AZ Power -- Planning for Arizona's Future

Desert Basin power line project

SRP completed the process of siting a new 230-kilovolt (230kV) transmission line from the Desert Basin Generating Station to the permitted PW-SEV/BRG 500/230kV corridor. The 230kV line will continue to the Pinal Central (formerly Pinal South) substation to be located east of Casa Grande, near Eleven Mile Corner Road.

ACC approves CEC

On June 5, 2007, the Arizona Corporation Commission (ACC) approved the Siting Committee's recommendation for a Certificate of Environmental Compatibility (CEC) for the Desert Basin 230kV project by a 50 vote.

View a map of the approved alignment. (191K PDF)

View the CEC (5.4MB PDF) and a color version of Exhibit B (102K PDF).

CEC recommendation

The Arizona Power Plant and Transmission Line Siting Committee recommended a Certificate of Environmental Compatibility (CEC) for the project.

View the CEC recommendation in PDF format.

Prior to issuing their recommendation, the Line Siting Committee held hearings and a special public comment session about the Desert Basin project April 16-17, 2007 in Casa Grande, Ariz.

View the hearing notice in PDF format.

About the project

  • Project details and need: The Desert Basin 230kV power line project consists of a new 230kV transmission line that will provide a more reliable path between the SRP-owned Desert Basin Generating Station and customer load in Pinal and Maricopa counties.
  • Location: View a map of the approved alignment. (191K PDF)
  • Timeline and cost: SRP will begin construction in 2013 with a completion date in 2014. The total project, including the development of the Pinal Central substation, is anticipated to cost up to $35 million.
  • Project benefits: When completed, the Desert Basin power line project will:
    • Improve reliability: The Project will improve reliability of the Desert Basin Generating Station by allowing it to operate at full output without limitations. The project will also increase the overall reliability of the local system by adding more wire, which translates into more transmission paths over which power will flow.
    • Increase capacity: The project increases the ability to utilize the local transmission system by freeing up existing capacity currently obligated to exporting power from Desert Basin. Freeing up existing capacity will allow local utilities to better serve the greater Casa Grande area providing an economically positive solution for local utilities, as well as Desert Basin.
  • Route development: Route alternatives for the transmission line were selected with input through the public process. The project team conducted a very comprehensive public process. Meetings included:

    • April - May 2006: Stakeholder briefings
    • June 2006: Phase I; Planning workshop / Public open house meeting
    • July 2006: Stakeholder briefings
    • July 2006: Phase II; Planning workshop / Public open house meeting
    • December 2006: CEC Filing: Stakeholder briefings
    • December 2006: Phase III Planning workshop
    • January 2007: Public open house meetings
    • April 2007: Siting Committee Approval
    • June 2007: ACC Approval

  • Central Arizona Transmission Study - High Voltage (CATS-HV): The CATS-HV Study identifies future electrical needs of Casa Grande and the surrounding areas. The Desert Basin 230kV Project is an important component of the CATS-HV Study.
  • Fact sheet: View a fact sheet about the project (distributed to the public prior to the first open house in June 2006).

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  • June 2007: Certificate of Environmental Compatibility (CEC) approved by the ACC.
  • Design: 20082011
  • Energization: 2014

Compliance filing for PW-SEV/BRG

As part of the Desert Basin 230kV Project, the ACC approved SRP's request to add a 230kV circuit to the 500kV structures along a portion of the PW-SEV/BRG certificated route in Casa Grande. Find out more.

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Contact us

If you have a question or comment about the Desert Basin 230kV powerline project -- we want to hear from you. Just use our online comment form. You may also call 1 (800) 380-6123 for more information.

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*To view PDF files, you'll need Adobe Acrobat Reader if you don't have it. It is free and you will only need to download it once. Then, return to this page to view the report sections and maps.

SRP -- Delivering more than power