainable regulation of gold mining to ensure that natural resources can be used in a way that balances human needs and environmental protection.

But in areas like Mukurumadzi and Penhalonga, where several smaller rivers flow into the Revue, the conditions have worsened dramatically in recent months despite government attempts to intervene.

One illegal miner, Leonardo Beissicopo, openly describes how his method ignores basic environmental concerns:

"First we grind the sand, then we use carpets to catch the gold. After that, we add mercury to bind the gold. And the wastewater flows straight into the rivers," he said, mentioning also the casual use of heavy machinery, drills, generators, compressors and even explosives in the process.

"We have no other choice but to keep mining," say the garimpeiros, struggling to feed themselves and their familiesImage: DW

Another miner, Veloso Elias, meanwhile says that he is aware of the risks but has no other choice:

"We know mercury is harmful to people and animals, but we have no other way to extract the gold.”

A call to leaders to intervene

In an effort to curb unregulated mining, Governor Tomas is now proactively seeking support from traditional and religious leaders in the district.

She says their role is to help raise awareness and ensure compliance with new regulations, while working "together to control the miners and reduce environmental damage."

"We're facing a serious problem. The rivers are polluted, some have already dried up, and the Chicamba Dam is heavily silted," Tomas further explained. 

Environmental activist Bernardo Xavier fights against illegal gold mining practices, while acknowledging that raising awareness is an uphill battleImage: DW

Environmental activist Bernardo Xavier meanwhile warns of dire health consequences if leaders fail to intervene:

"Our rivers are highly contaminated with heavy metals, yet many people have no choice but to drink the water," Xavier stresses.

He is calling for the strict enforcement of ecological standards in the mining sector to safeguard long-term water quality.

But raising awareness among the miners is a difficult task, as most of them live in poverty.

"Their main priority is feeding their families. When authorities crack down, they disappear for a while — but then they always return. Many come from outside the country, which makes law enforcement even more difficult," says Xavier.

Thousands of gold miners, many entering from neighboring Zimbabwe, continue to flock to Mozambique's Manica province despite harsher penaltiesImage: DW

Edited by: Sertan Sanderson

Skip next section Explore more
Skip next section DW's Top Story

DW's Top Story

Skip next section More stories from DW