Otter Tail Power Company and WMMPA Receive MN Route Permit Approval for New Transmission Line

Fergus Falls, MN – On June 25, Otter Tail Power Company and Western Minnesota Municipal Power Agency (WMMPA), represented through its agent Missouri River Energy Services (MRES), received the written order from the Minnesota Public Utilities Commission (MPUC) approving a Route Permit for the Big Stone South to Alexandria (BSSA) 345-kilovolt transmission line. The utilities will co-own the approximately 96-mile transmission line, strengthening the regional grid and supporting reliable, cost-effective electricity.

BSSA will connect Otter Tail Power’s existing substation near Big Stone City, South Dakota, with MRES’s existing substation near Alexandria, Minnesota. The companies filed the Route Permit application for the Minnesota portion of the line with the MPUC on October 22, 2024.

“This is a significant milestone as new infrastructure takes years to plan, permit, and build, and we appreciate the Commission’s approval of the Route Permit,” said the companies. “Reliability isn’t built through engineering alone. It’s built through accountability, experience, and a proven track record of keeping people informed, respecting landowners, and working through a transparent, regulated process. This investment helps us continue to meet growing energy needs while maintaining a reliable, resilient energy grid for our customers and the region.”

Otter Tail Power and WMMPA received a Certificate of Need from the MPUC in October 2024, confirming the line is necessary and appropriately sized, timed, and designed. In January 2025, the South Dakota Public Utilities Commission approved a Facility Permit for the approximately 3.5-mile portion in South Dakota.

Right-of-way agents will work with landowners along the approved route to establish easements and determine structure locations. The companies anticipate construction to begin in 2028 and are targeting an in-service date by the end of 2030. For more information about BSSA, visit BigStoneSouthToAlexandria.com.

Story courtesy of Otter Tail Power Company.