National Geodetic Survey

NOS Fiscal Year 2017 Year in Review

NGS Hosts 2017 Geospatial Summit

The National Geodetic Survey (NGS) hosted a 2017 Geospatial Summit in Silver Spring to provide updates regarding its planned modernization of the National Spatial Reference System (NSRS). NGS geodetic advisors and field personnel from across the country were on hand, as well as constituents from the U.S. Army Corps of Engineers, the National Society of Professional Surveyors, the Federal Emergency Management Agency (FEMA), and other federal, state, public, and private-sector stakeholders. Among the innovations discussed were the future of coastal mapping and the new tools NGS is working on to change the way it does business in the future.

GRAV-D Optionally Piloted Inaugural Flight

Operating Aurora Centaur optionally-piloted aircraft from console.  Credit: NOAA

Operating Aurora Centaur optionally-piloted aircraft from console. Credit: NOAA

In spring 2017, the National Geodetic Survey (NGS) completed the first operational survey on the Aurora Centaur optionally piloted aircraft for the Gravity for the Redefinition of the American Vertical Datum (GRAV-D) project. The survey operated for approximately one month out of Winston-Salem, NC, and collected data primarily over western North Carolina and eastern Tennessee. Following successful completion of Phases I and II of a Small Business Research Innovation effort, the optionally piloted survey demonstrated the aircraft’s potential to improve GRAV-D surveying efficiency and data quality while decreasing overall project costs. NGS’s GRAV-D project is collecting airborne gravity data to support more accurate height measurements for the nation. GRAV-D is estimated to provide $522 million in annual benefits to the nation once completed, with an estimated $240 million in annual benefits resulting from improved floodplain management.

NGS Completes 2017 Geoid Slope Validation Survey Field Observations

The Geoid Slope Validation Survey of 2017 (GSVS17) is the final of three validation surveys the National Geodetic Survey conducted to ground truth the results of its larger Gravity for the Redefinition of the American Vertical Datum (GRAV-D) project. The goal of GRAV-D is to update the U.S. vertical reference frame by 2022. To accomplish that goal, GRAV-D is conducting aerial gravity surveys over the entire U.S. to determine the “geoid model”—a model used as the zero-elevation surface for height measurements. The goal of GSVS17 is to prove, in incontrovertible scientific analysis, that the one-centimeter accuracy goals of GRAV-D are achievable, and that the full projected economic benefits of GRAV-D are attainable. The GSVS17 survey line extends approximately 223 miles, from Durango to Walsenburg, Colorado. Field observations conducted for the project included geodetic leveling, GPS, terrestrial gravity, and astrometric surveys. Data collected from GSVS17 will be used to evaluate and improve the accuracy of a new geoid model.

Florida Keys LIDAR Survey

The National Geodetic Survey (NGS) supports NOAA’s Integrated Ocean and Coastal Mapping (IOCM) approach to “map once, use many times” by planning and coordinating with multiple parties interested in using topographic-bathymetric (topo-bathy) LIDAR data. One example is NGS’s Key West and Florida Keys Outer Reef surveys. These datasets were collected to support the U.S. Coast Guard fleet’s navigational safety and the Office of Coast Survey’s (OCS) need to update charts in the region, which includes NOAA’s Florida Keys National Marine Sanctuary. Many of these areas are in dire need of new surveys, as some were last surveyed between 1900 and 1930. NGS processed and delivered 258 square nautical miles of topo-bathy LIDAR data for Key West and the Keys outer reef area to NOAA’s Digital Coast for IOCM purposes. OCS will use the data for application to NOAA nautical chart products. NGS’s LIDAR sensor reached up to 18 meters’ depth along the outer reef, and for the first time, resolved some imprecisely positioned charted dangers. NGS is able to survey nearshore areas where it is either inefficient or unsafe for NOAA hydrographic vessels to do so.