Water is essential to sustaining life on earth and is also the basis of millions of jobs. This year’s theme for World Water Day — better water, better jobs — links how the quantity and quality of water can change workers' lives and livelihoods, and even transform societies and economies. Nuclear science and technology can help protect water, which in turn can help protect livelihoods.
“Water is a finite, yet renewable resource. Understanding the dynamics of water systems is essential to increasing its availability and securing its sustainable future,” said Pradeep Aggarwal, Head of the IAEA’s Hydrology Section. “Nuclear science and technology can help gather the data needed to build effective water management policies and regulatory frameworks, which ultimately impacts people’s lives.”
71% of the world’s surface is water, but 98% of the earth’s freshwater is buried underground. This underground water, or groundwater, is a vital resource for supplying drinking water and the water needed in agriculture, industry and tourism. It is the source of half of all irrigation water used to grow the world’s food and accounts for around a third of total global water withdrawals. However, many groundwater resources are poorly understood and are threatened by shortages, pollution and over-extraction.
The IAEA supports countries in using naturally occurring isotopes — atoms with a different number of neutrons — to understand the dynamics of the water system. Through isotopes, scientists can track the water molecules along their path through the water cycle: from evaporation, precipitation, infiltration, runoff, evapotranspiration and return to the ocean or to the atmosphere. The water molecules’ ‘fingerprints’ reveal key facts about the water’s status, from the rate at which an aquifer is recharged, to how long water remains in the aquifer, to its path from the surface to the ground or its vulnerability to pollution. This enables scientists to gather information about water replenishment rates, flow, and vulnerability to pollution, as well as to determine water’s age, origin, quality, and quantity.
See how scientists, policy makers, and officials teamed up in Brazil, Argentina, Paraguay and Uruguay to use these techniques, with IAEA support, to help them protect and sustainably use their shared water resource, the Guarani Aquifer — the largest groundwater reservoir in Latin America. Watch this video on how the IAEA promotes the use of nuclear techniques to tackle water challenges.
Optimizing water use
In many parts of the world, water is scarce. With climate change bearing down, environmental conditions become harsher and drought occurs more frequently, amplifying this scarcity. Finding the right balance in water conservation and use in these areas of the world is essential to maintaining human life and for growing the crops and caring for the livestock that serve as a source of income and food for many.
Isotopic techniques offer a way to strike that balance by helping in uncovering important clues in soil and water for optimizing water use. They provide an insight into evaporation rates, how much water plants use, and the moisture level in the plants and soil. This information has helped more than 300 farmers in Kenya, where more than 80 per cent of the land is arid or semi-arid, to improve their water use and crop output.
In Mauritius, small-scale farmers who rely heavily on rain to grow crops are benefiting from a method called drip irrigation, which, when combined with the data gathered using isotopic techniques, allows them to carefully optimize water distribution, leading to a boost in farmer incomes as well as the local agricultural and tourism industries. Read about Manoj Chumroo, a farmer from eastern Mauritius, who has benefited from an IAEA project involving this method and in what kind of ways his life has changed.
Water and sustainable development
The demand for water will only increase as populations continue to grow and economies expand. The international community underscored the central role water plays and the critical importance of its effective management when countries committed to ensuring the continued and sustainable access to clean and safe water as one of the 17 goals of the United Nations Sustainable Development Goals (SDGs) adopted in September 2015. The IAEA supports these aims by bringing science, technology and innovation to water management.
“The stewardship of water resources is held in common by all nations, and sustainable management requires levels of cooperation and collaboration never before achieved,” said Aggarwal. “We cannot underestimate the importance of water. By working together, we can continue to ensure its continued supply and to help in realizing this sustainable development target.”
We cannot underestimate the importance of water. By working together, we can continue to ensure its continued supply and to help in realizing this sustainable development target.