Welcome to the California Spatial Reference Center

The California Spatial Reference Center (CSRC) is responsible for “Establishing and maintaining an accurate state-of-the-art network of GPS control stations for a reliable spatial reference system in California.” The CSRC was established in 1997 as a partnership with surveyors, engineers, GIS professionals, the National Geodetic Survey (NGS), the California Department of Transportation (Caltrans), and the geodetic and geophysical communities.

The CSRC also maintains the California Real Time Network (CRTN), established in 2003 to (1) provide base station support for precise positioning (e.g., RTK surveys) and spatial referencing, (2) support research into earthquake early warning and response systems. CRTN rebroadcasts real-time data streams from multiple servers to registered users.

The CSRC is operated by the Scripps Orbit and Permanent Array Center (SOPAC) located at the Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics (IGPP) at Scripps Institution of Oceanography.

CRTN Community Notices

  • December 14, 2017: California’s GIS Council endorses the recommendations of the report “Maintaining California’s Geodetic Control System Strategic Assessment” prepared by the Geodetic Control Working Group.
    • February 26, 2018: Endorsed by League of California Surveying Organizations (LCSO)
    • March 28, 2018: Endorsed by County Engineers Association of California (CEAC)
    • April 9, 2018: Endorsed by American Council of Engineering Companies California (ACEC)
    • April 27, 2018: Endorsed by California’s Land Surveyor’s Association (CLSA)
    • April 30, 2018: Endorsed by Urban and Regional Information Systems Association (URISA)
    • May 5, 2018: Endorsed by Esri
  • CRTN transitioned to CSRS Epoch 2017.50 (NAD83) on March 1, 2018.
  • The CRTN Southern California server has a new IP (updated February 6, 2018):
  • The CRTN Northern California server has a new IP (updated August 5, 2017):
  • CRTN Registration: Allow 7-10 days for an account
  • Give a Gift to CRTN

Upcoming CSRC Events

CSRC Coordinating Council Fall Meeting in Northern California
Hosted by Jeff Little and PG&E at their Headquarters in San Francisco
October 19, 2018

CSRC Coordinating Council Spring Meeting in Southern California
IGPP, Scripps Institution of Oceanography (SIO), UC San Diego
April 11, 2019

More meeting specifics can be found here.

In February 2018, the CSRC published a new geodetic datum for California called “CSRS Epoch 2017.50 (NAD83)” under a Caltrans contract to SIO/SOPAC. The new epoch-date coordinates will be transmitted with RTCM 3.0 data streams starting March 1, 2018.