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Nationwide Differential GPS (NDGPS)
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On April 18, 2008, the U.S. Department of Transportation approved a decision to continue the inland component of the Nationwide Differential Global Positioning System (NDGPS), which provides an accurate, highly-reliable, real-time GPS correction signal. The decision is based on the results of the NDGPS user assessment conducted by the Research and Innovative Technology Administration (RITA). RITA followed the plan announced in the Federal Register notice on NDGPS (72 FR 42219), assessing the current user needs and systems requirements for the inland component of NDGPS. The notice listed 10 factors for consideration. Information was gathered on these 10 factors through public responses to the notice (including responses from state and local governments, the private sector, and the non-profit sector), and through quantification of the mission requirements of other federal agencies using inland NDGPS. Discussions are ongoing regarding the future funding mechanism for inland NDGPS, and will be addressed in future budget submissions. This decision was endorsed by the National Space-Based Positioning, Navigation and Timing Executive Committee at their meeting of March 20, and publicly announced at the PNT Advisory Committee meeting on March 27. You may read the full NDGPS Assessment report.

Historically, the Department of Transportation (DOT) has sponsored the inland segment of the Nationwide Differential GPS (NDGPS) and provided funding to the Coast Guard for operation, maintenance, and construction of 29 operational, 14 caretaker, and 7 proposed sites. Because inland NDGPS is outside the Coast Guard’s statutory authority, this sponsorship is critical to continued operations of the system. The current sponsor is the U.S. Department of Transportation, Research and Innovative Technology Administration (RITA).

For FY12 budget year, DOT has requested an additional 7.6 million dollars in funding that will allow the inland NDGPS sites to upgrade equipment. The more robust equipment used at the U.S. COAST Guard and Army Corps of Engineers (ACOE) sites will allow greater value to our customers and lower repair costs. The long term DOT NDGPS goal is to proceed with the completion of Initial Operating Capability (IOC) of single coverage throughout the US and eventually provide Full Operating Capability (FOC) that will provide OCONUS dual coverage NDGPS for all to use.

Please direct any concerns for the future of the NDGPS program in writing to:

Timothy A. Klein
Senior Policy Advisor Research and Innovative Technology Administration
U.S. Department of Transportation
RTG-30, Room 3105
400 Seventh Street, SW
Washington, DC 20590

To date, the US Coast Guard monitors and controls 38 operational NDGPS sites that belong to the DOT. The Coast Guard is a key member of the seven-agency partnership for the Department of Transportation’s NDGPS expansion initiative. The Coast Guard brings its expertise in building, operating and maintaining DGPS sites to the partnership. The other members of the project are the U.S. Air Force, the U.S. Army Corps of Engineers, the Federal Highway Administration, the National Oceanic and Atmospheric Administration, the Office of the Secretary of the Department of Transportation, and most recently appointed sponsor for the project is the Research and Innovative Technology Administration (RITA).

NDGPS Program Update:

Major ongoing NDGPS projects include:

1. New NDGPS Sites

The following sites were approved to be constructed by the Policy Implementation Team to achieve Initial Operational Capability (IOC) in CONUS as funding permits. The preparations needed prior to construction of a proposed site include an Environmental Assessment (EA), a Formal Site Survey (SV), an Installation Design Package (IDP), and a Lease or Property Use Agreement.

  • Bliss (ID) - Pending construction funding.
  • Big Lake (TX) - Pending lease negotiations construction funding.
  • Carlsbad (NM) – Pending construction funding.
  • Marshall (TX) - Pending lease negotiations construction funding.
  • Patten (ME) - Pending construction funding.
  • Sage Junction (ID) - Pending construction funding.
  • Tucson (AZ) - Pending IDP and construction funding.
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