World Hydrography Day (WHD) is annually observed across the globe on 21 June to recognise the crucial role of hydrography in maritime navigation, environmental protection, and the sustainable development of marine resources.
- The day aims to raise awareness about hydrography, the science of measuring and describing the physical features of oceans, seas, coastal areas, lakes, and rivers.
- The annual observance of WHD is coordinated by the Monaco-based International Hydrographic Organization (IHO), an inter-governmental body responsible for promoting the proper surveying and charting of the world’s oceans, seas, and navigable waters.
Theme:
The theme of WHD 2025 is “Seabed Mapping: Enabling Ocean Action”, which highlights the critical role of hydrographic data in maritime safety, sustainable ocean governance, and climate resilience.
Background:
i.In 2005, IHO introduced the idea of observing WHD
ii.On 29th November 2005, United Nations General Assembly (UNGA) adopted a resolution A/RES/60/30 titled “Oceans and the Law of the Sea” and declared 21 June as World Hydrography Day.
iii.The first ever WHD was observed on 21st June 2006.
Why 21 June?
i.WHD is annually observed on 21st June to commemorate the establishment of the IHO, which was originally founded as the International Hydrographic Bureau (IHB) on 21st June 1921 to enhance global navigation safety through improved nautical charts and publications.
ii.The IHB was later renamed as the IHO in 1970.
2025 Event:
i.The 2025 West African Hydrographic Summit was held from 19th to 21st June 2025 at the Abuja Continental Hotel, Nigeria, alongside World Hydrography Day celebrations.
- Maritime professionals and organizations showcased hydrographic products and technologies.
ii.In South Africa (SA), naval events including lectures, book launches, and ship visits were conducted to educate the public on ocean mapping and hydrographic science.
Ex Abyssis ad Alta – IHO Award for Hydrographic Excellence 2025:
As part of World Hydrography Day 2025, the IHO announced Louis Maltais, Director, Navigation-Geospatial Services and Support at the Canadian Hydrographic Service (CHS) in Ottawa, Canada, as the recipient of the Ex Abyssis ad Alta Award for Hydrographic Excellence, recognising his key role in advancing Canada’s digital hydrographic services.
About Hydrography:
i.Hydrography is the science that deals with the measurement and description of the physical features of oceans, seas, coastal areas, lakes, and rivers, as well as the prediction of their change over time.
ii.It primarily focuses on supporting marine navigation, safety at sea, and the sustainable management of marine resources.
iii.It supports the implementation of international conventions such as the Safety of Life at Sea (SOLAS) Convention under the London (United Kingdom, UK) based International Maritime Organization (IMO).
iv.Provides critical data for climate change studies, coastal zone management, and marine ecosystem monitoring.
Indian Naval Hydrographic Department (INHD):
i.The INHD originated as the Indian Marine Survey Department, which was established in 1874 in Calcutta (now Kolkata), West Bengal (WB).
ii.It later became part of the Indian Navy(IN) and was eventually renamed as the INHD.
iii.The department is now known as the National Hydrographic Office (NHO) and is located in Dehradun, Uttarakhand. It is responsible for conducting hydrographic surveys and preparing nautical charts for India’s maritime zones.
v.It operates under the supervision of the Chief Hydrographer to the Government of India (GoI).
- Vice Admiral Lochan Singh Pathania, currently serves as the Chief Hydrographer to the (GoI).
About International Hydrographic Organization (IHO):
Secretary-General– Dr Mathias Jonas (Germany)
Headquarters– Monaco
Established – 1921
