The fate of a high-voltage electric transmission line designed to supply the Upper Midwest with cheap wind power has been thrown into doubt after a federal judge in Wisconsin ruled that a proposed river crossing is incompatible with a national wildlife refuge.

The approximately 100-mile, 345-kV Cardinal-Hickory Creek transmission line — developed jointly by American Transmission Co. LLC, ITC Holdings Corp. subsidiary ITC Midwest LLC and Dairyland Power Cooperative — is already under construction between Dubuque County, Iowa, and Dane County, Wis.

But U.S. District Court Judge William Conley issued a preliminary injunction for the project on Jan. 14, finding the U.S. Fish and Wildlife Service's acknowledgment that the $492 million project goes beyond maintenance places a proposed river crossing at odds with the express purpose of the Upper Mississippi River National Wildlife and Fish Refuge.

The ruling handed a victory to a coalition of conservation groups led by the National Wildlife Refuge Association, which opposed the proposed river crossing on environmental grounds.

In December 2019, the Fish and Wildlife Service found that the Cardinal-Hickory Creek line was compatible with the refuge as "a minor realignment of an existing right-of-way" and granted a permit for the project. But the agency revoked that determination in August 2021 after the utility developers proposed to exchange a 30-acre parcel in the refuge instead of seeking an amended right-of-way.

Since then, the Fish and Wildlife Service has made "no attempt" to argue that the Cardinal-Hickory Creek line would be a minor realignment, Conley noted in a Jan. 14 opinion.

And the utilities' new proposed land acquisition would impact 39 acres, with less than 9 acres overlapping their existing rights of way, the judge said.

Conley, therefore, found that the Cardinal-Hickory Creek line cannot be considered minor under the National Wildlife Refuge System Improvement Act of 1997.

"Now that Fish and Wildlife has acknowledged that the [Cardinal-Hickory Creek] project is not maintenance, however, compensatory mitigation is categorically disallowed as a reason for compatibility, taking away the one defense the utilities had to the obvious incompatibility of the [Cardinal-Hickory Creek] project with the refuge's express purposes," Conley wrote. "Given these direct contradictions, therefore, the [Cardinal-Hickory Creek] project's proposed crossing cannot be deemed compatible with the refuge. Any Fish and Wildlife decision to the contrary would be arbitrary and capricious."

Conley's Jan. 14 opinion invited parties in the case — National Wildlife Refuge Association et al. v. American Transmission Company LLC et al. (No. 21-cv-096-wmc) — to file additional briefs by Jan. 24 suggesting appropriate language for a final judgment.

Developers maintain commitment to project

In a Jan. 18 statement, American Transmission, ITC Midwest and Dairyland Power said they are still committed to completing the project.

The companies maintained that the Jan. 14 preliminary injunction "has no immediate impact on the co-owners' ability to continue construction activities" pursuant to a November 2021 injunction barring new construction within the refuge.

The Cardinal-Hickory Creek line "will reduce energy costs, improve electric grid reliability, relieve congestion on the transmission system, support decarbonization goals and help support the interconnection of renewable generation in the Upper Midwest," the utilities said.

The line, originally due to be completed by the end of 2023, is one of the Midcontinent ISO's "multivalue projects," designated as benefitting the region's overall reliability and providing access to new wind resources.

Wisconsin utility regulators granted the project a certificate of public convenience and necessity in September 2019, and Iowa regulators gave their approval in May 2020.