Central Valley Chapter
California Land Surveyors Association

Promoting the professional practice of land surveying in the California Central Valley.
Serving the greater Merced, Stanislaus and San Joaquin County Area."


What is Trigstar?


Trig Star is an annual high school mathematics competition based on the practical application of Trigonometry. Students that participate are not only provided with an opportunity to earn awards, but also leave with a better understanding of the technical profession of Land Surveying and Mapping.


Professional Land Surveyors use the Trig Star program to advance communication with the communities they serve.

The purpose of the program is:

  • To promote the study of trigonometry in high school and to promote excellence in the mastery of trigonometry by honoring the individual student who has demonstrated superior skill among classmates at the High School level.
  • To acquaint the high school geometry and trigonometry students with the use and practical application of geometry and trigonometry in the surveying profession.
  • To build an awareness of surveying as a profession among the mathematically-skilled high school students, career guidance counselors and high school math teachers.

What happens during the Trig-Star Contest?

A presentation by a Land Surveyor to help participants understand the Land Surveying/ Geomatics Profession. The exam is a timed exercise, during which students must solve trigonometric problems that incorporate the use of the right triangle formulas, the law of sines, and the law of cosines. The student with the highest score and fastest time will be named the "Trig Star" for each high school participating in the program. The scores and times of the Trig Stars are reviewed to determine the State Winner and Runner-up in California. The State Winner will qualify to take the National Exam.

The Trig Star program is sponsored nationally by the National Society of Professional Surveyors.

Local Trigstar Coordinator

Bill Koch koch1313@yahoo.com

State Trigstar Coordinator

Annette Lockhart, Chair LadyLandSurveyor@gmail.com

Chapter News:

CLSA Sacramento Chapter Presents:

Dennis Mouland Seminar, September 15 and 16
Space is limited, reserve your slot today!

(see attached flyer)

Continous GPS Stations

A message from Rob McMillan:

Below are excerpts of emails from Unavco's Chris Walls and Sharon Williams of the National Science Foundation. Please read and respond to the survey at the link below. This is particularly critical if you perform any of the following:

  • Static GPS surveys
  • RTK GPS surveys using a virtual reference network (CSDS, Leica, Topcon, AZGPS, OCRTN, CVSRN, etc.)
  • Surveys tied to NGS control (the National Spatial Reference System (NSRS))
  • Surveys tied to the California Spatial Reference System (CSRS)
  • Surveys in state plane coordinates
  • Surveys tied to NAVD88 datum
  • Surveys tied to tidal datums
  • Surveys in areas of tectonic activity
  • Surveys using HTDP
  • Monitoring surveys (structural monitoring, dam deformation, etc)

This infrastructure also can support advancements in earthquake early warning, precision agriculture, automated machine guidance, autonomous vehicles, positive train control, and more.

Dear Colleagues, The future performance, capabilities, and station count of the Plate Boundary Observatory is at a crossroads. UNAVCO is currently developing budgets and plans for operating the network beyond 2018 including scenarios of reduced network density. If you rely on UNAVCO-provided PBO data then I recommend you make it clear what the uses are, what the regions of interest are, and even specific stations or data type (i.e. 1Hz, 5Hz, 15s, Met, real-time, seismic etc...). Please forward to collaborators who will miss the data if resources are not available.

PS - the survey will take 5-10 minutes, contrary to what is described below. Thank you for your participation.

Dear UNAVCO Users,
At the request of the National Science Foundation (NSF), the Science and Technology Policy Institute (STPI) has been asked to solicit feedback on the activities, products, and services provided by UNAVCO. NSF, UNAVCO, and STPI would all appreciate your time and response to this survey. The survey itself should take between 20-30 minutes. Your participation is completely voluntary. Your responses will not be shared individually and will not impact your relationship with NSF or UNAVCO. STPI is an independent, Federally Funded Research and Development Center and will be collecting and analyzing all responses. If you are a UNAVCO member or RESESS participant and have received a previous invitation to this survey, please disregard this email. We apologize for multiple survey invitations, but we are hoping for feedback from as many individuals as possible. Please feel free to contact Sharon Williams at STPI (swilliam@ida.org; 202-419-5411) or Russell Kelz (rkelz@nsf.gov; 703-292-4747) at NSF if you have any questions or concerns.

Survey link:

Next Scouting Merit Badge Session

Will be August 27th

Central Valley Chapter Awarded Chapter of the Year at 2016 Convention

Our Newsletter "The Prism" July 2016

California Surveyor: "Summer 2016"


BPELSG Example CBT Examination Questions:

BPELSG Bulletin: Spring 2016

New in the Library:

Tuolumne County - Updated Record Maps and Corner Records, added Mineral Surveys
San Joaquin County - added Filed Map Footprints
updated February 2016 Guide to the Preparation of Maps
updated ROS, PM, M&P, Corner Records
Madera County - updated Record maps
Santa Clara County - updated Record maps and Corner Records
Sacramento County - added link to Geographical Map Index
Fresno County - updated record maps
Stanislaus County - updated record maps

CLSA Chapter Website of the Year - 2012-2014