Bridge Collapse Temporarily Halts Cameco Uranium Operation

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Written by Brian Ford, Editor-in-Chief for IIR News Intelligence and Loretta Clark, VP Research - North America Metals & Minerals (Sugar Land, Texas)

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Summary

Canadian uranium miner Cameco was forced to curb some of its production due to flooding and a bridge failure in Saskatchewan.

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Bridge Over Troubled Water

Uranium producer Cameco has temporarily idled its Key Lake Mill and reduced activity at its McArthur River Mine in Saskatchewan as a result of a bridge collapse in the region. The company's logistics problems may be coming to an end as transportation authorities said they were working to install a temporary emergency bridge by the end of May, according to news accounts.

The world's second-largest producer of uranium, Saskatoon-headquartered Cameco said on May 10 that flooding caused the collapse of the Smoothstone River Bridge, across which the miner moved supplies to the McArthur River and Key Lake sites. Flooding did not directly impact the Saskatchewan sites. Local restrictions prevented the use of an alternative roadway, it added. According to Industrial Info Resources data, there are four Cameco mining projects in Canada with a total investment value of US$1.68 billion.

"Depending on the duration of the road restrictions and our ability to make deliveries of critical operating materials, there is a risk that our 2026 production outlook for the McArthur River/Key Lake operation could be impacted," the company said.

According to Cameco's website, McArthur River is the world's largest high-grade uranium mine and Key Lake is the world's largest high-grade uranium mill. Ore slurry from McArthur River is trucked in special containers 80 kilometers (50 miles) to Key Lake where it's milled and blended for processing with low-grade ore stockpiled at the mill. Since 2000, the two operations have produced more than 580 million pounds of uranium concentrates.

The company's Cigar Lake uranium mine, also in Saskatchewan, was not impacted by the flooding or bridge failure. Subscribers to the Industrial Info Resources Global Market Intelligence (GMI) Metals & Minerals Plant Database can view detailed plant profiles of the McArthur River and Cigar Lake mines.

Saskatchewan's Ministry of Highways has brought in a contractor to build a temporary crossing over the Smoothstone River, with the goal of completing the job by the end of May, according to Saskatoon radio station CKOM.

Guidance for 2026

Cameco's 2026 guidance currently calls for 14.0 million-6.5 million pounds of uranium production from the McArthur River and Key Lake operations, with its attributable share expected to be between 10.0 million and 11.5 million pounds.

At the Cigar Lake mine, total production is projected between 17.5 million and 18.0 million pounds, with Cameco's share estimated at 9.5 million-10.0 million pounds. Cigar Lake is owned by Cameco, Orano Canada and Tokyo Electric Power Company in a joint venture. Cameco has a majority share at 54.547% and is the operator.

In addition to its Canadian holdings, Cameco also has a 40% stake in the Inkai joint venture uranium ore mine in Kazakhstan and owns a 49% stake in Westinghouse Electric Company, a major provider of nuclear technology and equipment.

In reporting Cameco's first-quarter earnings results on May 5, Chief Executive Officer Tim Gitzel said, "Operationally, we delivered solid performance in the quarter, with on-track production at our uranium mining operations in Canada and Kazakhstan. We're in a strong position ahead of the extended third-quarter maintenance shutdown at the Key Lake mill that we mentioned at the beginning of the year, during which we will tie in new infrastructure to enhance future supply flexibility."

The annual shutdown of the Key Lake Mill in the third quarter will include the installation of new infrastructure and repairs to major existing infrastructure. As a result of this work, the shutdown is expected to be longer than in previous years.

Cameco reported C$131 million (US$95 million) in first-quarter earnings, up from C$70 million (US$51 million) in first-quarter 2025. First-quarter sales volumes were higher in both uranium and fuel services.

Key Takeaways

• Uranium miner Cameco temporarily idled its Key Lake Mill and reduced activity at its McArthur River Mine in Saskatchewan as a result of a bridge collapse.
• The company may be forced to lower its 2026 production outlook.
• The installation of a temporary emergency bridge is expected by the end of May.

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Industrial Info Resources (IIR) is the leading provider of industrial market intelligence. Since 1983, IIR has provided comprehensive research, news and analysis on the industrial process, manufacturing and energy related industries. IIR's Global Market Intelligence (GMI) helps companies identify and pursue trends across multiple markets with access to real, qualified and validated plant and project opportunities. Across the world, Industrial Info Resources is tracking over 250,000 current and future projects worth $30.2 Trillion (USD).