Design and Construction

The proposed project would be constructed by the utilities and include the following components:

  • Approximately 95 miles of new double-circuit 230-kilovolt (kV) transmission line from the existing San Luis Valley Substation, north of Alamosa, to a new Calumet Substation near Walsenburg
  • A new 230/345-kV Calumet Substation at a location six miles north of Walsenburg on property owned by Tri-State and expansion of three existing substations
  • Approximately 45 miles of new double-circuit 345-kV transmission line between the proposed Calumet Substation and the existing Comanche Substation near Pueblo
  • Approximately six miles of new 230-kV transmission line between the proposed Calumet Substation and the existing Walsenburg Substation
  • Proposed communication facilities to support operation and maintenance of the transmission lines

Tri-State and Xcel Energy are proposing to use a combination of steel lattice structures and steel mono-poles. The choice of structure type would be based on location and design conditions (i.e. mountainous vs. flat terrain). The line would also use low corona hardware to minimize audible noise.

Construction would be completed in several phases: access development, staging structures, foundation construction, framing and erecting the structures, stringing conductor, clean up and reclamation. Several work phases may be in progress simultaneously at different locations along the alignment. Construction of the transmission line is expected to last approximately 18 to 24 months.

Engineering and Electric Transmission Fact Sheet
Details on how the proposed transmission line will be constructed


In the News

Power line generates public comments
Valley Courier
April 27, 2012


SLV power line headed back to drawing board
Pueblo Chieftain
April 27, 2012


Support for San Luis Valley line isn't powering down
Denver Post
November 2, 2011


Xcel is out, but transmission line is not
Valley Courier
November 2, 2011


Xcel likely to drop SLV solar, transmission line proposal
Pueblo Chieftain
November 1, 2011


San Luis Valley Power
Pueblo Chieftain
September 14, 2011


Colorado PUC reaffirms approval of San Luis Valley power line sought by Xcel, Tri-State
Denver Business Journal
September 2, 2011




This Web site is hosted and maintained by Tri-State and Xcel Energy. The goal is to provide Colorado residents with facts and details of transmission development as we work to provide safe, reliable electricity. We encourage and appreciate public input to the process.

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