Virtual Water and the Impact of the Global Water Trade

Jun 20

There is an invisible force at play. A thirst that travels unseen. Millions of liters of water. Embedded within the things we buy, the clothes we wear, the food we eat. Virtual water is the staggering amount of water used throughout a product's life cycle, from the cradle of raw materials to the final product in your hands.

What are direct and indirect water use? Direct water use refers to the water we see and use explicitly, like tap water for drinking or irrigation in agriculture; however, the water used to grow those crops we irrigate isn't directly visible. Indirect water use, also known as virtual water, refers to the hidden water used throughout the entire lifecycle of a product or service. This concept captures the total volume of water consumed from initial raw material extraction to the final product reaching the consumer.

The worldwide virtual water trade involves the exchange of goods and services that carry embedded water. This trade allows water-scarce countries to import water-intensive products, thereby conserving their own water resources. The United States exported around 412 million liters of water in 2022. Importing one tonne of wheat can save a water-scarce country about 1,300 cubic meters of water that would have been used if the wheat were produced domestically. Countries like Saudi Arabia, 95% desert, import these water-intensive crops. You can see how this is very beneficial to countries low on resources. On the other hand, countries like the United States and China are major exporters of virtual water through their agricultural products.

This might seem all fine and dandy but exporting water comes with significant risk. Countries heavily on exporting water-intensive crops can lead to excessive groundwater pumping, depleting local water reserves. Communities and ecosystems that rely on this water are forced to migrate from the impending drought but what if we reach a point where we can't get away from it? Large-scale farms established for export can displace local farmers and disrupt traditional practices. Unsustainable agricultural practices used to maximizing yields can inadvertently damage the environment through soil erosion, salinization, and pollution, ultimately reducing the land's ability to produce food in the long run.

Check out this video! It does a great job of explaining the virtual water trade.

The Aral Sea in Central Asia serves as a cautionary tale. The Aral Sea relied on water from two main rivers, the Amu Darya and Syr Darya. The Amu Darya is considered the longest river in Central Asia. It originates in the Pamir Mountains, which border Tajikistan, Afghanistan, and China, and flows northwestward into the remains of the Aral Sea. The Syr Darya originates in the Tian Shan mountains in Kyrgyzstan and eastern Uzbekistan and flows westward, eventually reaching the northern part of the Aral Sea as well.

These rivers were diverted for large-scale cotton production, particularly in Uzbekistan. Cotton is a very thirsty crop, requiring a lot of water to grow. On average, it takes around 1,931 liters of irrigation water to produce 1 kilogram of cotton lint (roughly the amount for a t-shirt and a pair of jeans). This is combined with an additional 6,003 liters of rainwater on average.

Estimates suggest the rivers have shrunk by around one-third in volume compared to their historical levels. his shrinkage has happened relatively rapidly, occurring over a period of just 70 years or so. With so much water diverted, there wasn't enough left to reach the Aral Sea, causing it to shrink dramatically.

Uncontrolled water exploitation has severe consequences. Social unrest and economic hardship become inevitable. Displaced communities face the challenge of finding new homes and livelihoods. This puts a strain on already stressed regions with limited resources. The psychological impact is profound. People experience a deep sense of loss for their ancestral lands and fear for the unknown future. Water scarcity is not just an economic issue; it threatens the very foundation of modern civilization and the environment in which we live.