American Transmission Co. projects

Project website for a Wisconsin-based company that owns and operates the high-voltage electric transmission system that powers communities in portions of the Upper Midwest.

Project overview

Samples of what the poles may look like for this project.

Examples of what the poles may look like for this project.

ATC has identified an electric reliability issue that puts southeast Wisconsin and northeast Illinois at risk for a cascading transmission system outage under certain operating conditions, including high power flows from Wisconsin to Illinois. ATC is proposing a cost-effective solution which provides an alternative power path to address emergency conditions and accommodate increased power flows. Components of the project include:

  • Constructing a double-circuit 345-kilovolt transmission line that would electrically connect to an existing line near Pleasant Prairie, Wis.
  • Connecting the new transmission line to the ComEd transmission system through a proposed new substation on the north side of Rosecrans Road (Hwy. 173) in the Village of Wadsworth, Ill.

Depending on the route selected, the transmission line could range from three to five miles in length. This project requires approvals from the Illinois Commerce Commission and the Public Service Commission of Wisconsin. The estimated cost of the project could range from $55 million to $66 million.

Project need and benefits

The existing transmission system cannot adequately support the growing north-south electrical flows in this specific region. ATC is proposing this project to mitigate the potential risk of cascading outages and a widespread, regional blackout.

  • A new 345-kV connection between Wisconsin and Illinois will provide an alternative path to respond to the risk of overloading existing lines and to provide some operational flexibility.
  • This new electrical connection will create economic benefits by providing utilities with access to the regional wholesale electricity market, where they can buy and sell power when it’s economic to do so for the benefit of their customers.
Project at a glance 
Areas benefited: Southeastern Wisconsin, northeastern Illinois and the Midwest region
Line length: 3 to 5 miles
Voltage: 345,000 volts
Estimated cost: $55 million to $66 million
End points: On the north end – a tie-in to an existing, east-west transmission line along County Trunk Highway H near the Village of Pleasant Prairie; on the south end – a connection to the ComEd system through a proposed substation in the Village of Wadsworth, IL
Project schedule 
Project introduced to the publicEarly spring 2016
Finalize route alternativesSpring 2016
Submit application to the Illinois Commerce Commission Summer 2016
Decision received from the ICC
December 2016
Submit application to the Public Service Commission of WisconsinJanuary 2017
Anticipated decision from the PSCWFall 2018
Start constructionSpring 2020
In-service date2021