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.

After more than five years of public involvement and regulatory review, the Public Service Commission of Wisconsin approved a vital addition to Dane County’s electric transmission system in June 2009. This project serves multiple reliability functions and involved constructing 32 miles of new 345-kilovolt transmission line connecting the existing Rockdale Substation located near the Town of Christiana with the West Middleton Substation.

The line was placed in service in February 2013.

Dane County has experienced in recent years some of the highest growth rates in the state, both in population and electricity usage. The existing transmission system in and around Dane County brings power from outside of the county to meet electric demand.

However, the system is operating at its limits and additional transmission lines are needed to keep pace with the growing demand, and to strengthen the efficiency and reliability of existing lower voltage lines.

Project at a Glance
Communities affected:The towns of Christiana, Middleton, City of Madison and several communities along the route; all of Dane County and southern Wisconsin will benefit from this project.
Line length:Approximately 32 miles
Voltage:345,000 volts
Estimated final cost:Approximately $152 million
(final costs are still being calculated)
End points:The West Middleton Substation in the Town of Middleton and the Rockdale Substation near Christiana
PSC Project
Docket ID:
137-CE-147 Visit the PSC website
Project status:Completed and in service
Public open houses:July 2005-Aug. 2007
Announcement of final route options:Aug. 2007
Application submitted to Public Service Commission:October 2007
Regulatory review:Oct. 2007-June 2009
Technical and public hearings at PSC office:March 2009
Received PSC decision:June 2009
Began construction:2011
Project in service:February 2013