High Precision 3D Geodetic Networks
Canadian Basenet
The Canadian Base Network (CBN) is a network of pillars capped with a plate having a threaded bolt on which a GPS antenna or a theodolite can be screwed to. These pillars were positioned three-dimensionally with GPS to centimetre-level accuracy respective to the Canadian 3-D positioning standard NAD83(CSRS) at epoch 2002.0.
Canadian Base Network and CBN pillar in use
As well as being 3-D monuments useable by surveyors, the CBN serves as a monitoring network for deformation studies of the Canadian landmass.
The CBN is a federal primary 3-D control network however it was built in cooperation with provincial survey agencies. Most provinces have further densified the CBN network with their own High-Precision Networks.
CBN station descriptions are accessible via the CSRS Online Database. However, you can view the CBN stations via Google Earth (KML). Station locations can be downloaded from Geobase (as GML or shapefile) under "CANADIAN BASE NETWORK".
Related Information
- NAD83(CSRS) epochs
- Provincial HPN (High Precision Networks) available from the provinces
- Post-Glacial Rebound measured at CBN's
- Canadian Active Control System
Extended Federal 3D Network
This extended network consists in approximately 2000 (non-CBN) stations that were observed with high-accuracy GPS and tied to NAD83(CSRS) at epoch 1997 or 2002.
Extended Federal 3D Network
You will find 3-D NAD83(CSRS) coordinates for:
- Vertical benchmarks on which GPS was performed to verify the accuracy of geoid models and help produce the HTv2 height transformation
- Various older monuments originally tied using traditional survey methods and re-observed by GPS
Although the coordinates published are of centimetre-level accuracy
- some monuments may not be stable nor of geodetic quality construction
- some sites may not be ideal for GPS use (i.e. obstructions or multipath)
Full descriptions for the extended federal 3-D network are accessible via the CSRS Online Database. However, you can view the CBN stations via Google Earth (KML). Station locations can be downloaded from Geobase (as GML or shapefile) under "FEDERAL 3D DENSIFICATION NETWORK LEVEL 1".
GPS Validation Network
Geodetic Survey Division (GSD) provides GPS Validation Networks (GPS Basenets) sites across Canada. The Global Positioning System (GPS) has dramatically reshaped surveying and navigation in many parts of the world. The use of GPS positioning has become increasingly widespread. The need for a "truth" against which to test GPS positioning accuracy and precision has led to the establishment of GPS validation networks across Canada, also known as basenets, to serve as a physical standard for evaluating GPS equipment, software and positioning methodologies. The first GPS validation network was established in the Ottawa region in 1988. Since that time other such networks have been established across the country, in collaboration with the provincial agencies responsible for geodetic surveying within their jurisdictions.