Niue, MBES Bathymetry Survey Technical Report (Er049)

This report describes a high-resolution bathymetric mapping survey of the seabed surrounding the island of Niue. The survey was carried out over a period of six days in May 2005, resulting in the acquisition of over 550 km of multibeam echosounder (MBES) data.
This report describes a multibeam bathymetry survey of the seabed surrounding the island of Niue and report is available for download from its approprite link under Distribution Info.
This work was initiated by the SOPAC/EU project "Reducing Vulnerability of Pacific ACP States".The purpose of this project is to provide a comprehensive GIS database containing information relating to three sectors of interests: aggregates for construction, water and anitation, and risks and hazards. Seabed maps are of potential use for all three sectors, and consequently are a major activity within the project. With this in mind, the objective of the marine survey was to produce maps of the seafloor topography around the island of Niue using a multibeam echosounder (MBES).Niue is located 19°03’S and 169°52’W. Approximately 430 km east of Location Vava’u, Tonga, and 520 km southeast of American Samoa.The survey achieved 100 % coverage of the seafloor from approximately 50 m depth in the nearshore area to an average offshore distance of 5 km, reaching water depths of some 2000 m. The seafloor terrain was found to be highly irregular with an average slope of A review of external sources of available bathymetry was also undertaken, and the survey data was supplemented with publicly available data for Niue EEZ. The resultant data compilation was used to produce bathymetry charts of Niue at a scale of 1:50 000, and a more detailed chart of Alofi Bay at a scale of 1:10 000. These new bathymetric maps give a descriptive picture of the ocean bottom terrain, vividly revealing the size, shape and distribution of underwater features, and serve as the basic tool for scientific, engineering, marine geophysical and environmental studies, as well as marine and coastal resource management.