Regulation 9 - Hydrographic Services


  • Contracting Governments' obligations for providing hydrographic services.
Regulation 9

Contracting Governments undertake to arrange for the collection and compilation of hydrographic data and the publication, dissemination and keeping up to date of all nautical information necessary for safe navigation.



In particular, Contracting Governments undertake to co-operate in carrying out, as far as possible, the following nautical and hydrographic services, in the manner most suitable for the purpose of aiding navigation:

2.1 to ensure that hydrographic surveying is carried out, as far as possible, adequate to the requirements of safe navigation;
2.2 to prepare and issue nautical charts, sailing directions, lists of lights, tide tables and other nautical publications, where applicable, satisfying the needs of safe navigation;
2.3 to promulgate notices to mariners in order that nautical charts and publications are kept, as far as possible, up to date; and
2.4 to provide data management arrangements to support these services.



Contracting Governments undertake to ensure the greatest possible uniformity in charts and nautical publications and to take into account, whenever possible, relevant international resolutions and recommendations.*


4. Contracting Governments undertake to co-ordinate their activities to the greatest possible degree in order to ensure that hydrographic and nautical information is made available on a world-wide scale as timely, reliably, and unambiguously as possible.

* Refer to the appropriate resolutions and recommendations adopted by the International Hydrographic Organization


MCA Guidance
1. Contracting Governments are required to cooperate in compiling and propagating hydrographic data and providing services, which include adequate hydrographic surveying, issuing of charts and nautical publications and promulgating notices to mariners. They must provide data management for these services.

Emphasis is placed on uniformity, and on compliance with the resolutions, standards and recommendations of the International Hydrographic Organization (IHO). Nautical charts are, and will remain, the most important aid to safe navigation. The requirement for accurate and up to date charting, especially of coastal areas, cannot be over emphasised. This need is underlined in the IMO Circulars MSC/Circ. 1118 and MSC/Circ. 1179, which also highlight areas of the world currently not surveyed to the required standard.

3. In the UK, the Committee on Shipping Hydrography (COSH) advises on the hydrographic survey priorities of the UK Civil Hydrography Programme (CHP) to ensure that the UK waters are surveyed to modern standards. The CHP is administered by the MCA. The parent Civil Hydrographic Review Committee (CHRC) sets the survey priorities and approves the expenditure. The MCA has a Memorandum of Understanding with the UKHO, which covers the preparation, publishing and updating of hydrographic products in UK waters and the provision of the national co-ordinator for navigational warnings.

Mariners are requested to inform the UKHO immediately when new dangers or changes / defects in aids to navigation are identified. Full contact details and instructions, together with copies of the UKHO reporting form (Hydrographic Note-H.102) are provided in the weekly edition of the Admiralty Notices to Mariners.

Hydrographic Notes can also be downloaded and submitted electronically through the UKHO website -

Notices to Mariners can be found on the UKHO's searchable website at

Notices to Mariners Website:
Fax: +44(0)1823 322352
Tel: +44(0)1823 723315

Urgent navigational information - e-mail:

Other navigational information - e-mail:

See also:

MSC/Circ. 1118 - Implementation of SOLAS Regulation V/9 - Hydrographic Services Services and

MSC/Circ. 1179 - Deficiencies in Hydrographic Surveying and Nautical Charting Charting.


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