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Transmission Lines

This dataset maps the physical transmission backbone of the US power grid as polyline geometry, tracing each line from one substation endpoint to the other.

HIFLDInfrastructure data
Download dataOpen on map
Native record
event_time x hifld_id
snapshot publication cadence
Evidence
Observed market data
Published observations from the named source
In Ask the Grid
Transmission on the ERCOT map
Geometry for the live grid surface

Overview

Each segment carries attributes including the owning utility and a voltage class, distinguishing the high-voltage bulk transmission corridors from lower-voltage feeders. With it you can see how regions interconnect, identify the major paths that move power across long distances, and reason about constraints, interties, and where new generation or load would need to tie in. The source is the Homeland Infrastructure Foundation-Level Data (HIFLD) electric power transmission lines layer.

Query contract

Preserve one canonical row per (event_time, hifld_id) before aggregating.

Analysis rules

  • Group only after preserving the declared grain: event_time, hifld_id.

Schema22

Column
Type
event_timeDateTime64(6, 'UTC')
hifld_idLowCardinality(String)
typeNullable(String)
statusNullable(String)
ownerNullable(String)
voltageNullable(Float64)
volt_classNullable(String)
inferredNullable(String)
sub_1Nullable(String)
sub_2Nullable(String)
naics_codeNullable(String)
naics_descNullable(String)
sourceNullable(String)
source_dateNullable(String)
val_methodNullable(String)
val_dateNullable(String)
shape_lengthNullable(Float64)
geometryNullable(String)
longitudeNullable(Float64)
latitudeNullable(Float64)
source_timeDateTime64(6, 'UTC')
ingested_atDateTime64(6, 'UTC')

Sample data

event_timehifld_idtypestatusownervoltagevolt_classinferredsub_1sub_2naics_codenaics_descsourcesource_dateval_methodval_dateshape_lengthgeometrylongitudelatitudesource_timeingested_at
2026-09-23 06:00:04.360398313412AC; OVERHEADIN SERVICENOT AVAILABLE138100-161NUNKNOWN306617TAP311000221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY, DVOF2019-03-01IMAGERY/OTHER2020-02-210.03862478947102392{"type":"LineString","coordinates":[[-112.498445254,33.4671634900001],[-112.496233116,33.4668060110001],[-112.495945728,33.4646601860001],[-112.461727102,33.464813459]]}-112.49594572833.46466018600012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313411AC; OVERHEADIN SERVICENOT AVAILABLE-999999NOT AVAILABLEYTAP310932TAP310933221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2020-05-08IMAGERY2020-05-080.015629097383613202{"type":"LineString","coordinates":[[-112.86007823,32.3816140910001],[-112.862525469,32.3753312060001],[-112.863303539,32.376340928],[-112.85874726,32.37024353]]}-112.86330353932.3763409282026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313410AC; OVERHEADIN SERVICENOT AVAILABLE132100-161YUNKNOWN308934TAP310930221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2018-11-02IMAGERY/OTHER2020-05-080.10180631323205826{"type":"LineString","coordinates":[[-113.12771155,33.52231175],[-113.127420335,33.522308391],[-113.127406875,33.521339234],[-113.12290294,33.5191891540001],[-113.110029354,33.5082938940001],[-113.031339695,33.5081549720001]]}-113.1229029433.51918915400012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313409AC; OVERHEADIN SERVICENOT AVAILABLE-999999NOT AVAILABLEYDELANEYTAP310929221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2018-11-02IMAGERY/OTHER2020-05-080.003221093628244746{"type":"LineString","coordinates":[[-113.034328306,33.4811275320001],[-113.031404325,33.482478746]]}-113.03140432533.4824787462026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313408AC; OVERHEADIN SERVICENOT AVAILABLE-999999NOT AVAILABLEYNOT AVAILABLENOT AVAILABLE221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2020-05-08IMAGERY2020-05-080.01951012992947963{"type":"LineString","coordinates":[[-113.180833,33.3783330000001],[-113.180149656,33.3778363550001],[-113.162284707,33.377625134],[-113.162277901,33.377121532],[-113.162573423,33.3771232170001]]}-113.16228470733.3776251342026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313407AC; OVERHEADIN SERVICENOT AVAILABLE-999999NOT AVAILABLEYNOT AVAILABLENOT AVAILABLE221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2020-05-08IMAGERY2020-05-080.011178321278387388{"type":"LineString","coordinates":[[-112.864758327,32.370584122],[-112.859838,32.3686209900001],[-112.859476511,32.3696561610001],[-112.859032867,32.3701655310001],[-112.855069157,32.371248016]]}-112.85947651132.36965616100012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313406AC; OVERHEADIN SERVICENOT AVAILABLE-999999NOT AVAILABLEYTAP310934NOT AVAILABLE221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2020-05-08IMAGERY2020-05-080.28352630963821446{"type":"LineString","coordinates":[[-113.162284707,33.377625134],[-113.160330273,33.3776140750001],[-113.160175777,33.3627836530001],[-112.988058201,33.3627836530001],[-112.981621123,33.3485230480001],[-112.911506483,33.3482259530001],[-112.904040901,33.3434516360001]]}-112.98805820133.36278365300012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313405AC; OVERHEADIN SERVICETXU POWER OR TXU ELECTRIC DELIVERY138100-161NTAP310986TAP310987221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLhttp://www.newmexicocare.org/images/maps/nm_transmission_sys.jpg2005-12-13IMAGERY2019-12-060.42133072510168446{"type":"LineString","coordinates":[[-102.90366487,31.71292814],[-102.746209,31.8818660000001],[-102.733443,31.8963150000001],[-102.728419,31.9016060000001],[-102.71672,31.9153870000001],[-102.705018,31.9295490000001],[-102.67681,31.9634310000001],[-102.665528,31.976505],[-102.655873,31.987418],[-102.637422,32.006129],[-102.61290346,32.0117847770001]]}-102.70501831.92954900000012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313403AC; OVERHEADIN SERVICEWESTERN AREA POWER ADMINISTRATION69UNDER 100NKOFUNKNOWN302152221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2020-01-08IMAGERY2020-01-080.5959659139580938{"type":"LineString","coordinates":[[-114.347376495,32.867873504],[-114.348722696,32.8670965810001],[-114.354422447,32.85581452],[-114.351462961,32.8542095070001],[-114.337609369,32.8502952800001],[-113.989823987,32.8664525840001],[-113.960999262,32.863376427],[-113.897311432,32.871579511],[-113.793405704,32.9031385970001],[-113.797353864,32.9166259250001]]}-113.98982398732.86645258400012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313402AC; OVERHEADIN SERVICEWESTERN AREA POWER ADMINISTRATION69UNDER 100NKOFUNKNOWN308372221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2020-01-08IMAGERY2020-01-080.15660202445885796{"type":"LineString","coordinates":[[-114.347376495,32.867873504],[-114.365482425,32.862508403],[-114.372964294,32.868778492],[-114.393201504,32.9086563830001],[-114.424345755,32.9503508010001],[-114.425933014,32.9529297460001],[-114.43037291,32.957665681],[-114.438477385,32.9621030480001],[-114.449964305,32.9659208580001],[-114.450067274,32.9656067770001]]}-114.42593301432.95292974600012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313401AC; OVERHEADIN SERVICEARIZONA POWER ELECTRIC SERVICE69UNDER 100YUNKNOWN308712TAP310931221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2020-01-07IMAGERY2020-01-070.00387425459783903{"type":"LineString","coordinates":[[-112.855069157,32.371248016],[-112.854900069,32.3751185790001]]}-112.85490006932.37511857900012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313400AC; OVERHEADIN SERVICEARIZONA POWER ELECTRIC SERVICE69UNDER 100YNOT AVAILABLENOT AVAILABLE221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2020-01-07IMAGERY2020-01-070.024909262028405006{"type":"LineString","coordinates":[[-112.830225674,32.369438959],[-112.855069157,32.371248016]]}-112.85506915732.3712480162026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313399AC; UNDERGROUNDIN SERVICEARIZONA POWER ELECTRIC SERVICE69UNDER 100NSTAGECOACHNOT AVAILABLE221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLhttps://www.aps.com/-/media/APS/APSCOM-PDFs/About/Construction-and-Power-Line-Siting/Power-Line-Siting/Power-Line-Siting-Projects/Northeast-Valley/October2013ProjectUpdate.ashx?la=en&hash=3EB8A93C133C96C72872261819FECC972016-01-01IMAGERY2020-05-080.03483371069395928{"type":"LineString","coordinates":[[-111.873202902,33.813342435],[-111.873221714,33.8139217450001],[-111.838967739,33.8138309500001]]}-111.87322171433.81392174500012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313398AC; UNDERGROUNDINACTIVEARIZONA POWER ELECTRIC SERVICE69UNDER 100NSTAGECOACHNOT AVAILABLE221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLhttps://www.aps.com/-/media/APS/APSCOM-PDFs/About/Construction-and-Power-Line-Siting/Power-Line-Siting/Power-Line-Siting-Projects/Northeast-Valley/NEValleyLineSitingUpdateMarch2016.ashx?la=en&hash=B5231EB23E7EA78A2BF1890DDBDF4DA32013-01-01IMAGERY2020-05-080.03397544370654584{"type":"LineString","coordinates":[[-111.873202902,33.813342435],[-111.83922767,33.813462375]]}-111.8392276733.8134623752026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313397AC; OVERHEADIN SERVICEARIZONA PUBLIC SERVICE COMPANY238220-287YUNKNOWN301046UNKNOWN308826221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2016-11-05IMAGERY/OTHER2020-02-210.10314498012852465{"type":"LineString","coordinates":[[-112.676324115,33.144803263],[-112.676491061,33.1444202960001],[-112.674770842,33.136784203],[-112.672652036,33.130742459],[-112.666862031,33.112764075],[-112.665906209,33.0438360100001],[-112.66625537,33.0432585360001]]}-112.67265203633.1307424592026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313396AC; OVERHEADIN SERVICENOT AVAILABLE138100-161NNOT AVAILABLENOT AVAILABLE221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2016-05-03IMAGERY/OTHER2020-01-160.01769062813718592{"type":"LineString","coordinates":[[-100.25324,35.198494],[-100.253241,35.2051440000001],[-100.253217,35.210807],[-100.253223,35.212883],[-100.253218,35.2135020000001],[-100.253194,35.2140210000001],[-100.253694,35.2147420000001],[-100.254184,35.2154630000001],[-100.254252216,35.2158711810001]]}-100.25321835.21350200000012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313395AC; OVERHEADIN SERVICEARIZONA PUBLIC SERVICE COMPANY138100-161YUNKNOWN308826GILA RIVER221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2016-11-05IMAGERY/OTHER2020-02-210.08259849423273301{"type":"LineString","coordinates":[[-112.66625537,33.0432585360001],[-112.665811242,33.042785445],[-112.665953323,33.0008364380001],[-112.677984802,32.9843808270001],[-112.683541942,32.9757483760001],[-112.692890101,32.975871125]]}-112.67798480232.98438082700012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313394AC; OVERHEADIN SERVICENOT AVAILABLE69UNDER 100YTAP310935TAP310937221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2020-05-08IMAGERY2020-05-080.008097298238540988{"type":"LineString","coordinates":[[-112.871376155,32.376068092],[-112.863475481,32.376418997],[-112.863303539,32.376340928]]}-112.86347548132.3764189972026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313393AC; OVERHEADIN SERVICENOT AVAILABLE138100-161YTAP310997CULBERSON221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2019-11-26IMAGERY2019-11-260.42346635451346587{"type":"LineString","coordinates":[[-104.304751,31.756811],[-104.322411,31.678551],[-104.34726,31.5673150000001],[-104.360822,31.4731390000001],[-104.375411,31.3771090000001],[-104.381176,31.3536310000001],[-104.393982,31.353615]]}-104.36082231.47313900000012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313392AC; OVERHEADNOT AVAILABLENOT AVAILABLE-999999NOT AVAILABLENMOHAVE ELECTRICTAP310938221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2018-04-13IMAGERY2020-05-120.09033089649109617{"type":"LineString","coordinates":[[-114.107558404,35.1999109810001],[-114.082706,35.189241],[-114.078235,35.187333],[-114.074183,35.185034],[-114.072967,35.184354],[-114.068974,35.1820530000001],[-114.067292,35.1811010000001],[-114.065595,35.1801540000001],[-114.061284,35.178503],[-114.059237,35.1765130000001],[-114.057561,35.1748230000001],[-114.056202,35.1736560000001],[-114.056191,35.1725640000001],[-114.056137,35.171122],[-114.054749,35.169434],[-114.050387,35.1668680000001],[-114.049156,35.1659680000001],[-114.045958,35.1636480000001],[-114.044877,35.1627950000001],[-114.03071,35.156239]]}-114.05756135.17482300000012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313391AC; OVERHEADNOT AVAILABLENOT AVAILABLE-999999NOT AVAILABLENUNKNOWN310939NOT AVAILABLE221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2018-04-13IMAGERY2020-05-120.006859597630354051{"type":"LineString","coordinates":[[-114.070597,35.1325860000001],[-114.070461356,35.133136624],[-114.068908746,35.138458697],[-114.068355612,35.138963109]]}-114.06890874635.1384586972026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313390AC; OVERHEADNOT AVAILABLENOT AVAILABLE-999999NOT AVAILABLENTAP310947UNKNOWN305924221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2018-04-13IMAGERY2020-05-130.13410948313602347{"type":"LineString","coordinates":[[-114.184425,35.0922831280001],[-114.184696,35.092275],[-114.107478,35.142596],[-114.071131,35.1328090000001],[-114.06724,35.131762]]}-114.10747835.1425962026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313389AC; OVERHEADNOT AVAILABLENOT AVAILABLE-999999NOT AVAILABLENHILLTOPUNKNOWN309636221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2018-04-13IMAGERY2020-05-130.08858511111859638{"type":"LineString","coordinates":[[-114.059548427,35.1890535200001],[-114.059713172,35.188621052],[-114.060017,35.1873820000001],[-114.059976,35.1853100000001],[-114.057405,35.185283],[-114.04992,35.1854700000001],[-114.04904,35.185345],[-114.04011,35.1794370000001],[-114.024874,35.1840920000001],[-114.020177,35.1811490000001],[-113.982753,35.1811870000001],[-113.980249568,35.177788148]]}-114.0490435.1853452026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313388AC; OVERHEADNOT AVAILABLENOT AVAILABLE69UNDER 100YUNKNOWN309636TAP310990221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2018-04-13IMAGERY2020-05-120.030434227084924992{"type":"LineString","coordinates":[[-114.059548427,35.1890535200001],[-114.059836,35.188584],[-114.061481,35.188069],[-114.062727,35.1886870000001],[-114.063551,35.1886680000001],[-114.063889,35.190145],[-114.066213,35.1903130000001],[-114.069117,35.190589],[-114.071605,35.192209],[-114.084948473,35.2014194340001]]}-114.06388935.1901452026-09-23 06:00:04.3603982026-09-23 06:01:05.254767
2026-09-23 06:00:04.360398313387AC; OVERHEADNOT AVAILABLENOT AVAILABLE-999999NOT AVAILABLENUNKNOWN307303HILLTOP221121ELECTRIC BULK POWER TRANSMISSION AND CONTROLIMAGERY2018-05-24IMAGERY2020-05-110.0405637846705193{"type":"LineString","coordinates":[[-113.980249568,35.177788148],[-113.982522,35.1812390000001],[-113.993396419,35.2160101320001]]}-113.98252235.18123900000012026-09-23 06:00:04.3603982026-09-23 06:01:05.254767

Coverage

14.4% complete77 gap days13 days with data
Show coverage history
Coverage: 14.4%Days with data: 13Gaps: 77
2026
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