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Crown Registry and Geographic Base
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In This Program Area
Latest Updates
BCACS News
Check the BCACS News page for the latest updates in the Geospatial Reference Unit.
Overview
The Geospatial Reference Unit (GSR) defines and manages the spatial coordinate system in the province to support geographic positioning activities according to established standards and professional practices.
The Geospatial Reference Framework consists of two main components - a physical monumented system (MASCOT) and a satellite positioning reference system (BCACS). Both systems provide compatible universal coordinates.
The Geospatial Reference Unit mandate is delivered through three working groups:
- Active Control System Group
- Geodetic Reference System Group
- Geodetic Database Management Group
Products
Our products and services fall into two broad categories: real-time GPS data and post-mission GPS data. Real-time data is available as it is being produced through a wireless link. Post-mission data is accumulated over time and packaged as large files for download.
Real-time data can be either low resolution (1-3m) GPS corrections or higher resolution Real-Time Kinematic (RTK) data (cm). Lower resolution real-time data is available for all of Canada, for free through the Canada-wide DGPS Service. Higher resolution RTK data is available, either for free or for a fee, from our BCACS Municipal data products: BCACSm–CRD, BCACSm–GVRD, BCACSm–Prince George.
Post-mission data is available from MASCOT, BCACS, and BCACSm for purchase, either through subscription or pay-per-download, at our Base Map Online Store.
The following is a list of products and services we provide.
MASCOT
The MASCOT system consists of a network of over 50,000 survey control monuments situated in the valleys and mountains throughout British Columbia. This network of monuments was established from mapping and control surveys conducted over the last century. During the 1960's, through a partnership between the provincial government and local governments, the physical control system was extended to developing areas. MASCOT is a database of the provincial control survey's physical system and provides published coordinates and elevations and related data for public access and use.
BC Active Control System (BCACS)
The newest component of the Geospatial Reference framework is the BC Active Control System (BCACS) which integrates satellite based positioning, broadcast communication and computer technologies to create a precise and accurate referencing system for the province.
The system currently consists of a network of twenty Global Positioning System (GPS) based satellite receivers strategically located to provide coverage across the province. The BCACS enables post-mission positioning within metres or centimetres to a myriad of land, air and water based navigators.
Access to the BCACS system post-mission data is provided through ftp downloads operated by the Geospatial Reference Unit in Victoria.
You can view information about our active control points on our BCACS Active Control Points Information Page.
BC Active Control System – Municipal (BCACSm)
The BCACSm is a system which provides GPS corrections in post-mission and real-time using the standardized Provincial coordinate system NAD83 (CSRS). Real-time communication is supported via a UHF radio link and/or wireless PCS link (i.e. cellular telephone). Real-time accuracy levels range from approximately 1m (using RTCM code corrections and a mapping grade GPS receiver) to centimetre level (using dual frequency survey grade receivers). It will provide users with the ability to survey and layout points, accurate to a few centimetres, instantaneously.
BCACSm has been implemented in three municipal areas:
- The Capital Regional District - see the BCACSm CRD product page.
- The Greater Vancouver Regional District - see the BCACSm GVRD product page.
- Prince George (in progress)
Education/Outreach
The Geospatial Unit offers publications supporting geospatial work, both downloadable PDF files and print-on-demand hard copies, as well as comprehensive RISC GPS training courses. More >>
Initiatives
The Canadian Height Modernization Initiative
The current height reference system is based on the Canadian Geodetic Vertical Datum (CGVD28), adopted in 1935, which was constructed using classical surveying techniques. The datum reference level was defined as mean sea-level determined from data collected at five tide gauges on the east and west coasts. The datum is accessed by users through an extensive network of precisely levelled benchmarks provided by government agencies. Historically, the definition of this height reference system has been separate from the definition of the horizontal reference system, but with the implementation of the Canadian Spatial Reference System, this is changing.
A number of limitations (described in technical papers provided) are associated with the continued use of CGVD28 including the cost of maintenance, coverage in remote areas, compatibility with the Canadian horizontal reference system and the height reference systems in other jurisdictions, accuracy and distortions in the system, and compatibility with modern space-based positioning technology.
GPS users require 3D positions referenced to the Canadian Spatial Reference System (CSRS) to ensure compatibility with data from other sources and to meet regulatory requirements. Therefore, the modernization of the vertical component of the CSRS is critical to providing Canadians with a truly three-dimensional integrated datum.
An opportunity exists to define a new datum that resolves the limitations of the current system - one that is compatible with international standards, enables cost-saving implementation of space-based technologies such as GPS, is easily accessible at any point in Canada, and is less sensitive to geodynamic activities and the deterioration of benchmarks. Such a system would be based on an accurate "geoid" model. More >>
Standards and Specifications
The Geospatial Unit maintains several provincial standards, specifications and guidelines in addition to a number of technical papers, brochures, and newsletters. Please check back frequently for updates to these documentation.
| Unit Standards, Specifications and Guidelines >> GPS Resource Specification (Release 4.0 April 2008) >> RTK GPS Guidelines (Ver. 1.1 - April 2008) >> | Unit Technical Papers >> Unit Brochures >> |
Frequently Asked Questions
Refer to our Frequently Asked Questions (FAQ) section to find out more about how our geospatial reference framework works.
Forms
For users wishing to apply for a "pay-per-download" account for the British Columbia
Active Control System (BCACS) FTP site or the MASCOT Survey Control/Web service, please
complete and return by fax the following form:
For users wishing to purchase a BCACSm–GVRD Subscription, please
complete and return by fax the following form:
Contacts
For contacts in the Geospatial Reference Unit, refer to the Contacts page.
