Pull to refresh
Logo
Idaho-Nevada transmission line starts construction after decades of planning

Idaho-Nevada transmission line starts construction after decades of planning

Built World

285-mile SWIP-North segment completes a 576-mile corridor linking Idaho wind to California demand

Yesterday: Construction officially underway

Overview

Updated 1 hour ago

A 285-mile transmission line connecting Idaho to Nevada broke ground September 3 in Ely, Nevada. It is the final segment of a corridor first conceived in the 1980s. The line serves two directions at once: California wants Idaho wind moving south, Idaho wants Desert Southwest power moving north.

The Southwest Intertie Project-North (SWIP-North) segment costs more than $1 billion and is expected online in 2028. Once energized, the full 576-mile corridor moves up to 2,000 megawatts in either direction. Idaho Power holds 500 megawatts of northbound capacity; California's grid operator gets direct access to Idaho wind.

Why it matters

If the line slips, Idaho faces grid shortfalls and California loses its one active route to Idaho wind power.

Questions about this story

Free account needed to ask — your question is kept and asked for you right after sign-up. Answers are public.

No questions yet — be the first to ask.

Key Indicators

2,000 MW
Bidirectional capacity once corridor completes
Full Southwest Intertie Project moves 2 gigawatts either direction, with 500 MW northbound for Idaho Power.
285 miles
Length of SWIP-North segment
Runs from Midpoint Substation near Twin Falls, Idaho to Robinson Summit Substation near Ely, Nevada.
$1 billion+
Project investment
LS Power's total investment in the SWIP-North transmission line.
$331 million
DOE federal commitment
Department of Energy funding committed in May 2024 to help advance the project.

Voices

Curated perspectives — historical figures and your fellow readers.

Ever wondered what historical figures would say about today's headlines?

Sign up to generate historical perspectives on this story.

Play

Exploring all sides of a story is often best achieved with Play.

Most of these play right now — no account needed. Sign up to save scores, keep a streak, and unlock Debate and Predict. Log in Sign Up
Predict 3 ways this could play out. Back the one you believe — contrarian picks score more when a scenario has a resolution date. Log in to play

People Involved

Organizations Involved

Timeline

1980s September 2026

10 events Latest: Yesterday
Tap a bar to jump to that date
  1. Construction officially underway

    Latest Milestone

    Engineering News-Record confirms the $1B-plus line is in construction, decades after first conceived.

  2. Groundbreaking in Ely, Nevada

    Milestone

    Nevada Governor Joe Lombardo joins LS Power officials to mark the start of construction.

  3. Right-of-way nearly secured

    Milestone

    California ISO reports 99% of right-of-way acquired, project on track for June 2028 operation.

  4. Nevada regulators approve construction

    Regulatory

    Nevada gives the green light for the portion of the line crossing its state.

  5. Idaho regulators approve 500 MW deal

    Regulatory

    Commission approves Idaho Power's participation, citing projected shortfalls without the line.

  6. DOE commits up to $331 million

    Funding

    The US Department of Energy backs the roughly $1 billion project with federal capacity funding.

  7. California ISO selects Great Basin

    Decision

    CAISO picks LS Power's Great Basin Transmission to develop the SWIP-North segment.

  8. DesertLink segment begins delivery

    Construction

    The 60-mile DesertLink line connects the corridor to the California ISO grid.

  9. First corridor segment enters service

    Construction

    One Nevada Transmission Line, a 231-mile segment from Robinson Summit to near Las Vegas, goes live.

  10. Southwest Intertie corridor conceived

    Planning

    The idea of a high-voltage corridor linking Idaho and Nevada first takes shape.

Historical Context

2 moments from history that rhyme with this story — and how they unfolded.

Completed 1970

Pacific DC Intertie (1970)

The Bonneville Power Administration and Los Angeles Department of Water and Power completed an 846-mile, 3,100 megawatt direct-current line carrying Columbia River hydropower to Southern California.

Then

It eased California's summer peaking strain and gave the Pacific Northwest a market for surplus hydro.

Now

It set the template for trans-regional power exchange in the West, the backbone of the region's grid economics for five decades.

Why this matters now

SWIP-North is the modern version of the same trade: surplus power where it's generated (Idaho wind) moving to where demand is (California), with return capacity for Desert Southwest power.

Groundbreaking June 2023

TransWest Express (2023)

Groundbreaking on the TransWest Express, a 3,000 MW high-voltage line bringing Wyoming wind through Utah to southern Nevada. Construction continues with expected service in the late 2020s.

Then

The line will deliver Wyoming wind generation to California load centers once complete.

Now

It joined a wave of long-haul Western transmission projects showing how wind-rich states become export hubs.

Why this matters now

TransWest and SWIP-North move in parallel: both are Western corridors built on California-ISO access logic and both target 2028-era in-service dates, reflecting the region's coordinated push to move remote wind to population centers.

Sources

(6)