Horizontal and Vertical Control Networks

Vertical Control Network

The City of Santa Rosa's Vertical Control Network is based on the National Geodetic Vertical Datum of 1929 (NGVD 29).  There are over 1300 benchmarks located throughout the city as well as the surrounding area.

This system is tied directly and adjusted to USC&GS  (now the NGS)  Bench Marks in the area.

Data for City of Santa Rosa Bench Marks can be obtained through the City's GIS System. History and background information for the City’s Vertical Control Network is available.

 Horizontal Control Network

The City of Santa Rosa has two Horizontal Control Networks. The original older network is published with values based upon the California Coordinate System Zone 2, NAD 1927, the newer network with NAD 1983 (1991.35 epic) values. Although these systems were established independently some monumets have values in both systems. The NAD 83-91.35 values were established using GPS with adjustments to five High Precision Geodetic Network (HPGN) monuments within and surrounding the City.

Locations and data for City of Santa Rosa coordinate monuments can be obtained through the City’s GIS system. History and background information for these Horizontal Control Networks is available.