Industrialisation and the subsequent explosion of population during the 1800s marked the start of major shortages, and by the turn of the 20th Century about 2% of people experienced 'chronic' water shortage. By 1960, this number had risen to 9% (280 million people) and by 2005 it affected a staggering 35% of the world's population (2.3 billion people).
In some areas, water is becoming as valued as oil and some predict it to be a major source of conflict and war in the 21st Century and beyond. Unfortunately, things may be about to get worse. Recently, research has indicated that climate change will seriously impact water availability and this, when coupled with our rapidly rising population, makes water supply one of the most serious challenges facing human development.
Current Water Shortages
According to water.org there are 3.4 million deaths each year - 99% of which in the developing world - caused by water-related diseases. There are 780 million people who lack access to clean water and a five minute shower will use more water than the average slum-dwelling person will use in an entire day.
Whilst water scarcity is most severe in the developing world, it is not absent from developed economies either. As you can see below, Australia, Spain, Portugal and Japan are under 'high stress' and the UK, China and Argentina, among others, are experiencing 'medium to high stress'. 60% of European cities where the population exceeds 100,000 are using groundwater faster than it can be replenished. Even the UK, which contains some of the wettest areas in Europe, suffers from mild drought once every 5-10 years.
The amount of water we consume day-to-day is surprising. Taking a long shower and watering your garden may seem wasteful but it uses a lot less water than what's on your dinnerplate. Domestic water use represents about 10% of total freshwater use, with industry taking 20% and irrigation for agriculture a whopping 70%. The environmental impact of providing all of this water for irrigation can be huge; as was explored on ClimateReach in an article about the rapid decline of the Aral Sea.
Food takes an incredible amount of our water budget. It is estimated that eating a single banana requires 160 litres of water to produce. Drinking a litre of beer takes nearly 300 litres to make and a single cup of coffee needs about 130 litres of water; the equivalent of running a well-filled bath.
Meat is the most water-intensive products we regularly consume. Chickens took 11% of all the world's farming water between 1996 and 2005 and costs 4,330 litres of water for every kilogram of meat produced. However, the most water-expensive product is beef, a single kilogram of which costs 15,400 litres of water. Of course, 99% of this figure represents food for the cow itself and much of this is eventually recycled back into the water cycle. Despite this, the total water cost of a kilogram of your Sunday joint is the equivalent of taking 154 baths.
Unfortunately, our wastage of water is massively compounding the problem. Just by throwing away food the world wastes about 1,380 cubic kilometres of water each year - the equivalent of half of Lake Victoria (Africa's largest lake). On a personal scale, leaky taps and pipes costs the average US citizen nearly 40,000 litres of water - or about 10% of their annual water bill.
The Future
Fresh water is a renewable resource, but the rate at which it is renewable can vary with climatic shifts. A general rule-of-thumb is that climate change is likely to make wetter areas wetter and drier areas drier. A warmer atmosphere can retain more moisture; a result of the effect temperature has on evaporation and condensation. Despite our solid understanding of thermodynamics, modelling this relatively simple statement to see what happens to the climate is challenging due to the complexity of our climate system and the sheer size of the Earth. However, a study published this week concluded that climate change may not directly cause droughts, but could make them more sudden and more intense.
In terms of people affected, a recent study estimates that if warming exceeds 2°C above present 15% of the global population will have 'severely decreased' access to water resources. In addition, it could put 40% more than population growth alone into 'absolute water scarcity' (<500m3 per capita per year). The authors conclude that 'climate change is likely to exacerbate regional and global water scarcity considerably'. It is easy to see why; consider that many of the Asia's largest rivers - the Ganges, Yangtze, Mekong, Yellow to name a few - are sourced from Himalayan glaciers. There are fears that retreating glaciers may endanger water resources for the 2.4 billion people that live, and are sustained, by these waters downstream.
Although there are uncertainties over the future of precipitation patterns and drought intensities, there is no denying that our water needs will increase. The UN predicts that population rise will increase annual water demand by 64 billion cubic metres and by 2030 they expect 47% of people to live under high water stress.
The Solution
A solution is easy to think up but difficult to implement. Less wastage and more supply are the most obvious steps to take. As is developing water-efficient technologies and investing in more infrastructure, especially in developing nations.
However, no amount of money can solve the problem if there simply isn't the supply. Luckily, there may be a new source of supply far larger than previously thought. A new research paper published in Nature suggests that vast reserves of low-salinity water are understood to be trapped under the seabed on continental shelves. The amount extractable may be more than 100 times greater than the water we have already extracted from below ground since 1900. These aquifers formed when rain water fell onto the continental shelf when sea-level was much lower. Layers of clay and sediment trapped this water and prevented it from being washed-out when sea-levels rose again following deglaciation 20,000 years ago. Although it is likely to be 'brackish' (slightly saline), the cost of treating this water to make it drinkable will be far less than treating salty seawater.
This supply is not without its problems and would be a technical and economic challenge to extract; requiring rigs akin to oil wells, large treatment plants and a vast network of pipes or vehicles to transport the water. Moreover, once the supply is gone, it's gone. It is very much a non-renewable resource. Nevertheless, in a world becoming increasingly short on what is arguably our most vital resource, these aquifers may become a life-line for future generations.
According to water.org there are 3.4 million deaths each year - 99% of which in the developing world - caused by water-related diseases. There are 780 million people who lack access to clean water and a five minute shower will use more water than the average slum-dwelling person will use in an entire day.
Whilst water scarcity is most severe in the developing world, it is not absent from developed economies either. As you can see below, Australia, Spain, Portugal and Japan are under 'high stress' and the UK, China and Argentina, among others, are experiencing 'medium to high stress'. 60% of European cities where the population exceeds 100,000 are using groundwater faster than it can be replenished. Even the UK, which contains some of the wettest areas in Europe, suffers from mild drought once every 5-10 years.
The amount of water we consume day-to-day is surprising. Taking a long shower and watering your garden may seem wasteful but it uses a lot less water than what's on your dinnerplate. Domestic water use represents about 10% of total freshwater use, with industry taking 20% and irrigation for agriculture a whopping 70%. The environmental impact of providing all of this water for irrigation can be huge; as was explored on ClimateReach in an article about the rapid decline of the Aral Sea. |
| Irrigation accounts for 70% of freshwater use |
Meat is the most water-intensive products we regularly consume. Chickens took 11% of all the world's farming water between 1996 and 2005 and costs 4,330 litres of water for every kilogram of meat produced. However, the most water-expensive product is beef, a single kilogram of which costs 15,400 litres of water. Of course, 99% of this figure represents food for the cow itself and much of this is eventually recycled back into the water cycle. Despite this, the total water cost of a kilogram of your Sunday joint is the equivalent of taking 154 baths.
Unfortunately, our wastage of water is massively compounding the problem. Just by throwing away food the world wastes about 1,380 cubic kilometres of water each year - the equivalent of half of Lake Victoria (Africa's largest lake). On a personal scale, leaky taps and pipes costs the average US citizen nearly 40,000 litres of water - or about 10% of their annual water bill.
The Future
 |
| 15,400L of water produces 1kg of beef |
In terms of people affected, a recent study estimates that if warming exceeds 2°C above present 15% of the global population will have 'severely decreased' access to water resources. In addition, it could put 40% more than population growth alone into 'absolute water scarcity' (<500m3 per capita per year). The authors conclude that 'climate change is likely to exacerbate regional and global water scarcity considerably'. It is easy to see why; consider that many of the Asia's largest rivers - the Ganges, Yangtze, Mekong, Yellow to name a few - are sourced from Himalayan glaciers. There are fears that retreating glaciers may endanger water resources for the 2.4 billion people that live, and are sustained, by these waters downstream.
Although there are uncertainties over the future of precipitation patterns and drought intensities, there is no denying that our water needs will increase. The UN predicts that population rise will increase annual water demand by 64 billion cubic metres and by 2030 they expect 47% of people to live under high water stress.
The Solution
A solution is easy to think up but difficult to implement. Less wastage and more supply are the most obvious steps to take. As is developing water-efficient technologies and investing in more infrastructure, especially in developing nations.
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| Rigs similar to those that extract oil could one day be used to extract water. Source |
This supply is not without its problems and would be a technical and economic challenge to extract; requiring rigs akin to oil wells, large treatment plants and a vast network of pipes or vehicles to transport the water. Moreover, once the supply is gone, it's gone. It is very much a non-renewable resource. Nevertheless, in a world becoming increasingly short on what is arguably our most vital resource, these aquifers may become a life-line for future generations.
