Gateway West Segment E8 – Midpoint to Hemingway
Gateway West Segment E8 is a joint project with Idaho Power Company and is part of the Energy Gateway Program. This project is a key component to advance the goals of building resiliency, reliability and clean energy access in the Western energy grid. As part of the larger Energy Gateway Program, this project will consist of building a new 128-mile 500 kV transmission line between the existing Midpoint Substation in Jerome, Idaho, and the existing Hemingway Substation in Melba, Idaho. Expansions will be needed at both substations. Three signal regeneration stations will also be constructed along the line.
Gateway West Segment E8 will increase capacity between Midpoint West and Boise East by approximately 2,000 megawatts and relieve constraints on the transmission system between the Magic Valley and the Treasure Valley.
Midpoint to Hemingway Project Website & Interactive Map
Midpoint to Hemingway Map (subject to change)
Public outreach
Spring 2025 meetings
A series of public open house meetings were held in March and April 2025 in Marsing, Melba, Kuna, Glenns Ferry, Mountain Home, Gooding and Jerome, Idaho.
For those unable to attend in person, here's the virtual presentation: Spring 2025 Virtual Open House Presentation
Q&A from the Virtual Open House Presentation
December 2025 neighborhood meetings in Ada County:
Melba
Tuesday, December 16, 6-7 p.m.
Melba Senior Center
115 Baseline Rd.
Melba, ID
Boise
Wednesday, December 17, 6-7 p.m.
Boise Stage Stop
23801 S. Orchard Acres Rd.
Boise, ID
Public comments
Submit your comments regarding the project below:
Project timeline
- Design & Engineering: June 2024 – June 2026
- Project Surveying: June 2024 – June 2026
- Right of Entry & Right of Way: May 2024 – September 2027
- Local/State Permitting: January 2025 – June 2028
- Construction: March 2028 – June 2030
- Hemingway to Mayfield section complete: November 2028
- Mayfield to Midpoint section complete: June 2030
- Completed/In-Service: June 2030
More information
Requests for additional information on the Midpoint to Hemingway Gateway Segment E8 project may be directed to call (208) 288-6142 or email info@gwwe8.com.
Please include your request, along with your contact information and preferred contact method.