Pierce County    


In cooperation with the NGS Cooperative CORS program.


Cooperative CORS

Northwest Region CORS Stations


Pierce Co. Control database


Solar Weather information

GPS Calendar



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Frequently Asked Questions:

Can I receive RTK corrections even though I do not use Leica equipment?

  • Yes. Because our base stations have been configured to transmit using the public domain CMR format any RTK receiver which can be configured to receive the CMR message.

What communications device do I need to use to receive the RTK message?

  • Currently we are transmitting the CMR message over cell phones. Please contact Pierce County Survey Section office to receive specific assistance.

How do I download static files for post-processing?

  • Follow the RINEX DATA FILES link found on the individual site pages. The data directory structure is listed by year, day of year, then UT hour of day.

What if the static file is not posted on the webpage for me to download?

  • Try again a little later, the data download may not have completed yet due to traffic on the network. The static files are downloaded to the server at the top of each hour, typically the download takes approximately five minutes to complete. If the communications network has been busy, these static files may be behind schedule. In these cases, downloads will occur as soon as possible, in the order in which they were logged.

What is happening when I get a voicemail message on the cell phone when trying to connect with a base station for RTK?

  • The RTK message should begin within the first 4-5 rings. If you get a voicemail message it means the connection has not been successful due to the wireless communications network traffic. Continue trying until a successful connection is accomplished.

What geodetic reference system are the base station coordinates in?

  • The Pierce County CORS are defined on the NAD83(HARN91) realization in accordance with WAC 332-130-060.


For questions dealing with the PC3N Network, User Accounts, and Survey Control;
Please contact: Mark Holden P.L.S. GPS/CORS Survey Lead
Phone: 253-798-3221 or by email:

For more information on Leica Real Time Networks contact:
Jill R. Johnson PLS, GPS CORS Network Engineer
Phone: 360-250-6358 or by email:

DATA USE WARNING: We provide these data in good faith and shall in no event be liable for any lost profits, and special, indirect or consequential damages to any party, arising out of or in connection with the use or the inability to use the data hereon or the services provided. We provide these data and services as a convenience to the public. Furthermore, we reserve the right to change, revise, or otherwise discontinue published data and/or these services at any time without further notice.