ATC narrows choices for Wisconsin portion of Bay Lake project

American Transmission Company (ATC) on April 10 said it has narrowed the possible route options for the Wisconsin portion of the Bay Lake transmission project, which includes 345-kV and 138-kV transmission lines in the area of Green Bay, Wis.

“We came up with a number of combinations of route segments that can be put together to get us from point ‘a’ to point ‘b,’” an ATC spokesperson told TransmissionHub April 11.

The company was able to narrow the route options after reevaluating project needs and determining it would not have to build a new substation in the Green Bay area as previously thought, and will instead be able to expand substation facilities at its existing North Appleton substation site.

Although ATC has reinforced its transmission facilities in the region over the past six years, the upgrades have not kept pace with the changing needs, according to the spokesperson, who added that reduced output from generating units at power plants in the area also has placed increasing importance on transmission. 

While the utility chose not to identify a preferred route for the transmission pathway due to the possible routing through developed areas where there is potential for congestion, such as in the area of Green Bay at the southern end of the line, the lines will extend from the North Appleton substation near Green Bay to the Morgan substation in Oconto County.

The company will hold open houses in early May in towns at each end of the line to present the proposed routes to residents and other stakeholders and to obtain their feedback about potential alignments.

Costs for the Wisconsin portion of the project range from $118m to $177m for the 345-kV portion of the project and from $71m to $106m for the 138-kV line. Those estimates include upgrades that will be necessary at the North Appleton substation, as well as a large voltage-control device that will be required and is likely to be located on ATC property near its Amberg, Wis., substation.

When the Bay Lake project was originally envisioned, it was divided into four project areas. However, work in the northernmost area, known as project area 3, was deferred when regional grid operator Midwest ISO (MISO) announced that it would be undertaking its Northern Area Study to address a number of transmission proposals and issues in the Canadian province of Manitoba, North Dakota, South Dakota, Minnesota, Wisconsin and Michigan.

At the end of 2012, ATC also deferred work on project area 2 when that area was subsumed into the MISO study, the spokesperson said.

In addition to the Green Bay area, which is known as project area 1, the other active project area is known as project area 4, which extends from the Holmes substation to the Escanaba substation in Michigan’s Upper Peninsula.

Total project costs are estimated at $118m to $177m for the 345-kV facilities and $155m to $232m for the 138-kV facilities. The company expects to start construction in 2015 with in-service dates from late 2016 to 2017, according to its project website.