ROUTE INFORMATION   
Route selection

The Bureau of Land Management (BLM) announced their Record of Decision (ROD) for segments 1 through 7 and segment 10 in November 2013, deferring the decision on segments 8 and 9. The BLM released its initial ROD for segments 8 and 9 on January 19, 2017.

On April 17, 2017, the Interior Board of Land Appeals (IBLA) remanded the January ROD back to the BLM Idaho State Office for reconsideration of the route alternatives. The BLM published a notice of intent to prepare an EA for segments 8 and 9 on August 28, 2017, beginning a 30-day scoping period. The Fiscal Year 2017 Consolidated Appropriations Act, signed into law May 5, 2017, included provisions from House Resolution 2104 to route the Gateway West transmission line through the Morley Nelson Snake River Birds of Prey National Conservation Area (NCA). As a result, the EA will address only those alternatives from the supplemental EIS that feasibly connect with the route specified in HR 2104. Rocky Mountain Power and Idaho Power will continue to work with the BLM through the environmental review process in support of a new ROD and right of way grant in compliance with HR 2104. For more information on the EA process, visit the BLM project website.

The companies are bound to the agency’s preferred routes, but only on federally-managed land. On privately owned land, the companies have more flexibility for transmission line siting within the study corridor. The companies will continue to work with individual landowners on “micro-siting” of the transmission line and have more detailed discussions as the design progresses.

The routes shown in this map reflect the BLM's authorized routes identified in the November 2013 ROD for segments 1 through 7 and 10, as well as the route identified in the January 2017 ROD for segments 8 and 9. The routes identified in the January 2017 ROD are currently being reconsidered by the BLM in compliance with HR 2104.
BLM authorized routes

The BLM’s authorized routes for segments 1 through 7 and segment 10 are:

  • Segment 1W(a) - Companies’ proposed route. The companies will pursue permitting only one new 230 kV line for Segment 1W(a) and reconstruction of the existing line for Segment 1W(c).
    Segment 1W(c) - Proposed Route. The companies will pursue permitting only one new 230 kV line for Segment 1W(a) and reconstruction of the existing line for Segment 1W(c).
  • Segment 2 - Companies’ proposed route including the substitution of Alternative 2C as part of the Rocky Mountain Power and Idaho Power’s revised Proposed Route.
  • Segment 3 - Companies’ proposed route.
  • Segment 4 - Companies’ proposed route including the substitution of Alternative 4A as part of the Rocky Mountain Power and Idaho Power’s revised Proposed Route.
  • Segment 5 - Companies’ proposed route and Alternative 5B. The BLM also supports Alternative 5E as part of its authorized route assuming Western Electricity Coordinating Council reliability issues are resolved.
  • Segment 6 - Upgrade the existing line voltage from 345 kV to 500 kV (no additional new line construction is required).
  • Segment 7 - Companies’ proposed route and Alternatives 7B, 7C, 7D, and 7G.The companies’ proposed route in the East Hills and Alternative 7G will be micro-sited to avoid Idaho’s Preliminary Priority Sage-grouse Habitat (PPH).
  • Segment 10 - Companies’ proposed route.

BLM’s January 2017 ROD for segments 8 and 9 was remanded back to the BLM Idaho State Office for reconsideration of routing alternatives in April 2017.

Companies proposed route revisions (February 2012)

In February 2012, Rocky Mountain Power and Idaho Power announced that Segment 1E would be removed from the project. The companies submitted a revised project application (known as an SF-299) to the BLM. These changes were considered when the BLM selected agency preferred alternatives. Changes included:

  • Segment 1 - Between the Windstar and Aeolus substations, the eastern 230 kilovolt segment (known as Segment 1E) of the project was removed from the project proposal. Segment 1W, as currently proposed, remains in the proposed project.
  • Segment 2 - Alternative 2C became the companies’ proposed route.
  • Segment 4 - Alternative 4A became the companies’ proposed route.
  • Creston substation - removed this proposed substation between Segment 2 and 3.
Route development history

All proposed, alternate and other routes analyzed in the draft and final EISs were developed with extensive study and planning and factored in input from state, local and federal agencies as well as private landowners. The companies developed initial routes through the following steps:

  • Established overall goals for routes
  • Evaluated opportunities and constraints using geographic information systems (GIS), field studies, and input from agencies and community leaders
  • Presented preliminary routes to the public during BLM scoping meetings held in June 2008 as well as company led landowner meetings between 2008 and 2009

Following scoping information, public comments and additional route analysis, the BLM determined which alternatives to carry forward for detailed analysis in the draft EIS, which contained rationale for alternative routes not analyzed in detail. The final EIS fully analyzes the BLM's preferred alternatives. A final decision on routing on public land for the project project in segments 1 through 7 and segment 10 was announced by the BLM in the November 2013 ROD. A draft supplemental EIS for segments 8 and 9 was released March 11, 2016, and the final supplemental EIS was published on October 7, 2016. The BLM released its ROD for segments 8 and 9 on January 19, 2017. IBLA remanded the January 2017 ROD back to the BLM Idaho State Office in April 2017 for reconsideration.

Field studies and land surveys

Idaho Power and Rocky Mountain Power continue to conduct studies and surveys to better understand conditions along the various corridors. The companies’ contractors are conducting land surveys, documented cultural and environmental conditions and collected soil borings. Information collected in these surveys helped inform the Bureau of Land Management's (BLM) EIS and will continue to inform the design and engineering of the project.

Please note that permission to enter private property for surveying and information gathering does not constitute a grant of future easement or that a transmission line will be constructed across the property, it is simply an allowance to conduct the studies. These studies do not mean a decision has been made on where to locate the transmission line.