Cameco had announced that the Key Lake mill and McArthur River mine have returned to full production activities following a disruption caused by flooding in northern Saskatchewan. On May 10, 2026, Cameco announced that Key Lake had temporarily halted production activities and McArthur River had reduced activities due to the impact of flooding in northern Saskatchewan. While northern Saskatchewan sites were not directly impacted by flood waters, the Smoothstone River Bridge, which is on the primary route used to transport supplies to the McArthur River and Key Lake sites, partially collapsed due to flood waters.

There were also weight and traffic restrictions on the alternative roadway, which interrupted the delivery of critical operating materials. Cameco is in regular contact with the Saskatchewan Ministry of Highways, and while the timing to restore access to the primary supply route is still being confirmed, Cameco has now been able to consistently deliver the volume of critical materials required to resume full operations at Key Lake and McArthur River using the secondary route. However, as is the case every spring season, there remains a risk that continued thawing and precipitation events could result in further road restrictions, which could cause delays in future deliveries of critical operating materials to the sites.

The 2026 production plan for the McArthur River/Key Lake operation has not been impacted by this disruption. Cigar Lake mine was not impacted and continues to operate.