According to the company, upgrading this 74-mile line from 69,000 volts to 138,000 volts has helped reinforce the electric system in the entire region.

ATC proposed the project in 2004 and it was approved by the Public Service Commission of Wisconsin in 2006 at an authorized cost of $118m. The project also included a new 16-mile, 115kV line between Eagle River and Conover, which was placed in service in June 2008.

Rebuilding the lines between Conover and Quinnesec began in 2009 and was completed more than two months ahead of schedule. The project also involved construction of two new substations and modifications or upgrades to six additional substations, the company said.

ATC owns, operates, builds and maintains the high-voltage electric transmission system serving portions of Wisconsin, Michigan, Minnesota and Illinois.