The three utility companies that want to build a high-powered transmission line from Middleton to Iowa submitted an application to the Public Service Commission of Wisconsin on Friday.
American Transmission, ITC Midwest and Dairyland Power Cooperative want to build a 345-kilovolt transmission line from Middleton’s Cardinal Substation to Dubuque, Iowa, according to the group’s filing.
The application is the first step in the regulatory approval process. The Cardinal-Hickory Creek Transmission Line project will also need to be approved by other state and federal agencies.
The companies have chosen two routes — a preferred one and an alternate — that would stretch between 87 and 102 miles from the Cardinal Substation southwest to Dubuque.
Depending on the route that is selected, the project is estimated to cost between $492 million and $543 million, according to the application. Wisconsin customers would pay between $66 million and $72 million.
If approved, the utility companies say the line would lower wholesale energy costs and increase access to wind power, according to the application.
The companies say the project could provide Wisconsin customers with “net economic benefits” of between $23.5 million and $350 million over its expected 40-year life.
“The Project will provide substantial net economic, reliability and public policy benefits to Wisconsin, Iowa, and the region,” the companies said in the application. “It will also provide much-needed flexibility for the regional transmission system to respond to the ever-changing energy markets.”
But critics of the proposal say the project would be harmful to important conservation areas that it would be built on.
The project would cross Wisconsin’s Driftless area and go through the Upper Mississippi River National Wildlife and Fish Refuge and several wildlife and conservation areas.
Thomas Content, executive director of the Citizens Utility Board, said the group has a number of questions about the project, including whether it is necessary and if it will benefit customers in Wisconsin, now that the application has been filed.
“We want key questions answered,” he said. “At a time when we’re witnessing rapidly evolving technologies, have the utilities proposing the line considered alternatives to a big high-voltage line to meet the power needs of Wisconsin?”
If approved, the utility companies hope to have the project operational in 2023.