This is a Non-Federal dataset covered by different Terms of Use than

Electric Transmission Lines - California Energy Commission [ds1198]

Metadata Updated: March 8, 2018

The CEC Transmission Lines geospatial data layer contains electric power lines of transmission and some distribution or sub-transmission voltages covering California. Transmission lines can carry alternating current or direct current with voltages typically ranging from 110 kV to 765 kV. Transmission lines can be overhead and underground; underground transmission lines are more often found in urban areas. Sub-transmission lines generally carry voltages ranging from 33 kV to 100kV. These sub-transmission lines transmit power from higher voltage lines or other bulk power sources to local distribution network substations. An overhead power line can be single or double circuit. A single-circuit transmission line carries conductors for only one circuit. For a three-phase system, this implies that each tower supports three conductors. A double-circuit transmission line has two circuits. For three-phase systems, each tower supports and insulates six conductors. Single phase AC-power lines as used for traction current have four conductors for two circuits. Usually both circuits operate at the same voltage. In HVDC systems typically two conductors are carried per line, but in rare cases only one pole of the system is carried on a set of towers. The detailed descriptions on the structure type, material and circuit can be found at here. If you cannot access to the PDF, you may request us to send you a copy of the PDF.The transmission line, substation and power plant mapping database were started in 1990 by the CEC GIS staffs. The final project was completed in October 2010. The enterprise GIS system on CEC's critical infrastructure database was leaded by GIS Unit in November 2014 and was implemented in May 2016. The data was derived from utility companies and USGS topographic map. Some of the data was rectified from GE and Platts transmission line geospatial data. The sources for the transmission line digitizing are including sub-meter resolution of Digital Globe, Bing, Google, ESRI and NAIP aerial imageries, with scale at least 1:5,000. Occasionally, USGS Topographic map, Google Street View and Bing Bird's Eye are used to verify the precise location of a facility. The data was digitized from pole to pole for greater than or equal to 200 kV transmission lines. For transmission lines less than 200kV, the data was digitized on the pole gaps of approximately 1:5,000 or greater. All the data was digitized based on ground level of where a pole was planted.The transmission line was not digitized with one line segment from substation to substation. GIS Unit will merge the multipart lines into one segment in the future, after consulting with the Strategic Transmission Planning and Corridor Designation Office in identifying electricity flow between substation to substation or power plant to substation. Not all transmission line spatial data ended or started with a substation or power plant point spatial data. However, GIS Unit is current developing power plant and substation boundary spatial data which will enclose most of the transmission lines at both ends.

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Non-Federal: This dataset is covered by different Terms of Use than License: No license information was provided.

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Metadata Date February 28, 2018
Metadata Created Date February 23, 2018
Metadata Updated Date March 8, 2018
Reference Date(s) February 22, 2018 (publication)
Frequency Of Update asNeeded

Metadata Source

Harvested from State of California Geoportal

Additional Metadata

Resource Type Dataset
Metadata Date February 28, 2018
Metadata Created Date February 23, 2018
Metadata Updated Date March 8, 2018
Reference Date(s) February 22, 2018 (publication)
Responsible Party California Energy Commission (Point of Contact)
Contact Email
Access Constraints Use Constraints: DISCLAIMER: The California Energy Commission makes no warranties, whether expressed or implied, as to the suitability or accuracy of the product for any particular purpose. Any use of this information is at the user's own risk. For further information or suggestions concerning maps/data, please contact: California Energy Commission- Energy Facilities Siting Division \u2013 Cartography Unit, 1516 9th Street, MS48, Sacramento, CA 95814. For any further questions, please call Terry Rose or Fui Thong or Travis David at (916) 654-3902., Access Constraints: None
Bbox East Long -112.211877
Bbox North Lat 42.086920
Bbox South Lat 32.348423
Bbox West Long -124.294270
Coupled Resource
Frequency Of Update asNeeded
Harvest Object Id 74586181-2d4c-40e6-8140-84cd4e7d414a
Harvest Source Id bf0e0f99-7417-42e4-a627-e94c49cb4159
Harvest Source Title State of California Geoportal
Metadata Language
Metadata Type geospatial
Progress underDevelopment
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True

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