IHO releases new standards for hydrographic surveys

By clarifying the required levels of accuracy, they will help define the requirements in terms of technology, time and human resources and will save valuable resources.

One of the notable changes in this latest version is the introduction of a new more stringent classification for surveys called “Exclusive Order” which expands the standards' applicability. This is designed for specific critical areas such as harbours and channels with minimum underkeel clearance and bottom characteristics which could be hazardous to vessels. In these specific areas, an increased accuracy of +/- 10 cm on a map can help precisely determine requirements for dredging and avoid unnecessary costs.

Another key feature of this edition is a new “Specification Matrix”, a matrix of parameters and data types which defines the required accuracy depending on the hydrographic needs. The aim is to allow flexibility in the survey definition and to accommodate these various needs as well as emerging technologies such as satellite derived bathymetry.

“S-44 is the hidden champion amongst IHO´s technical standards”

Dr Mathias Jonas, IHO Secretary-General

“It is regarded as the reference for any contracted survey and provides the benchmark for the validation of results”

Since the cost of surveys can range in the millions of Euros, S-44 is an essential tool for all institutional and commercial surveyors.

S-44 specifies the minimum standards to be achieved depending on the intended use. Hydrographic offices and organisations are able to define more stringent or specific requirements for national or regional variations when necessary. For procedures for setting up equipment, conducting surveys, and processing the resulting data, users can refer to the IHO Manual on Hydrography (Publication C-13).

“This new edition is not a revolution, but represents nonetheless a real evolution and is a logical next step incorporating feedback we received from the hydrographic community and IHO stakeholders”

Christophe Vrignaud, Shom

Christophe Vrignaud of the French Hydrographic office (Shom), led the Hydrographic Surveys Project Team (HSPT) which had been tasked with updating the standards.  

The title of the 1st edition of S-44 which was published in 1968 was “Accuracy Standards Recommended for Hydrographic Surveys” and still highlights to this day the main focus of the standard. The IHO has endeavoured to update it regularly to keep pace with new technology and methods.