Idaho Power and Rocky Mountain Power announced plans in May, 2007, to build approximately 1,150 miles of 500-kilovolt transmission lines across Wyoming and southern Idaho.

The companies have more information and maps available on a project Web site as well as a project fact sheet (PDF) .

This project is required to meet customer load growth needs as well as increase transmission capacity and reliability for our respective service areas. The project is scheduled for line segments to be completed in phases between 2014 and 2018.

Under many conditions, Idaho Power’s lines are already at full capacity. As a transmission provider, the company has the obligation to plan and construct transmission facilities to ensure reliable electric service to customers—a process requiring seven to 10 years.

Purpose and Benefits

The proposed Gateway West transmission project will:

• Help meet the growing demand for electricity and economic development in the region;
• Improve transmission system reliability;
• Respond to customer requests for new transmission capacity;
• Respond to customer demand for increasing amounts of renewable energy, particularly wind energy;
• Strengthen the integrated transmission network;
• Relieve congestion on existing facilities.

Environmental Review

Together, Idaho Power and Rocky Mountain Power will conduct all necessary environmental analysis to comply with the National Environmental Policy Act (NEPA) and will work with the Bureau of Land Management (BLM) to create an environmental impact statement (EIS). The EIS is the basis for the BLM’s determination whether to issue right of way grants across federal lands. Additionally, coordination with other Federal and State environmental and permitting agencies will also be required.