During the spring and summer of 1997, interruptible customer load was shed several times, but firm service was not interrupted. Unique circumstances caused numerous nuclear power plants in Wisconsin and Illinois to be out of service. Bringing in unusually large quantities of power from outside stressed the transmission system, which was never designed to handle such conditions. The situation prompted concern regarding the lack of generation and transmission and its effect on electric service. That concern was elevated on June 11, 1997, with the outage of a key east-west transmission line – known as King-Eau Claire – affected the reliability of service to electric customers in the region.

On June 25, 1998, several Midwestern states and Canadian provinces came close to a large-scale, regional blackout. This severe disturbance knocked out electric power to a number of industrial customers throughout Northeastern Minnesota and all customers in Northwestern Ontario. If not for extraordinary operating measures, all of Minnesota, Wisconsin, North Dakota, South Dakota, Manitoba and Ontario would have gone dark.

Wisconsin and Minnesota companies joined together to propose the Arrowhead-Weston Transmission Line project.