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Troubled waters

Water seems like the simplest of molecules, but its complexities have enabled all life on Earth. Its high specific heat capacity allowed early aquatic life to survive extreme temperature fluctuations, its ability to dissolve a wide range of compounds means it is used as a solvent for cellular compounds, and its powerful cohesive properties allow tree sap and blood to move upwards, against the flow of gravity.



ITV science correspondent Alok Jha discussed the incredible properties of water this week as part of a Cabot Institute and Festival of Ideas talk at The Watershed, Bristol.  This was part of a promotional tour for his new book, The Water Book. He amazed the audience with where our oceans came from (ice-covered rocks pelting the Earth during the Late Heavy Bombardment), the strange properties of ice (a bizarre solid that floats on its liquid), and the possibility of water and life on other planets.

Alok Jha
It was really the universal importance of water that struck me though. As Alok discussed, water is absolutely essential not just for life, but also to enable every aspect of our lives. Its unique properties make it a critical component of almost everything we make and do. In addition to household uses like showers and toilets, the UK uses a lot of water in manufacturing, agriculture and mining, amongst other things. One report suggested that the average person’s life requires 3400 litres of water a day in the UK, with a total global requirement of four trillion litres a year.

Water is scarce


Around 2.7 billion people are affected by water scarcity worldwide. Rivers are drying up or becoming too polluted to use, climate change is altering patterns of weather around the world and mismanagement of precious sources of fresh water has led to the prediction that by 2025, two thirds of the world’s population may face water shortages.

Image credit: Hasin Hayder.
Image used under: CC BY-NC-ND 2.0
You only have to read the news to see the warning signs.

Agriculture is a huge business in California, using 80% of the freshwater to raise livestock and grow two thirds of the USA’s fruits and nuts. California’s climate makes it ideal for growing a range of crops, assuming they can be irrigated. A recent NY Times article revealed that it takes 15.3 gallons of water to produce just 16 almonds, 1.4 gallons of water for two olives, and a whopping 42.5 gallons of water to grow three mandarin oranges. As Alok commented, the state is literally shipping its freshwater to the rest of the world as food. California is currently in its fourth year of drought, and strict laws banning water wasting have been put into place.

Last week, Californian farmers in the deltas of the Sacramento and San Joaquin rivers volunteered to use 25% less water, in a bid to avoid even harsher restrictions being imposed by the state government. These reductions came after uproar from Californian citizens, for whom water wastage was already illegal.

Water conflict


Image credit: Katie Tegtmeyer. Image used under:CC BY 2.0
In Brazil, São Paulo has been suffering through the worst drought in more than 80 years. The water supply has been restricted to just six hours per day, but millions of citizens have also had several days without running water. Tensions are beginning to rise, with protests, looting and outbreaks of violence in the city of Itu. The Guardian reported one resident as saying: “We spent four days without water, and we saw what it was like. We saw people behave like animals in our building, so imagine 20 million people”.

Imagine billions.

Crown Prince General Sheikh Mohammed bin Zayed al-Nahyan of Abu Dhabi has declared water is now more important for his people than oil. Egypt has vowed to stop Ethiopia’s construction of a dam on the Nile at “any cost”. Burma, Thailand, Laos, Cambodia and Vietnam look poised to suffer from China’s continued damming of the Mekong River. Water is predicted to be used as leverage, or as the target of terrorist attacks in the future. Paul Reig, Word Resources Institute, stated,
“Water is likely to cause the most conflict in areas where new demands for energy and food production will compete with the water required for basic domestic needs of a rapidly growing population”.
What can we do about this? It’s a problem almost as complex as the molecule itself, and I certainly don’t have the knowledge or expertise required to answer. Alok suggested that the value of water could be added into the final price of our products and services, to make people aware of how much they are consuming and to think twice before wasting it.

Whatever happens, we’re going to need massive global action on a range of issues. We need to use less water to grow our food and manufacture the items we use daily, we need to prevent shared resources being selfishly used, and we need better management systems in place to prevent further pollution or loss of freshwater. Only then will we be better prepared to face uncertainties of the future and ensure everyone has enough to drink.
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This blog is written by Cabot Institute member Sarah Jose, Biological Sciences, University of Bristol.

Sarah Jose

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