World Hydrography Day 2025: Everything To Know About Date, Origin, Significance And More

World Hydrography Day is observed every year. This year, the significant day will be observed on Saturday, 2025. The day aims to raise awareness about hydrography and its contributions to marine navigation, coastal development, disaster management, and environmental protection.

This day also recognises the importance of hydrography, which is the science of measuring and describing the physical features of bodies of water, like oceans, seas, rivers, and lakes.

What is Hydrography?

Hydrography is a graph that measures the depth of water bodies and how much water flows in a river or stream changes over time. A hydrograph analyses the volume of water flowing past a particular point per unit of time on the vertical and horizontal axes.

The part of the graph that shows the increase in water as water from rainfall or other sources enters the rivers or other water bodies. The highest point on the hydrograph indicates the maximum rate of water flow. If the graph shows a decrease in water flow, that means the river returns to its normal level.

About World Hydrography Day

World Hydrography Day is celebrated annually. This day is recognised to emphasise the significance of mapping and exploring water bodies. The day also promotes the public's understanding of hydrography science.

World Hydrography Day history

World Hydrology Day was established to acknowledge the vital role of hydrography in ocean governance and maritime safety. The day was specifically commemorates the founding of the International Hydrographic Organization (IHO) in 1921. The IHO was initially formed as the International Hydrographic Bureau. The United Nations officially recognised World Hydrography Day in 2005.