MediumVI Energy Politics & Supply Security8 October 2026, Thursday
Illegal miners in Congo threaten water supply to the Nzilo hydropower plant
Illegal miners occupying ERG's Metalkol site in Kolwezi have blocked a water drainage structure. The company warned that water flowing to the reservoirs of the 100 MW Nzilo plant could decline.
Ecofin reported on 8 October, citing an internal note reviewed by its sister publication Bankable, that the group holding part of the Metalkol site in Lualaba province blocked a drainage structure to protect its own area from flooding. The move could divert water in the Musonoi river basin towards the Kasubantu dam and reduce the flow feeding the reservoirs of the Nzilo plant, which has an installed capacity of around 100 MW. Metalkol said it had informed SNEL, the national power utility, and would send a formal notice. According to the company, copper and cobalt output has not yet fallen.
The occupation began in February 2026, was partly cleared by the army in May and resumed in August. Miningmx, citing Bloomberg on 9 September, reported ERG as saying that armed men in uniform were present during the new occupation that began on 21 August, and that some 700 tonnes of tailings a day were being moved to nearby Chinese-owned facilities. Ecofin's local sources say about 50 trucks of 50 tonnes each leave the site daily; that equals 2,500 tonnes a day, more than three times ERG's figure. Neither number could be independently verified.
The constraint is that mining in Congo's copper belt depends on electricity, and through plants such as the 100 MW Nzilo, electricity depends on water. Metalkol's nameplate capacity is about 100,000 tonnes of copper and 23,000 tonnes of cobalt a year, making it one of the country's largest cobalt export suppliers after CMOC and Glencore. President Félix Tshisekedi ordered an end to illegal armed activity at mining sites in July; the return in August shows the order has not been enforced on the ground.
Talay assessment
Bottom line
The Metalkol episode shows that supply risk in Congo's copper belt is no longer just about cobalt quotas but about the security of water and power infrastructure. The armed-backed occupation persists despite July's presidential order. Nzilo's 100 MW alone would not black out the region, but disrupted flows in the rainy season could cut the plant's output. The most likely path is a drawn-out legal and military standoff with no loss of production.
Likely effects
- Copper belt powerNegative1–6 months
According to Ecofin, the 100 MW Nzilo plant supports power supply to the mining region; if its water falls, the risk of outages at mines around Kolwezi grows.
- Cobalt supplyNegative1–6 months
Tailings from a plant with 23,000 tonnes of annual capacity moving through informal channels to Chinese-owned facilities creates untraceable supply despite the quota system.
- Investment riskNegative6 months+
Two occupations in six months, both allegedly with military backing, raise the legal security premium for foreign miners in Congo.
Possibilities, ranked
- 1Drawn-out standoff, output continues55%
The occupation persists and Metalkol and SNEL pursue formal channels, but copper and cobalt output and Nzilo's generation do not fall markedly.
Watch: Metalkol's formal notice to SNEL and a statement from the Inspectorate General of Mines
- 2The state clears the site25%
The army clears the site as it did in May and the drainage structure is reopened.
Watch: Reports of a military operation in Lualaba and ERG confirming access to the site
- 3Power cuts20%
Flows are disrupted in the rainy season, Nzilo's output falls and outages begin at mines in the region.
Watch: A SNEL load-shedding or outage notice for the Kolwezi area
Probabilities are calibrated judgement based on the sources, not measurement, and are revised as new information arrives. Not investment advice.
Market reaction
Indicators affected
- Nzilo installed capacity▼ ~100 MW
- Metalkol cobalt capacity▼ 23kt/yr