Global water scarcity and how to deal with it

By Dr Rosie Bosworth

APN / NZ HERALD·

31 Jul, 2015 02:23 AM8 mins to read

Global water use is four times greater than population increase rates. Photo / Getty Images

Never mind peak oil. Let’s talk about solving the next big global crisis. Peak water.

For Kiwis concerns about water scarcity often fall on deaf ears. For the most part, and in most areas, we have rain, and plenty of it. But for the rest of the world access to fresh water is a precious, rare and rapidly diminishing luxury. As the population continues to rise and severe drought grips nations around the world, the planet's water quality and aquifers are being rapidly depleted.

The World Bank says two billion people are running out of water. Moreover, a recent UN report revealed that if we continue along this trajectory, by 2030 the world will only have 60% of the water it needs. The regions hardest hit? China, India, the Middle East and the United States.

An array of solutions promoting a water-secure future are emerging across governments, businesses and individuals worldwide.

In water-parched California, brown is being marketed as "the new green" in a bid to change residents' behaviour to ease the burden of a four-year drought. As strict water restrictions are enforced, residents and business are incentivised to forget about looking clean and green and replace water-hungry gardens with drought-friendly plants. Fake grass is cropping up everywhere.

In Hong Kong, residents are using seawater to flush their toilets as authorities try to preserve scarce fresh supplies and, in drought stricken Australia, there is a rotating week policy for residential irrigation and car washing.

Legislation is just one means to combat water scarcity. Business is also joining the race to simultaneously save a drop and make a buck as investors are showing increasing interest in ventures that preserve or enhance water.

Jordan's Amman, California's San Francisco and Cáceres, Spain are among the many cities worldwide now deploying municipal-level smart water systems. GreentechMedia suggests regions that adopt this technology have the potential to reduce water demands by 25%, necessary for achieving the proliferation of municipal water cuts mandated globally.
In horticulture, precision technologies, water-efficient crops and smart irrigation systems equipped with solar-powered stations and wireless soil sensors now enable farmers to grow more crop per drop and alter water inefficiencies as they happen. Israeli manufacturer Itron recently began deploying ultrasonic water metering technology designed for Middle Eastern conditions. The technology has applications for other arid regions including Australia and France's African territories.

World leaders in drip irrigation, Netafim, based in Tel Aviv, now exports its technology as the focus towards water-saving technologies becomes an agricultural phenomenon. US farmers have already reduced water use by 20% by adopting such technology.

While regulations and technology promoting smarter water use are critical, these alone may be futile in the absence of mechanisms that put a price of the real cost of water. According to Ian McDonald, senior lecturer of food and resource economics at Lincoln University's Faculty of Agribusiness and Commerce, societies have long used prices and markets to ration scarce resources. Water should be no exception. "With water priced according to its value to society, people will make decisions that balance the financial benefits of water conservation - in terms of having to pay a smaller water bill - with the costs of conservation technologies." With a more accurate price on water investing in research and development of better technologies also becomes economical as water becomes a valuable commodity.

Voluntary measures are helping. In May this year California State officials accepted an offer from farmers in the Sacramento-San Joaquin River Delta to relinquish a quarter of their water rights this season, leave part of their land unplanted and adopt alternative measures to curb water use. In return, the state will hold fire on additional restrictions later into the growing season.

"The reason why Californian farmers volunteered to give up 20% of their water rights is not really because they are nice or environmentally sensitive, but because they are charged a high price for water," says McDonald. "Essentially with the poor land productivity sections of their operations, farmers are earning insufficient profit from their crops to pay for the water hence deciding to not farm it. In New Zealand - where we don't pay for water - more and more land is being converted to dairy even though it is not very productive. This is despite being warned about droughts increasingly occurring."

Domestically, the shower, washing machine and humble lavatory are further examples of daily water users being reinvented. RTI Research (US) has developed a waterless lavatory that generates electricity and is now testing prototypes in Gujarat, India with investment from the Gates Foundation. British company, Xeros, designs washing machines which use 70 per cent less water and 50 per cent less energy and detergent than conventional versions, using polymer beads to remove stains. A hit across US laundromats and hotel groups, orders are coming in worldwide. And small-scale energy efficient desalination systems mimicking the biological processes of mangrove plants and hybrid fish to extract salt content as well as nano water purification technology are being explored across the UK, Singapore and India as water pollution reaches an all-time high.

Big business is also shaking up established ways by spending more to cut water use. Nestlé recently unveiled a milk plant upgrade in Mexico that requires no external water sources and recycles waste fluid extracted from milk when powdered.

What is clear in the race to save water is that business, governments and individuals all have a role to play to combat water scarcity. But according to MacDonald, a price on water will be most effective. "In order to make decisions about how much water gets used, for what (agriculture, recreation, urban, etc), when and by whom - markets will always work the best".

Global challenge - fresh water

Fixed supply - increasing demand: the amount of freshwater available on the planet remains more or less constant. Water is continually recycled through the atmosphere. However as global population grows, competition for a clean supply of water for drinking, cooking, bathing, and sustaining life has intensified and become more limited.

Water use is four times greater than population growth rates: while the world's population growth in the last century has doubled the rate of global water consumption per capita in the last 40 years has quadrupled.

Global supply of fresh water is limited:
2.5% Amount of the world's total water supply comprising freshwater .
1% Quantity of fresh water globally easily accessible for human use
29% of fresh water is located underground.
90% of the world's readily available freshwater sourced via ground water

Aquifers (ground water basins):
1.5 billion: people dependant on ground water for drinking supply
1/3 of the world's 37 largest aquifers now classified as 'stressed' - more water is removed than can be replenished (Journal of Water Resources)
Eight of world's largest and aquifers that have virtually no natural replenishment to offset human consumption

Agriculture is the biggest user of fresh water at 70%. Agriculture is also a key contributor to water pollution from excess nutrients, pesticides and other pollutants.

80% of agricultural irrigation needs is provided by rain-fed sources
1 billion extra mouths to feed by 2025, requiring an extra 1 trillion cubic meters of water for agriculture alone (Seametrics)

Industry is responsible for 22% of fresh water use. Largest share of fresh water stored in reservoirs and dams for electricity energy production and irrigation is used for industry
Domestic use 8%: the average amount of water consumed daily by people in developed countries is ten times higher than those in developing countries.

The world's top irrigators: pumping groundwater faster than it is being replenished in crucial crop-producing areas; China, India, Pakistan, US

Disease: according to water.org more than 750 million people lack access to clean water. Approximately 1 in 9 people or two and a half times the population of the United States of America.

More than 840,000 people die each year from water-related disease. Every minute a child dies from a water-related disease.

Water Investment: according to the OECD for every $1 invested in water and sanitation there is a $4 economic return. Gaining universal access to adequate water and sanitation would result in an estimated $18.5 billion in economic benefits per year from deaths avoided. Only 6% of international aid went towards investments in water and sanitation in 2011.

This global challenge series has been made possible with support from Lincoln University. Lincoln University is among our more progressive on these issues, with three overarching organisational goals; to feed the world; protect the future; and live well. It's with these three goals in mind that every Lincoln course is now designed, and first and second-year students are required to undertake courses in understanding global challenges and the opportunities that lie in solving them.