California ISO GIS and Transmission Information Display System


Client: California ISO


The California Independent System Operator (ISO) is tasked with managing the transmission of electricity through the State’s network of high voltage lines. ISO’s control area is the second largest in the U.S. and fifth largest in the world. To support the management of the electrical grid in response to factors such as wild land fires and extreme weather, the ISO recognized that access to a geographically accurate representation of the grid through a GIS would be critical. The ISO asked Farallon to help develop the State’s first complete and positionally accurate electrical transmission grid by integrating raw data dumps from the State’s primary electricity generators and transmitters, including Pacific Gas and Electric Company, Southern California Edison, San Diego Gas and Electric, and the California Energy Commission.


Farallon developed a Unified GIS data model that successfully merged the State’s major power generators’ GIS data into a single, consistent, validated, and audited database. Highlights of the data model include:

  • Unified GIS Model: Development of a unified GIS data model that:
    • Can be used to support to support a wide array of ISO projects that require map production and database integration; and
    • Enables more robust control and management of ISO GIS data
  • GIS Data Development: Integration of vector and attribute data from multiple (10+) external sources and with multiple geographic map layers (including transmission lines, substations, power plants, towers and poles, utility service districts, political boundaries, roads, fire hazard zones and bodies of water)
  • System Documentation:
    • System configuration
    • Spatial data model structure
    • System update procedures
  • Mapping and Data Visualization Services: Farallon has developed and plotted a series of statewide transmission maps at varying scales (ranging from 1:24,000 map books to 1:1,000,000 wall maps)
  • Web Application: Farallon built and implemented a web-based GIS application to enable browser client access to the ISO GIS data, providing:
    • Integration with ISO’s real-time energy operating databases
    • A cost-effective and easy-to-use interface that allows local users to plot transmission maps on the fly

The ISO now has a well-designed, maintainable system-wide GIS, with a broad array of mapping capabilities, which can easily support integration with other ISO and external databases including California Division of Forestry wild land fire data and third party real-time weather feeds. In addition, the GIS model provided invaluable support for a high-profile engineering study.