RTK GPS horizontal and vertical positioning of vessel
Upon the early introduction of RTK GPS positioning Arc realized the advantages this technology would have in the ability to more accurately measure the horizontal position and possibly, some day, the vertical position of its hydrographic surveying platforms. Today this technology is proven and has become commonplace with the everyday hydrographic operations at Arc for both horizontal and vertical positioning of its vessels. The firm has successfully utilized the Jacksonville Districts in-place RTK Networks for hydrographic surveys within the St. Mary’s Entrance Channel, servicing the U.S. Navy’s Kings Bay Nuclear Submarine Base (See below image). Arc utilizes the GPS/RTK system at many locations, including Jacksonville Harbor St Johns River Surveys, Cape Canaveral Port and Tampa Bay. In addition, Arc’s hydrographers utilize the technology in establishing project dependent Hydrographic RTK GPS Networks which in turn transmit GPS differential corrections to our survey vessels. Arc is familiar and experienced in acquiring the correct GEIOD parameters and generating HYPACK KTD files required in accurately generating Real Time Water Surface or Tide Corrections at the vessel. This ability allows for the measurement of the water surface at the origin of the sounding and is not influenced by current, wind and seas between the survey vessel and historical distanced shore mounted conventional tide staffs.
During 2016 and 2017 Arc performed a 92-square mile multibeam survey at Naval Submarine Base Kings Bay Georgia under contract to Versar/AECOM. The survey purpose was to study sediment movement in the estuary in order to determine potential solutions to shoaling in the St Marys Entrance Channel to Kings Bay Naval Base. Horizontal and vertical positioning of the survey vessels on this project were accomplished utilizing the Jacksonville District ACOE GPS/RTK network.