Idaho has approximately 640 miles of natural gas transmission pipeline operated by 2 companies. The network in Idaho is entirely interstate — long-haul trunk lines carrying gas across state borders rather than within them. Northwest Pipeline is the largest operator with 540 miles (84.4% of the state total).
The interactive map below shows every interstate and intrastate transmission pipeline in Idaho from the U.S. Energy Information Administration dataset. Click any pipeline for the operating company, type, and status. To compare Idaho to the rest of the country, see the national US natural gas pipelines map.
Idaho Natural Gas Pipeline Network at a Glance
All 640 mi is interstate transmission — high-pressure pipeline carrying gas across Idaho’s borders rather than within them. Every pipeline segment in the EIA dataset is currently flagged Operating; idled and retired transmission lines are not reported in the public data.
| Type | Miles | Segments | Share |
|---|---|---|---|
| Interstate | 640 | 41 | 100.0% |
- 41 total pipeline segments covering ~640 miles (EIA transmission dataset)
- 2 distinct operators own and run transmission infrastructure inside Idaho
- 0 miles intrastate (0.0%), 640 miles interstate (100.0%)
- The largest operator, Northwest Pipeline, accounts for 84.4% of Idaho’s transmission mileage
- The two largest operators control about 100.0% of the state’s pipeline miles between them
Pipeline Operators in Idaho
Northwest Pipeline runs the largest share of Idaho’s natural gas transmission network, with 540 mi of pipeline across 29 segments. Below are the top operators ranked by pipeline length inside Idaho. “Type” indicates whether the operator runs interstate trunk lines, intrastate distribution-class transmission, or both.
| Rank | Operator | Type | Approx. miles | Segments | Share |
|---|---|---|---|---|---|
| 1 | Northwest Pipeline | Interstate | 540 | 29 | 84.4% |
| 2 | Gas Transmission – Northwest | Interstate | 100 | 12 | 15.6% |
How Natural Gas Crosses Idaho’s Borders
Idaho connects to neighbouring states through these interstate pipelines — visible as blue segments on the map:
- Northwest Pipeline — 540 mi inside Idaho (29 segments).
- Gas Transmission – Northwest — 100 mi inside Idaho (12 segments).
About the Data on This Map
This map shows interstate and intrastate natural gas transmission pipelines — the high-pressure trunk lines that move gas between production areas, storage, and city gates. It does not show gathering lines (which collect gas from individual wells) or local distribution mains (which carry gas the last mile to homes and businesses).
Pipeline geometries and operator information come from the U.S. Energy Information Administration via its public ArcGIS REST FeatureServer. Per-state stats on this page are computed by intersecting that dataset with the Idaho state polygon (Census TIGERweb) and summing the intersected segments using haversine distance on the source line geometries. Pipeline diameter, installation year, and capacity are not included in the public dataset. Pipelines that cross Idaho’s borders are shown in their entirety inside the state polygon, so segments visible on this map may extend into neighbouring states.
Compare Idaho to Other States
Use the national US natural gas pipelines map to compare Idaho’s pipeline network to every other state — including total mileage, operator concentration, and the interstate/intrastate split.
