Operations at a major Chinese-owned copper and cobalt mine in the Democratic Republic of Congo (DR Congo) have been suspended after a dam collapse released contaminated water into Lubumbashi, the country’s second-largest city home to over 3 million residents.
A containment dam belonging to Congo Dongfang International Mining (CDM), a subsidiary of Zhejiang Huayou Cobalt Co based in Tongxiang, Zhejiang province, China, continues to leave a trail of devastation across Lubumbashi’s ecosystem after releasing “several million cubic meters of electrolytes” since November 4.
The spill flooded hundreds of homes across three neighborhoods, forcing residents to flee, while environmentalists warn it could contaminate local well water, a vital daily resource for many households.
Growing Environmental Concerns in the Copperbelt
The incident is the latest environmental crisis in the Copperbelt region, which spans DR Congo and Zambia. Earlier this year, a Chinese-owned dam in Zambia collapsed, releasing cyanide- and arsenic-laden waste into the Kafue River, a critical water source for millions.
The spill occurred in February at the Sino-Metals Leach Zambia copper mine, a subsidiary of the state-run China Nonferrous Metal Mining Group.
An environmental cleanup company, Drizit, said its two-month investigation found the dam released 1.5 million tons of toxic material, at least 30 times more than the company initially admitted.
Drizit also reported that Sino-Metals terminated its contract one day before the final report was due, despite being informed of the severity of the pollution.
Authorities and Experts Criticize Safety Standards
In DR Congo, the country’s Mines Minister Louis Watum criticized CDM’s explanation of the spill, saying the company’s waste storage and processing facilities “do not meet any international standards.” Watum pointed to a lack of watertight barriers, structural stability, control devices, and emergency plans.
Early assessments by environmental experts indicate serious ecological damage. According to the OCC, a government-commissioned group of independent researchers, water in the affected region is heavily contaminated with lead, arsenic, and other toxins.
“We are already seeing biodiversity loss, especially fish and insects,” said Dickson Kabange, a member of the commission, after sampling the Lubumbashi River.
Experts also warn of potential health impacts for the city’s more than 3 million residents.
“Some people will inhale toxic substances evaporating from the river,” Kabange said. “Fish poisoned by the spill could also reach local markets, endangering thousands.”
Calls for Greater Oversight
DR Congo, the world’s largest producer of cobalt—a key mineral for electric vehicle batteries and other green energy technologies, is reportedly planning to engage with the United States later this month or next for a deal.
Meanwhile, Chinese-owned CDM generated $1.1 billion in revenue in 2024, down from $1.52 billion in 2023, largely from copper exports, according to the country’s mining ministry.
The Lubumbashi spill comes amid a broader pattern of environmental incidents involving Chinese-owned mining operations in the region, including the Sino-Metals Leach Zambia disaster earlier this year.
These events have intensified calls from African governments and environmental groups for stricter safety standards, transparency, and accountability in the sector.
