ATC: Detailed design of transmission line assets for 138-kV rebuild will be completed by end of May

American Transmission Company recently provided an update on its St. Martins-Edgewood-Mukwonago Rebuild Project to Wisconsin regulators, noting that transmission line design continues with preliminary foundation design and evaluation of different construction installation techniques – direct-embed versus vibratory caisson – based on soil quality from soil boring reports.

As TransmissionHub reported, ATC’s request for a one-year extension to begin construction on rebuilding existing 138-kV electric transmission line and substation facilities between the existing St. Martins and Edgewood substations, and between the Edgewood and Mukwonago substations, was granted last year.   

According to a Nov. 15, 2016, filing by the state Division of Energy Regulation, the Public Service Commission (PSC) of Wisconsin in October 2015 approved ATC’s application for authority to rebuild the existing 138-kV lines. Order Condition 15 in the final decision stated that “if ATC does not begin on-site physical construction within one year of the effective date of this certificate of authority and order, the certificate authorizing the approved project shall become void unless ATC: files a written request for an extension of time with the commission before the date on which the certificate becomes void, and is granted an extension by the commission.”

ATC in August 2016 filed a written request for extension to begin construction for the approved project, the division said, adding that the company’s stated reasons for its request were “resource constraints, primarily the availability of construction labor.”

ATC requested an extension of one year, until September 2018, in order to begin construction, the division said.

In its Jan. 24 quarterly progress report for the period Oct. 1, 2016, through Dec. 31, 2016, filed with the PSC, ATC said that these transmission line design activities have been completed:

  • Finalized transmission line foundation types for use with loading drawings
  • Issued steel pole loading drawings and exhibits for comment
  • Issued assembly and structure detail drawings for comment
  • Started preparation of transmission line construction specification

ATC also said that detailed design continues on the St. Martins substation, and that these substation design activities have been completed:

  • Issued preliminary electrical and physical designs for comment
  • Ordered long-lead time equipment

ATC said that detailed design of the transmission line assets will be completed by the end of May, while detailed design of the substation assets will be completed by the end of March 2018.

Construction is scheduled to begin in 2018, and be completed by June 2019, the company said.

ATC also noted that the Wisconsin Department of Natural Resources utility permit was received last October, and that a permit from the U.S. Army Corps of Engineers has not yet been issued.

The company noted that of the approved total project costs of about $24.7m, actual project costs as of Dec. 31, 2016, were about $1.6m.

About Corina Rivera-Linares 3286 Articles
Corina Rivera-Linares was TransmissionHub’s chief editor until August 2021, as well as part of the team that established TransmissionHub in 2011. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial from 2005 to 2011. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines.