New Datums Frequently Asked Questions (FAQs)

NGS is releasing the following key details for the transition to the new datums in the modernized NSRS to help users and interested parties prepare for the coming change:

1. NGS will roll out components of the modernized NSRS for public testing over time (2024 - 2026). As each component is released on the URL beta.ngs.noaa.gov, it can be publicly tested with feedback provided to NGS. The testing will continue for at least 6 months after the final component is released on beta.ngs.noaa.gov.
2. While the modernized NSRS is being rolled out and tested, the current NSRS will remain the official NSRS of the United States. The NGS website will only hold the official NSRS – currently NAD 83, NAVD 88, etc. Only one major improvement to the current NSRS is expected during this time: The International Terrestrial Reference Frame of 2020 (ITRF2020) will be integrated into all products and services to meet requirements that the NSRS remain consistent with accepted international standards. This is expected to happen in mid to late 2024 or early 2025.
3. Once enough testing by stakeholders is done, and all modernized NSRS components seem stable and correct, the Federal Geodetic Control Subcommittee (FGCS) will be asked to vote to approve the modernized NSRS and new datums (likely in mid 2026). If affirmative, another Federal Register Notice will be released and NGS will begin a several-months long process of transitioning all modernized NSRS components to the official NGS website. During this transition, the Beta website that will contain all the components of the modernized NSRS while in the testing phase, may be wiped of submitted data and no further submissions to the NGS Integrated Database (IDB) (the repository for the current NSRS) will be allowed.For more detailed milestones, visit Track Our Progress.

Visit the Get Prepared page to learn how you can prepare for the modernized NSRS.

Yes, terms containing “2022” such as “GEOID2022” and “NATRF2022” will remain the same. As explained in the Blueprint documents, the use of 2022 in the name does not carry any scientific meaning, but rather allows for a common term which links each of these pieces as belonging to the “modernized NSRS.” Also, since the names have been in the public domain for over 3 years now, changing them is likely to cause unnecessary confusion. (This is a not-uncommon occurrence: The release of NAD 83 in 1986 and the release of NAVD 88 in 1991 did not seem to cause undue harm or confusion, and therefore NGS will maintain the “2022” names.)

Many SPCS2022 zone definitions and projection equations have been released on Alpha but not all. Once finalized, the incomplete version of SPCS2022 on Alpha will be deleted, and the complete version of SPCS2022 will be released on Beta as one more component of the modernized NSRS.

NGS plans to continue to hold events to engage stakeholders as we work to modernize the NSRS. The number and types of events are currently under evaluation.

NGS is updating OPUS-S to support multi-GNSS static baseline processing. Previously designed around PAGES (NGS’s GPS-only processing engine), OPUS-S has been redesigned to use M-PAGES, which is NGS’s new software to process static GNSS data.

NGS will publish a Federal Register Notice (FRN) at key points in the phased rollout process: 1) October 2024 NGS announced the rollout process and timeline; 2) in late-2025 to announce all components are available on Beta for testing; and 3) in 2026 after the Federal Geodetic Control Subcommittee (FGCS) approves the modernized NSRS and the modernized NSRS is official and available on the NGS website.

Yes.

Section 2809 of the Geospatial Data Act of 2018 specifies that all federal civilian agencies that collect, produce, acquire, maintain, or disseminate geospatial data will be required to use the new reference frames within 5 years of being adopted by the FGDC as part of the NSRS. These agencies must use geodetic control to accurately register spatial data, and the NSRS is the fundamental geodetic control for the United States.

In addition, any state agency or organization receiving funds from the federal government to generate or process geospatial data must conform to the modernized NSRS. For those not part of federal agencies, using geodetic control to accurately register spatial data and not receiving funds from the federal government should conform with applicable state or local laws or contract terms. In many cases, there are advantages to using the NSRS and current reference frames.

A collaborative committee, with representatives from the National Society of Professional Surveyors (NSPS), the American Association for Geodetic Surveying (AAGS), and NGS developed a legislative template to assist with this situation. The template is meant to be used as an addendum to existing state laws and relies upon generic language (“most recent datum”, “NGS or its successors”, etc) so that the need for future legislative changes can be avoided.

The current version of the template, legislation examples, and other information are available on the NGS Get Prepared web page. The NSPS has taken on the responsibility of assisting state legislative bodies in drafting the new legislation for their state. Please direct questions to them. Examples of 11 new state legislations are available for download.

The NSRS will be accessed primarily using Global Navigation Satellite System (GNSS) technology that references Continuously Operating Reference Stations (CORS) via NGS’s Online Positioning User Service (OPUS), and relies on a time-dependent gravimetric geoid model. This method of accessing the NSRS is a paradigm shift from accessing NAD 83 and NAVD 88 through the direct occupation of geodetic survey marks.

GRAV-D is the project that collected airborne gravity over the entire United States (which was then used in the creation of the time-independent component of GEOID2022 [called the static geoid model of 2022 SGEOID2022, which represents the geoid at 2020.00]). GEOID2022 defines the zero-orthometric-height surface of the North American-Pacific Geopotential Datum of 2022 (NAPGD2022). NAPGD2022 will replace all existing vertical datums.

Yes. NGS has updated, and will continue to update, NADCON and VERTCON, and make both available through the NGS coordinate Conversion and Transformation tool (NCAT). At the roll-out of the modernized NSRS, NCAT will be updated and users will be able to transform between any NGS-defined historic datum and the new datums.

The WGS84 frames are not defined by NGS, and therefore are not supported within NADCON and VERTCON. However, NGS will provide, through NCAT, a new tool that allows for 14-parameter Helmert transformations between various reference frames (including the various WGS84s).

The NADCON and VERTCON tools contain significantly more information than 14-parameter Helmert transformations, and the proper integration of all these tools within NCAT requires some subtle and complex logic, to which users will have access in NCAT.

The coordinates of a mark on a datasheet will be epoch-dependent.

On the new “datasheets” (which we refer to as part of a “data delivery system” or DDS), NGS will publish two types of epoch-dependent coordinates: survey epoch coordinates (SECs) and reference epoch coordinates (RECs).

SECs will reflect coordinates, specifically at the epochs when a survey instrument occupied the point. These coordinates will be available in all four NSRS reference frames and ITRF2020, and NAPGD2022 for all points.

RECs will reflect coordinates that have been estimated through a least-squares adjustment where all observations have been projected through time to a reference epoch (the first being 2020.00) and then constrained to the NCN and IGS network.

Through a concerted outreach effort by NGS, each state had the opportunity to update their State Plane Coordinate System zones, with the roll-out of the four new terrestrial reference frames. Details on the process is available on the Current Policy for SPCS2022 web page. That page includes SPCS2022 policy and procedures, forms, and examples. Additional information about State Plane is also available, including documents and webinars, preliminary zone designs, and coordinate conversion utilities.

NGS has worked with the FEMA to determine the new vertical datum’s impact to DFIRMs, and this coordination will increase closer to the roll-out of the new datums. Specifically, NGS completed a pilot project with FEMA in 2010 to determine the impact of the new geopotential datum on floodplain mapping in North Carolina. You can read the report from this pilot project online. NGS will also coordinate with federal partners (e.g. FEMA) whose products or services (e.g. DFIRMS) may be impacted by the new datums through the Federal Geodetic Control Subcommittee and its working groups.

NGS regularly communicates with the USGS regarding its 3DEP, and this coordination will increase closer to the roll-out of the new datums.

OPUS-Share solutions will not be supported in the modernized NSRS. This reflects a correction to the primary flaw that has existed since NGS stood up this service. That flaw is that OPUS-Share was never integrated with the official coordinates of points in the NSRS, which are solely stored in the NGS integrated database (NGS IDB). The existence of OPUS-Share solutions provides numerous official-looking reports of the coordinates of points in the NSRS, where each such shared solution can disagree with others shared solutions, and all of them can (and often do) disagree with the official coordinates of the point as stored in the NGS IDB. To correct this flaw, NGS will only provide official coordinates (RECs or SECs) in the modernized NSRS that NGS has computed from user-contributed data, and which have been stored in the new NSRS database.