After more than five years of public involvement and regulatory review, the Public Service Commission of Wisconsin approved a vital addition to Dane County’s electric transmission system to be constructed by American Transmision Co. This project will serve multiple reliability functions and involves constructing approximately 32 mi of new 345-kV transmission line to connect the existing Rockdale Substation located near the Town of Christiana with the West Middleton Substation in the town of Middleton. The substations will require some equipment upgrades to support this new line.

Dane County has experienced in recent years some of the highest growth rates in the state, both in population and electricity usage. The existing transmission system in and around Dane County brings power in from outside the county to meet the needs for electricity.

However, the system is operating at its limits and additional transmission lines are needed to keep pace with the growing dximetely $215 million.emand, and to strengthen the efficiency and reliability of existing lower voltage lines. The line will be constructed on steel poles at a cost of approximately $215 million.

Currently the work underway involves doing test soil borings for the transmission structure foundations. It’s a pretty safe bet in Wisconsin that the ground is frozen in January. That makes it an ideal time to conduct these soil boring, a necessary step in designing transmission lines. Taking advantage of frozen conditions minimizes environmental impacts. To that end, this month ATC ed drilling small (2- to 3-in diameter) bores at depths of up to 40 ft along the 32-mi route for the Rockdale-West Middleton project.