The Zambian government has ordered a copper miner to assess its infrastructure for weaknesses and clean up areas affected by pollution of the Kafue River, after residents downstream of the plant that processes the mine’s waste reported changes in the river’s color, taste, and smell on Sept. 28.
The order also requires Konkola Copper Mines (KCM) to cover laboratory testing and related costs.
The pollution was traced to a leaking pipe at KCM’s tailings leach plant and an overflow from a pollution control dam on the Mushishima Stream, a tributary of the Kafue. The company disputes allegations that it caused the pollution, saying it detected the river’s discoloration and reported the incident to local authorities.
The incident has renewed concerns about recurring pollution in the Kafue, which Misozi Ngulube, director-general of Zambia’s Water Resources Management Authority (WARMA), has described as the country’s most polluted water body.
In February 2025, the breach of a tailings dam operated by Sino-Metals Leach Zambia, also on the Kafue, released more than 50 million liters (13 million gallons) of toxic sludge into a tributary. The spill killed fish more than 100 kilometers (60 miles) downstream, damaged crops, and disrupted local water supplies. The government reported three cases of minor illness, but the event raised broader concerns for communities and wildlife.
Ngulube told Mongabay that pollution in the Kafue comes largely from agriculture, industry, and mining.
She said WARMA has acquired a water-quality monitoring system and is working toward real-time pollution detection.
However, monitoring alone can’t prevent spills. Maggie Mwape, executive director of the Centre for Environment Justice (CEJ), said the challenge is to ensure infrastructure is monitored closely enough for failures to be detected and stopped before pollution reaches the river.
“Halting effluent discharge is critical to preventing further environmental damage, while transparent assessments of pollution control dams, tailings pipelines and related infrastructure are needed,” Mwape told Mongabay in a statement. “Weekly water quality monitoring should continue until the Mushishima Stream and Kafue River are confirmed safe.”
She also called for independent verification and publication of heavy-metal test results.
For local communities along the river, each incident carries a cost beyond the color of the water.
“I fear for my son, I don’t know what next will happen,” Mary Chunga, a resident of Shimulala, a community along the Mushishima, told Mongabay. “This water here is unsafe because of the recurring pollution from the mines upstream.”
Another resident, Godwin Simasiku, questioned the viability of farming after repeated pollution.
“Until monitoring and enforcement get ahead of pollution, rather than responding after the damage is done, the question will remain: how many more warnings must the Kafue give before action is taken?” Simasiku told Mongabay. “It is heartbreaking to witness the repeated pollution of the Mushishima Stream and the devastating effects it continues to have.”
Banner image: Last year’s pollution on the Mushishima stream. Image courtesy of Chisapi Kumbutso.
