A joint venture of American Transmission Company, ITC Midwest and Dairyland Power Cooperative, the Cardinal-Hickory Creek line would stretch across more than 100 miles of the Driftless area.  The $500 million costs -- and any possible benefits -- would be shared by ratepayers in 12 states. Wisconsin’s share is about $70 million.

Utilities and some environmental groups say it would deliver cheap, clean wind energy from Iowa, saving ratepayers money. Opponents question the public value, saying it would enable little new wind energy and damage important conservation areas.