Canadian Spatial Reference System (CSRS) modernization

The Canadian Spatial Reference System (CSRS) underpins how coordinates are defined and used across the country. Reference systems are designed to reflect our understanding of the Earth’s size, shape, origin, and orientation based on the best available data at a given point in time. For decades, the CSRS has supported mapping, surveying, engineering, navigation, and many other activities that rely on accurate positioning. However, continued improvements in positioning accuracy expose limitations of reference systems based on older technologies, highlighting the need for the national reference system to evolve in line with modern capabilities.

Modern positioning relies heavily on global navigation satellite systems (GNSS), which operate within an Earth-centred (geocentric) reference system. While Canada’s reference system has been improved over time through successive reference frame realizations, the system itself remains non-geocentric. Addressing this fundamental limitation is a central objective of the CSRS modernization.

Beyond this technical consideration, CSRS modernization is also driven by the need for consistency across jurisdictions. Many positioning, navigation, and mapping applications operate across provincial, territorial, and national borders, making consistency essential. The modernization effort reflects collaboration both within Canada and across North America to achieve the desired consistency.

This page explains how the CSRS has evolved to its current state, what changes are coming as part of the current modernization, and how these changes will impact users. It also outlines what users can expect during the transition period and where to find tools and guidance.

Evolution of CSRS

Canada’s spatial reference system has evolved over several decades in response to advances in positioning technology and changing user requirements. Each stage of development has extended the reference system’s capabilities while maintaining continuity with existing practices and data.

In the late 1990s, the North American Datum of 1983 (NAD83) was extended to form NAD83(CSRS), providing Canada with a three-dimensional reference system capable of supporting satellite-based positioning. This marked an important transition, allowing ground-based surveys to be directly connected to observations from GNSS.

Subsequent enhancements further strengthened the reference system. In particular, the introduction of a national intra-plate velocity model enabled more consistent integration of datasets collected at different times. This improved the management of higher-accuracy positioning data within the national framework.

Attention then turned to Canada’s vertical reference system. The adoption of the Canadian Geodetic Vertical Datum of 2013 (CGVD2013) replaced earlier levelling-based approaches with a gravity-based vertical datum, providing a more consistent and reliable method for height determination across the country. This change addressed long-standing distortions that had accumulated over decades of levelling surveys and established a vertical reference system fully compatible with GNSS.

CSRS modernization represents the next step in this progression. It combines updates to the geometric reference system with a new realization of Canada’s vertical datum, aligning the national framework more closely with modern positioning technologies and international standards. Through coordinated adoption across jurisdictions, this modernization ensures that Canada’s spatial reference system remains robust, consistent, and fit for future applications.

CSRS Modernization Details

At its core, CSRS modernization involves updating two closely related components: the geometric reference system used to define positions, and the vertical reference system used to define heights. This includes adopting a new geometric reference system, NATRF2022, to replace the current NAD83(CSRS) reference system, along with an updated realization of Canada’s vertical datum, CGVD2013.

NATRF2022 is defined as a plate-fixed, geocentric reference system that combines the strengths of both global and regional reference systems. It is aligned to the International Terrestrial Reference Frame of 2020 (ITRF2020) at epoch 2020.0, ensuring compatibility with satellite-based positioning, while remaining fixed to the North American tectonic plate using an improved set of plate rotation parameters to support stable horizontal coordinates across Canada. This balance improves consistency between Canadian positioning practices and those used internationally, while reducing the risk of misinterpretation when integrating GNSS-based results. NATRF2022 also includes an improved intra-plate velocity model to capture any residual crustal motion and to allow users to combine and compare datasets collected at different times.

CSRS modernization also includes an update to Canada’s vertical datum. As part of a coordinated North American initiative, a new continental geoid model, GEOID2022, has been developed to provide a more accurate and consistent reference surface for height determination. In Canada, this model supports CGVD2013 v1, a new realization of CGVD2013. While the vertical datum itself remains CGVD2013, the updated realization benefits from major advances in geoid modelling, including higher-quality satellite gravity observations, new airborne gravity data from the U.S. GRAV-D mission, an improved digital elevation model, and the incorporation of newly available data from U.S. and Mexican partners. Together, these improvements significantly enhance the accuracy and ensure better consistency and alignment of height reference surfaces across North America.

Adopting NATRF2022 and the updated vertical realization does not change the physical locations of features on the ground, nor does it change how positions or heights are measured in the field. Instead, it updates the mathematical framework used to define and relate coordinates and elevations within Canada’s national spatial reference system, ensuring it remains compatible with modern positioning technologies and international standards.

Impacts of Modernization

The modernization of Canada’s spatial reference system affects how coordinates and heights are defined, managed, and interpreted, but it does not fundamentally change how most users collect data or carry out day-to-day work. Field practices, measurement techniques, and operational workflows used by current users of NAD83(CSRS) and CGVD2013 can continue as they do today.

For many users, the primary impacts of modernization relate to how coordinates and heights are expressed and referenced, rather than how they are measured. One of the most visible impacts of adopting NATRF2022 is a shift in horizontal coordinate values. Coordinates expressed in NATRF2022 will differ from NAD83(CSRS) by approximately one to two metres across Canada. This shift reflects the difference between reference systems and does not indicate any physical movement of features on the ground.

NATRF2022 also incorporates a more accurate representation of the rotation of the North American tectonic plate. This updated plate rotation model reduces residual horizontal motion present in NAD83(CSRS), resulting in a more stable and internally consistent horizontal reference system for Canada.

On the vertical side, the modernization includes a new realization of Canada’s vertical datum based on an updated geoid model. While the underlying vertical datum remains CGVD2013, the updated realization improves the overall accuracy, while also providing consistent heights across North America. Users will continue to work with geoid-based heights, and the way heights are accessed and applied will remain the same.

Geodetic tools and services will increasingly support NATRF2022 and the updated realization of CGVD2013 by default. At the same time, these tools will continue to support NAD83(CSRS) and earlier realizations of CGVD2013 throughout the transition period. Defined transformations between NAD83(CSRS) and NATRF2022, as well as conversions between versions of CGVD2013, will be provided to allow users to relate existing datasets to the modernized systems in a consistent and controlled way.

Another important impact of modernization is how existing spatial data are managed over the long term. Many organizations maintain extensive archives of data collected under NAD83(CSRS) and earlier vertical realizations. These datasets do not become invalid. However, organizations will need to migrate or relate existing datasets to NATRF2022 and/or the updated realization of CGVD2013 as part of ongoing data maintenance. These transformations and conversions will be formally defined in geodetic registries, such as EPSG and the ISO geodetic registry, to support consistent implementation.

The Canadian Geodetic Survey (CGS) is working with geospatial software developers and standards organizations to support the implementation of the modernized reference systems. As definitions, transformations, and metadata standards are incorporated into software and registries, the goal is for many conversions to be handled automatically where appropriate, reducing manual intervention and minimizing the potential for error.

For users already working with the dynamic realization of NAD83(CSRS) and the geoid-based height system (CGVD2013), the impacts of modernization will primarily involve changes in coordinate and height values rather than significant changes to workflows. In contrast, users still working in older legacy reference systems such as NAD83(Original) or CGVD28 are likely to experience more noticeable impacts as they transition to the modernized systems.

Overall, the impacts of CSRS modernization are intended to be evolutionary rather than disruptive. The updated framework provides a clearer, more consistent foundation for managing geospatial data while preserving continuity with existing practices and datasets. By supporting both new and legacy systems during the transition, modernization allows users to adopt the updated reference system in a controlled and predictable manner.

Transition Timeline

The transition to NATRF2022 will take place over several years and is designed to be gradual. Rather than a single changeover date, adoption of the new reference system will occur in phases. This approach allows users time to prepare, test workflows, and maintain continuity with existing data.

The timeline below outlines the general stages of adoption and how the transition is expected to unfold across jurisdictions.

  • The transition to NATRF2022 will be phased, not immediate.
    Adoption is planned as a gradual process to support understanding, testing, and adjustment across a wide range of users and applications.
  • Federal adoption is planned for early 2027.
    Federal geodetic and positioning activities will begin operating in NATRF2022 at this stage, marking the formal start of the national transition.
  • Provincial and territorial adoption is planned for 2030.
    Provinces and territories will adopt NATRF2022 on timelines that reflect their own mandates, systems, and operational needs.
  • A period of coexistence is expected.
    NAD83(CSRS) and NATRF2022 will be used in parallel during the transition, allowing users to continue working with existing datasets in NAD83(CSRS), while preparing for the migration to NATRF2022.
  • Tools and guidance will support the transition.
    CGS will provide resources to help users understand how to work with NATRF2022 and manage relationships between reference frames.
  • Full national alignment will occur over the longer term.
    The transition is expected to extend toward the end of the decade, reflecting the scale and complexity of adoption across Canada.

Beta Products and Tools

As part of CSRS modernization, CGS is developing and releasing a set of beta products and tools to support users preparing for the transition. These resources support both the adoption of NATRF2022 and the updated realization of CGVD2013 (CGVD2013 v1) and are intended to help users begin working with the modernized reference systems.

Beta products and tools are provided to help users understand how the modernized CSRS is applied in practice. They support testing and exploration, particularly for users who manage spatial data across multiple projects or need to understand how coordinates and heights change between reference systems.

These resources may support activities such as relating coordinates between NAD83(CSRS) and NATRF2022, and heights between the current and future realizations of CGVD2013. Where applicable, tools will also support continued use of NAD83(CSRS) and earlier realizations of CGVD2013.

Beta products and tools are intended to support learning and preparation for the transition. They are not final and should not be used for production work until they are officially adopted as they are subject to change.

The first beta release, planned for February 2026, will include links to download the following products and services:

NATRF2022

CGVD2013 v1

  • BYN format versions of the static geoid and deflection of the vertical models (SGEOID2022 and SDEFLEC2022).
  • BYN format conversion grids between the modernized version of CGVD2013 (v1) and the currently adopted version (v0a) at reference epochs 1997, 2002, 2010, and 2020.
  • Beta version of GPS-H desktop software with support for CGVD2013 v1 models (geoid and deflections of the vertical) and NATRF2022.

Summary

In summary, CSRS modernization is intended to address the limitations in the current reference system by:

  • Adopting a geocentric reference system that better supports GNSS and technologies relying upon GNSS (e.g., autonomous vehicles).
  • Adopting an improved geoid model for determining heights that will be consistent across North America.
  • Providing an opportunity to unify reference frame adoption across provincial, territorial, and national jurisdictions, making the CSRS simpler and more efficient for many applications.
 
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