Mill Road – Granville Project

ATC plans to build a new substation in the village of Menomonee Falls, construct a new power line from Menomonee Falls to Wauwatosa, and rebuild and upgrade several existing lines in portions of Milwaukee, Washington and Waukesha counties.

The key elements of the project include:

  • Building a new substation on property ATC currently owns in the village of Menomonee Falls near Mill and Marcy Roads.  
  • Constructing a new 138,000-volt power line from the proposed Mill Road Substation to the existing Butler Substation in Wauwatosa. We are proposing two route alternatives for this new line. 
  • Rebuilding power lines running from the proposed Mill Road Substation to an existing substation along 76th Street in Milwaukee. We are proposing to upgrade the voltage on one of the lines from 138-kV to 345-kV. During construction, a temporary 138-kV line would be installed on the south side of our existing lines for approximately one mile from the Mill Road Substation to the existing substation easy of Marcy Road. 
  • Replacing conductor wires on the existing power lines running north from the proposed Mill Road Substation to an existing substation in the village of Germantown. Certain structures (poles) would also be replaced. 
  • Make some upgrades to the line running south of the proposed Mill Road Substation south to an existing substation in New Berlin. Some structures (poles) may be replaced to bring the power line up to standards. 

The project is estimated to cost approximately $400 million.

The project is needed to maintain reliability and support local energy demand and is subject to approval by the Public Service Commission of Wisconsin. Additional information about the proposed project can be found on the Public Service Commission of Wisconsin website, under docket number 137-CE-212.

Project Video

Milestones

Fall 2024
Late 2025
Summer 2026
2028
Fall 2024
*Dates are anticipated and subject to changes
Late 2025
*Dates are anticipated and subject to changes
Summer 2026
*Dates are anticipated and subject to changes
2028
*Dates are anticipated and subject to changes

Project FAQ's

A:

The project is needed to maintain reliability and support local energy demand.

A:

ATC is proposing to construct a new 138-kV power line from the proposed Mill Road Substation to the existing Butler Substation in Wauwatosa. We are required to propose two route alternatives for this new line. The Public Service Commission of Wisconsin is the regulatory agency with the authority to approve or deny major utility projects in Wisconsin. In this case, ATC will propose two routes and, if the power line project is approved, the PSCW will select the final route.

A:

We anticipate the cost of the projects will be approximately $400 million. The cost of the project would be shared by all ATC customers.