The document discusses how the USGS's geospatial datasets and services will be affected by the modernization of the National Spatial Reference System (NSRS). It notes that elevation datasets associated with 3DEP will be most impacted. Preparations include requiring machine-readable coordinate systems and messaging support for GPS on benchmarks. There is excitement about improved geoid and datum models aligning better with global systems. However, there is also concern about the challenges of transforming vast existing NAD83 datasets, such as 11 trillion lidar points. Key needs are the NADCON8 transformation tool and its incorporation into various software.

1. Feedback on NSRS Modernization
GIS in the Rockies
September 19, 2018
Turning Towards the Future
Joshua D. Nimetz
U.S. Geological Survey

2. Our major products/services/activities which will be affected by
NSRS modernization:
• National Geospatial Program Datasets
• Primarily those finer spatial resolution elevation datasets
associated with 3DEP
• Effect on coarser spatial resolution datasets associated with U.S.
Topographic Map products and National Hydrography Datasets less
significant
Our preparations to date include:
• Requiring machine-readable coordinate reference system information with
established EPSG codes for source elevation data
• Messaging support for GPS on BM (rounds 1 and 2) to our 3DEP contractors!
• Proving 3DEP elevation raster and vector products spanning geographic extent
of the U.S.A. and outlying territories to NGS for testing datum transformation
application
Preparation

3. We are excited because...
• Geoid2022 & NAPGD2022 – most accurate and reliable geoid height model and
orthometric datum yet!
• Transition to global reference frame with respect to plate tectonics will provide
much closer alignment to existing global navigation satellite system
• Mitigates reliance on current datum transformations from GNSS →
NAD83…
We are concerned because...
• Prospect of transforming existing NAD83 datasets is daunting
• 3DEP airborne lidar data holdings = 11 trillion points and growing…
• Multiple raster and vector datasets as well
• Possible alignment issues with legacy datasets
Advantages / Challenges

4. The tools, products, or services we need most
(from NGS or others) are:
• NADCON8
• Incorporation of NADCON8 into various transformation engines
The outreach we need most (from NGS or others):
• Please work with software vendors to incorporate NADCON8
Transition Tools / Outreach Needs