Save water supplies
Our world is unique. It is the only known planet with surface water, and where there is water there is life. Life sprang from water, everything that lives is largely water – and without water we cannot survive long. Seventy percent of the Earth’s surface is covered by immense oceans – enough water for everyone, it seems. Yet we are on the brink of a global crisis. The lives of billions of people and animals are threatened by an increasing demand for water.
How much water?
There is plenty of water in the world, but less than 3% of it is freshwater, and living things need clean freshwater. Of that 3%, we can use less than half a percent, the rest is frozen in glaciers and ice caps at the Arctic and Antarctic, or deep in the Earth’s crust. Some scientists have proposed extracting the salt from seawater, and many places have desalination plants. But this technique produces little fresh water and consumes a lot of energy. Deserts and other hot, dry places clearly suffer from a water shortage. The water requirement also exceeds availability elsewhere. Only through the construction of complex pipe systems can cities and agriculture continue to be supplied with water from other areas.
Over the past century, global water consumption has increased tenfold, and the limit has been reached in many places. It is estimated that the world’s population will double in 30 years, and water scarcity is predicted to be a global problem in 20 years. Millions of people already die every year from ailments such as diarrhea because they have no access to clean water. If the demand for water continues to rise, these millions of deaths could reach billions.
Water shortages can also lead to the death of millions of animals and crop failures. Agriculture is already largely dependent on water: to grow one orange you need as much as 500 liters of water.
The demand for water
If water were only needed for drinking and washing, there might be enough available. However, the developed world uses enormous amounts of water for other purposes. Of the 1,500 billion later freshwater used daily in the United States, most goes to farmers, and to power plants that use it to cool electricity generators. Only 1% is accounted for by ‘normal’ households. As demand for water rises worldwide, efforts to meet that demand are starting to take their heavy toll. Because the water has to be taken from hard-to-reach places and pumped via pipe systems over ever greater distances, the delivery costs rise sharply. There is also a real danger of conflict situations if states have to compete for scarce water resources.
The growing demand for water can also have profound consequences for our environment. Many rivers, lakes and wetlands are being destroyed by increasing water abstraction and being contaminated with industrial, agricultural and urban waste. Pollution affects all life: pesticides in the water, for example, can poison animals. The biodiversity (the variety of species within a natural environment) in freshwater is declining and is worse than in other ecosystems such as forest areas, grasslands and coastal areas. Many of the freshwater animal species are in danger of extinction. Some directly endangered species are: the Atlantic sturgeon, the river dolphin, the tapir, and birds such as the Siberian crane. Many take water for granted, but it is our most valuable resource. If we want to secure the future of our planet, we must act now.