The objective of the Water Resources Programme is to provide Member States with science-based information and technical skills to better understand and manage their water resources.

Meeting the Challenge

Aspirations for development in many parts of the world are intricately linked to water. Whether concerning issues of health, food and agriculture, sanitation, the environment, industry, or energy production, a paramount issue in the 21st century is water - its availability, quality and management. The IAEA, through its Water Resources Programme, is one of the UN agencies responding to its Member States by providing science-based information and technical skills to improve understanding and management of their water resources.

Solutions through Science

To address global water challenges, such as water shortage and quality, over-exploitation and impacts of climate change on water resources, Member States need precise information to enable them to make decisions about sustainable water resource management. The journey of water from the ocean through the atmosphere, biosphere, to the Earth and back, is commonly known as the hydrological or water cycle.

A comprehensive understanding of this as well as that of hydrological systems such as river basins, lakes, and aquifers is essential to make resource development possible without having an adverse impact on the environment. Determining the 'fingerprints' of water and thereby understanding characteristics such as its source, movement, rate of recharge, pathways etc. is a key aspect of the scientific discipline known as Isotope Hydrology.

Undertstanding the Basics of Water

Atoms of an element with different mass are called isotopes. Water consists of isotopes of hydrogen and oxygen, which are distributed by natural processes throughout all segments of the hydrological cycle. The journey made by each drop of water causes it to undergo small, important and measurable changes in the relative abundance of the different isotopes. Therefore, water in different environments develops characteristic isotopic labels or 'fingerprints' that allow it to be distinctly identified from water in other environments. This make it possible, for example, to trace the source of the water or to estimate how long a body of water has been in the hydrological system.

Tools to Unlock Water's Secret

Nuclear Science has developed an array of methodologies and analytical techniques which use various isotopes of water to characterize water masses and trace their history and movement through the hydrological cycle. The IAEA's Water Resources Programme has been pioneer in developing isotope hydrology as a powerful and effective scientific approach. By tracking the isotopes of water, scientists can quickly obtain valuable information which otherwise may require decades of hydrological data collection.

Isotope techniques can help determine the origin, age and renewal rate of groundwater, and whether it is at risk of salt water intrusions or contamination. It also permits the rapid and reliable mapping of non-renewable groundwater resources, the majority of which are transboundary aquifers, so that they can be abstracted rationally for equitable use. Isotope techniques are important tools to understand surface water movement and inter-action with groundwater, dam leakages, and the impact of climate change on water resources development and management.

Working for Member States

The IAEA works with Member States to adapt and apply isotope techniques to the needs of each country. From technical advice and analysis to capacity building and expert services, the Water Resources Programme is ready to support Member States in addressing their water resource management issues. While helping to test and adapt various techniques under a variety of hydrogeological conditions, the experts from the Water Resources Programme strive to develop the scientific approaches through applied research.

Responsible/Contact: Isotope Hydrology Section | Last update: 04 March 2010