us_transmission_lines — US electric power transmission lines (HIFLD, 2024)

Description

Network of the electric power transmission lines of the United States (including Alaska, Hawaii, Puerto Rico and Guam), from the "Electric Power Transmission Lines" layer of the Homeland Infrastructure Foundation-Level Data (HIFLD) Open portal of the US Department of Homeland Security, in its last version (data current as of September 30, 2024). The layer was compiled from aerial imagery, the forms EIA-860 and EIA-861 of the US Energy Information Administration, OpenStreetMap and other public sources, and covers lines of 69 kV up to 765 kV, and some of lower voltage; underground lines are included where sources were available. The HIFLD Open portal was shut down in 2025; the data are taken from the copy archived (and no longer updated) on ArcGIS Online by Esri's Federal User Community.

In both networks each edge is a transmission line (94,619 in all). The layer gives the lines as geometries, with the names of the substations at their ends (SUB_1 and SUB_2) as attributes; most of these names are placeholders (e.g. "UNKNOWN128553" or "TAP139917"), and they are not always consistent between lines that meet at the same point, so the topology is given in two ways:

endpoints: the nodes are the end points of the lines (substations, taps and junctions), built from the geometries: two lines are joined at a node if they end at the same point (after rounding the coordinates to $10^{-7}$ degrees, about 1 cm). Lines that cross or touch each other elsewhere than at their end points are not joined. The network has parallel edges (4,502, e.g. circuits running side by side) and 24 self-loops (lines ending where they start); it is not connected (836 components, the largest with 72,103 nodes).
substations: the nodes are the substation names of the lines' ends, as given in the data (including the numbered placeholders, which identify taps, risers, dead ends and unknown substations); two lines are joined if they name the same substation. Names are not unique across the country (e.g. 96 line ends name a substation "MIDWAY", from Florida to Texas and California), so distinct substations of the same name are merged. Where a name is not available ("NOT AVAILABLE", 17,559 line ends), the end gets a node of its own, with an empty name. The network has parallel edges (3,532) and 186 self-loops (lines that name the same substation at both ends); it is not connected (5,610 components, the largest with 65,817 nodes).

The networks are undirected. The geometries of the lines (their courses as polylines) are not included, nor the constant attributes (the NAICS code of the industry), the layer's internal object ids, and its lengths of the lines in the Web Mercator projection, which are replaced by the lengths along the great circles.

The network has the following properties:

(Node) latitude, longitude (endpoints): the position of the end point.
(Node) name (substations): the name of the substation (empty if not available).
(Edge) hifld_id: the id of the line in HIFLD.
(Edge) type: the type of line (e.g. AC; OVERHEAD, AC; UNDERGROUND, DC; OVERHEAD).
(Edge) status: the status of the line (IN SERVICE, INACTIVE, UNDER CONSTRUCTION).
(Edge) owner: the owner of the line.
(Edge) voltage: its voltage (kV; NaN if not available).
(Edge) volt_class: the voltage class (e.g. 100-161, 345, DC).
(Edge) inferred: whether the voltage was inferred (Y or N).
(Edge) sub_1 and sub_2: the names of the substations at the ends of the line, as given in the data.
(Edge) source: the sources of the data.
(Edge) source_date: the date of the source (Unix time; -1 where missing).
(Edge) val_method: the method of validation (e.g. IMAGERY).
(Edge) val_date: the date of validation (Unix time; -1 where missing).
(Edge) length: the length of the line along its course (km, computed from its geometry). Values that are not available are empty strings.

Tags

Technological Power grid Spatial Weighted Multigraph Metadata

Added

2026-10-31

Citation

Homeland Infrastructure Foundation-Level Data (HIFLD), "U.S. Electric Power Transmission Lines." US Department of Homeland Security, dataset, archived on ArcGIS Online (2024) www.arcgis.com

Upstream URL OK

https://www.arcgis.com/home/item.html?id=d4090758322c4d32a4cd002ffaa0aa12

Upstream license

US Government work (public domain); Esri Master License Agreement (ArcGIS Online copy), https://www.esri.com/en-us/legal/terms/full-master-agreement

Networks

Tip: click on a column header to sort the list, or hover over it for a description.

Column legend

$\left<k\right>$: Mean degree
$\sigma_k$: Standard deviation of the degrees
$\lambda_h$: Largest eigenvalue of the Hashimoto (non-backtracking) matrix
$\tau$: Random walk mixing time
$r$: Degree assortativity
$c$: Global clustering coefficient
$\oslash$: (Pseudo-) diameter
$S$: Relative size of the largest component
NPs: Node properties
EPs: Edge properties

Name	Nodes	Edges	$\left<k\right>$	$\sigma_k$	$\lambda_h$	$\tau$	$r$	$c$	$\oslash$	$S$	Kind	Mode	NPs	EPs	gt	GraphML	GML	csv
endpoints	74,940	94,619	2.53	1.80	3.84	43657.86	0.19	0.04	103	0.96	Undirected	Unipartite	longitude latitude	hifld_id type status owner volt_class inferred source val_method sub_1 sub_2 voltage source_date val_date length	4.0 MiB	5.1 MiB	5.0 MiB	5.6 MiB
substations	81,291	94,619	2.33	2.15	4.40	2182.49	0.11	0.03	48	0.81	Undirected	Unipartite	name	hifld_id type status owner volt_class inferred source val_method sub_1 sub_2 voltage source_date val_date length	3.5 MiB	4.7 MiB	4.6 MiB	5.2 MiB

Ridiculograms^*

^* These are automatically generated force-directed visualizations, and can be quite meaningless for networks both big and small. They should not be taken seriously as sources of scientific insight. See here for a discussion.