American Transmission Co. (ATC) has begun construction on the Grid Forward - Central Wisconsin Project, with the project approximately 5% complete and remaining on schedule for its planned December 2030 in-service date.

ATC began transmission line construction in the second quarter of 2026 and recently installed the project’s first transmission structure, marking the transition from planning to active construction.

The Grid Forward - Central Wisconsin Project was approved as part of the Midcontinent Independent System Operator’s (MISO) Long Range Transmission Planning Tranche 1 portfolio. The project is designed to strengthen the regional electric transmission system, support long-term reliability and improve the grid’s ability to meet future energy needs across central Wisconsin and the broader Midwest.

“Grid Forward is an important investment in the region’s electric infrastructure and future reliability,” said Eric Lundberg, senior vice president of Asset Delivery. “Construction is underway, major milestones are being achieved and the project remains on track.”

Recent project accomplishments include:

• Installing the first transmission structure as the project moves into active construction.
• Advancing detailed engineering and design activities across multiple transmission line segments and substations.
• Continuing permitting and material procurement activities to support future construction work.
• Maintaining the planned December 2030 in-service date.

ATC also said the project is forecast to remain within the cost range approved by the Public Service Commission of Wisconsin and within approximately 2.5% of MISO’s original cost estimate when compared on a time value of money basis.

MISO’s original cost estimate was developed during the planning process and expressed in 2022 dollars. The current project forecast reflects additional years of inflation, refined engineering, project development activities and approved project modifications as the project advanced through regulatory review and into construction.

“As projects move from planning to construction, it is important that cost information be evaluated on a comparable basis and with appropriate context,” Lundberg said. “A simple comparison between an early planning-level cost estimate and a current construction forecast does not always tell the complete story.”

The project is also expected to provide long-term benefits for Wisconsin customers. Revenue requirement analysis prepared in support of the project estimates approximately $1.75 billion in net savings for Wisconsin customers over the life of the project. On a discounted basis, those savings are estimated at approximately $142 million.

The Grid Forward - Central Wisconsin Project includes rebuilding existing infrastructure and constructing new 345-kV transmission facilities to strengthen the regional transmission system, improve reliability and support Wisconsin’s growing energy needs.

More information about the project is available at ATC Grid Forward.