Guidelines on Bathymetric Surveys in Danish Harbours

This page provides guidelines to Danish Harbour Authorities engaged in bathymetric data collection for improving safety of navigation and facilitating timely updates of official nautical products and services.

Standard Requirements for Bathymetric Surveys

The International Hydrographic Organization provides a standard (IHO S-44) that specifies the minimum requirements to be achieved for a bathymetric survey based on the intended use of the data. This standard addresses the vertical and horizontal accuracy as well as required coverage and feature detection necessary to achieve different quality levels.

IHO S-44 Special Order is appropriate for most harbour purposes. However harbours may specify the use of a higher (Exclusive Order) or lower (Order 1a) specification as appropriate, depending on how critical under keel clearance is and local conditions.

Quality Assessment

Harbour authorities will benefit from having high quality bathymetric data included in official nautical charts to support safety of navigation and higher demands for critical under keel clearances.

Bathymetric data in use by official nautical products are assessed based on:

  • The equipment used to acquire the data.
  • The procedures adopted to collect and process the data.
  • The qualified personnel that performed both data collection and processing.

These, along with a clear statement of the IHO Order (e.g. Special Order) which was achieved, must be documented and delivered along with the data.

Submission of Survey

In summary, the assessment of bathymetric data requires that the used equipment, the adopted procedures and the involved personnel are clearly documented. The Danish Geodata Agency strives to maximize the use of data for updating nautical products and services. The assessment of a survey’s quality (and how it may be used in updating products) is tied to the information provided in the submitted documentation. A submission form is available which helps structure both data and documentation and offers information on delivery to the Danish Geodata Agency.

Harbour authorities can facilitate the acceptance of harbour data collections into nautical products by ensuring the submission of all relevant documentation and data to the Danish Geodata Agency is part of the survey contract.

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