Gateway West

The Gateway West project is jointly proposed by the company and Idaho Power to build and operate approximately 1,000 miles of new high-voltage transmission lines in Wyoming and Idaho. It is comprised of two major line segments:

Windstar to Populus, Segment D, will stretch approximately 488 miles starting at the Windstar substation near Glenrock, Wyoming, proceeding south to Medicine Bow and then spanning across southern Wyoming to the Populus substation near Downey, Idaho. This Segment D will include seven expanded or new substations and will enable access to existing and new generating resources, including wind, and will deliver electricity from these sources to customers.

On April 4, 2017, PacifiCorp issued its 2017 Integrated Resource Plan announcing plans to construct a portion of Segment D - Windstar to Populus. Independent of Idaho Power, PacifiCorp will initiate state and local permitting and right of way acquisition for 140 miles of 500 kV transmission line between the planned Aeolus substation near Medicine Bow, Wyoming and the Jim Bridger power plant near Point of Rocks, Wyoming.

Windstar to Populus, Segment D has been divided into three sub-segments:

  • D1 - Windstar to Aeolus: A single-circuit 230 kV line that will run approximately 75 miles between the existing Windstar substation in eastern Wyoming and the planned Aeolus substation near Medicine Bow, Wyoming.
  • D2 – Aeolus to Bridger/Anticline: A single-circuit 500 kV line running approximately 140 miles from the planned Aeolus substation to a new annex substation (Anticline) near the existing Bridger substation in western Wyoming.
  • D3 – Bridger/Anticline to Populus: A single-circuit 500 kV line running approximately 200 miles between the new annex substation (Anticline) and the recently constructed Populus substation in southeast Idaho. 

Populus to Hemingway, Segment E, originates at the Populus substation near Downey, Idaho, and includes two 500 kV single-circuit transmission lines that run approximately 502 miles across Idaho to the Hemingway substation near Melba, Idaho. The Populus to Hemingway segment will include five expanded or new substations, and will enable access to existing and new generating resources, including wind, and will deliver electricity from these sources to our customers.

Project Timeline:

  • Public Scoping – June 2008
  • Environmental Impact Statement – 2007 - 2013
  • Supplemental Environmental Impact Statement 2014 - 2016  
  • Public outreach – June 2008 through project completion
  • State and local permitting and obtaining rights of way – underway for segment D.2 Aeolus to Bridger/Anticline
    • Certificate of Public Convenience and Necessity application for segment D.2 submitted to the Wyoming Public Service Commission on June 30, 2017
  • Estimated line in service for customers – 2020 - 2024

Additional Information About the Project 

Under the National Environmental Policy Act, the Bureau of Land Management (BLM) has completed the Environmental Impact Statement (EIS) for the Gateway West project. The BLM released its final EIS on April 26, 2013, followed by the Record of Decision on November 14, 2013, providing a right-of-way grant for most of the project. The agency chose to defer its decision on the western-most portion of the project located in Idaho in order to perform additional review of the Morley Nelson Snake River Birds of Prey National Conservation Area. The BLM completed a supplemental environmental analysis for Segments 8 & 9 of the project which encompasses that area. On October 7, 2016, the BLM released its final supplemental EIS, followed by the Record of Decision on January 19, 2017. That Record of Decision was appealed to the Interior Board of Land Appeals. The Interior Board of Land Appeals remanded the January 19, 2017 Record of Decision back to Bureau of Land Management in April 2017. In May 2017, President Trump signed the Fiscal year 2017 Consolidated Appropriations Act into law which included Congressman Simpson’s agreement on Gateway West transmission line routing through the Morley Nelson Snake River Birds of Prey National Conservation Area. House Resolution 2104 (PDF) directs the Secretary of Interior to grant a right of way on the Companies’ preferred routing (Alternative 1).

Both companies will work with the Bureau of Land Management to continue through the Supplemental Environmental Impact Statement process for segment 8 (Midpoint to Hemingway) and segment 9 (Cedar Hill to Hemingway), in support of a new Record of Decision and right-of way grant for the remaining segments to comply with the House Resolution 2104. See map (PDF)

See below for additional information on public participation and project history, and visit the BLM website for more information.

Public Participation

Public input is an important part of the transmission line development process and is welcomed at all stages. In addition to public, group and individual meetings, project materials and newsletters also have been sent to more than 11,000 landowners and other interested parties throughout this process and will continue through the end of the project with continued web page and newsletter updates.

For a comprehensive list of meetings, publications and other public outreach, can be found on our Gateway West website.

To contact Rocky Mountain Power about this transmission project, please call the major construction projects message line at 801-220-4221, or email ConstructionProjects@pacificorp.com. Please be sure to include the project name – "Gateway West project" – in your inquiry.

Gateway West

Updated maps can be viewed below:

Further information also can be found at our Gateway West website

Next Steps

In light of the Interior Board of Land Appeals remanding the January 2017 Record of Decision back to Bureau of Land Management in April 2017, both companies will work with the Bureau of Land Management to continue through the Supplemental Environmental Impact Statement process for segment 8 (Midpoint to Hemingway) and segment 9 (Cedar Hill to Hemingway), in support of a new Record of Decision and right-of way grant for the remaining segments to comply with House Resolution 2104.

The Record of Decision and right-of-way grant contains many conditions and stipulations that must be met and accepted before the project can move to construction. The companies will continue the work necessary to meet these requirements. The companies will continue to meet regularly with the Bureau of Land Management to review progress.

There is more work to be done to obtain state and local permits, as well as obtaining rights of way for individual segments. The companies will continue evaluating the timing of next steps in the project to best meet our customer and system needs.

Project History

2017

  • January – The Bureau of Land Management issued a Record of Decision for the final two segments 8 (Midpoint to Hemingway) and segment 9 (Cedar Hill to Hemingway) for the agency’s preferred Alternative 5.
  • April – PacifiCorp issued its 2017 Integrated Resource Plan announcing plans to construct a portion of Segment D - Windstar to Populus. PacifiCorp will initiate state and local permitting and right of way acquisition for 140 miles of 500 kV transmission line between the planned Aeolus substation near Medicine Bow, Wyoming and the Jim Bridger power plant near Point of Rocks, Wyoming.
  • April – The Department of Interior Board of Land Appeals remanded the Record of Decision back to the Bureau of Land Management for reconsideration of the route alternative.
  • May – President Trump signed the Fiscal year 2017 Consolidated Appropriations Act into law which included Congressman Simpson’s agreement on Gateway West transmission line routing through the Morley Nelson Snake River Birds of Prey National Conservation Area. House Resolution 2104 directs the Secretary of Interior to grant a right of way on the Companies’ preferred routing (Alternative 1).

2016

  • March – The Bureau of Land Management published the draft Supplemental Environment Impact Statement.
  • April – The Bureau of Land Management conducted four public open house meetings.
  • April - July – The companies worked with the Bureau of Land Management to develop a mitigation framework plan to determine how mitigation requirements will be determined.
  • October – The Bureau of Land Management published the final Supplemental Environment Impact Statement.

2014

  • August – The Bureau of Land Management published the Supplemental Environment Impact Statement Notice of Intent and began the 30-day Public Scoping process.
  • October – The Bureau of Land Management conducted scoping meetings.

2013

  • April – The Bureau of Land Management issued a final Environmental Impact Statement and opened the 60-day comment period.
  • May – The Bureau of Land Management hosted a series of public open houses throughout the project area.
  • November – The Bureau of Land Management issued its Record of Decision for segments 1 through 7 (Windstar to Populus, Populus to Midpoint and Populus to Cedar Hill) and segment 10 (Midpoint to Cedar Hill). The Bureau of Land Management deferred their decision for segment 8 (Midpoint to Hemingway) and segment 9 (Cedar Hill to Hemingway). A separate Record of Decision will be released providing right of way grants for the remaining segments following additional environmental analysis.

2012

  • Throughout the year – Companies continued to meet with elected officials, community leaders and other interested parties to brief them on the status of the project.
  • August – The Bureau of Land Management identified agency preferred alternatives.
  • September – More than 12,600 newsletters (PDF) sent to landowners and interested parties providing an update on the project.

2011

  • Throughout the year – Companies continued to meet with elected officials, community leaders and other interested parties to brief them on the status of the project.
  • January – More than 11,200 newsletters (PDF) sent to landowners and interested parties providing an update on the project.
  • July 29 – Bureau of Land Management published in Federal Register a Notice of Availability announcing draft Environmental Impact Statement release, followed by a 90-day public comment period.
  • September/October 2011 – Bureau of Land Management hosted 17 public open houses on the draft Environmental Impact Statement throughout the project area.
  • October 28 – Draft Environmental Impact Statement public comment period closed.

2010

  • July – Environmental Assessment for Geotechnical Drilling released by Bureau of Land Management with finding of no significant impact.
  • August – More than 11,400 newsletters (PDF) sent to landowners and interested parties providing an update on the project.
  • September – Bureau of Land Management approved right of way grant to allow for geotechnical studies to be conducted on BLM-managed land.

2009

  • Throughout the year – Companies continued to meet with elected officials, community leaders and other interested parties to brief them on the status of the project.
  • January – Application filed with Bureau of Land Management to perform geotechnical studies along the routes.
  • March through November – Companies held public landowner meetings in various communities throughout Idaho and Wyoming.
  • July – More than 6,300 newsletters (PDF) sent to landowners and interested parties providing information about the project.

2008

  • Throughout the year – Both companies met with elected officials, community leaders and other interested parties to brief them on the project.
  • May 12 – Notice of Intent is issued by the Bureau of Land Management to notify the public that the public process for the project had begun.
  • June – Bureau of Land Management held nine public scoping meetings.
  • December – Companies held nine landowner meetings.

2007

  • May – PacifiCorp and Idaho Power filed an application with the Bureau of Land Management for an easement across federal lands.

(Updated August 2017)