Demand for water has never been as great as it is today, and it will only increase due to population growth and mobility, rising living standards, changes in food consumption, and increased energy production, especially biofuels. Access to basic water-related services (safe drinking water, sanitation and food production) remains inadequate in much of the developing world.
The “business as usual” scenario means an estimated 5 billion people (67% of the world population) may still be without improved sanitation in 2030. While current trends suggest that over 90% of the world population will have access to improved sources of drinking water by then, progress in basic sanitation remains inadequate.
The link between poverty and water resources is obvious: the number of people living on less than US $1.25 a day coincides approximately with the number of those without access to safe drinking water. This situation has a major impact on health. Almost 80% of diseases in developing countries are associated with water, causing some three million early deaths. For example, 5,000 children die every day from diarrhea, or one every 17 seconds. In all, about one tenth of all illnesses worldwide could be avoided by improving water supply, sanitation, hygiene and management of water resources.
Pressure Due to Increased Demand
While part of the population still lacks adequate access to water, demand has never been greater. Freshwater withdrawals have tripled over the last 50 years, while the area under irrigation doubled during the same period. This phenomenon is particularly linked to population growth. The world’s population, currently estimated at 6.7 billion, is growing by about 80 million people each year. This means demand for freshwater is increasing by 64 billion cubic meters (84 billon cubic yards) a year. Yet 90% of the population growth of three billion expected by 2050 will be in developing countries, many in regions which already are water scarce.
Population growth implies increased demand for agricultural products, and so increased demand for water is directly impacted. Agriculture is by far the greatest consumer of water, accounting for 70% of all water consumption (compared to 20% for industry and 10% for domestic use). Unless agricultural water use is optimized, water demand for agriculture worldwide would increase by 70% to 90% by 2050, even though a number of countries are already reaching the limits of their water resources.
Effect of Lifestyles and Eating Habits
At the same time, there have been changes in lifestyles and eating habits in recent years, in particular an increase in the share of meat and dairy products consumed in emerging countries. The production of a kilo of wheat requires 800 to 4,000 litres of water, while a kilo of beef, takes 2,000 to 16,000 litres. It is estimated that the Chinese consumer who ate 20 kilos of meat in 1985 will eat over 50 kilos in 2009. This will mean an additional 390 km3 of water for China’s production. By comparison, in 2002, the consumption of meat per inhabitant was 76 kilos in Sweden and 125 kilos in the USA.
Water Demand from Production of Biofuels
The production of biofuels has also increased sharply in recent years, with significant impact on water demand. The production of ethanol, 77 billion liters in 2008, tripled between 2000 and 2007 and should reach 127 billion litres by 2017. Brazil and the USA, which satisfy 77% of world demand, are the main producers. In 2007, 23% of maize production in the USA and 54% of Brazil’s sugar cane crop were used for ethanol production. In 2008, 47% of vegetable oils produced in the European Union were used for biodiesel fuel.
But, despite the increased use of crops for biofuels, the proportion of total production is still small. In 2008, the ethanol share of the transport fuel market was estimated at 4.5% for the United States, 40% for Brazil and 2.2% for the European Union. The report says that, despite their potential to help reduce dependence on fossil energy, biofuels, with current technology, are likely to place a disproportionate amount of pressure on biodiversity and the environment. The major problem is the need for large quantities of water and fertilizers to grow the crops. Between 1,000 and 4,000 litres of water are needed to produce a single liter of biofuel.
Accelerating Energy Demand
Meanwhile, energy demand is accelerating, with corresponding implications for water demand. Global energy demands are expected to grow by as much as 55% through 2030. China and India alone would account for about 45% of this increase. Electricity generation from hydropower is projected to increase at an average annual rate of 1.7% from 2004 to 2030 — an overall increase of 60%.
Possible Solution from A Potential Foe
Criticized for their heavy footprint on the environment and their tendency to displace large numbers of people, dams nevertheless seem, for many, to offer a solution, given diminishing fossil fuel supplies, the need to shift to cleaner energy sources and the potential use of added storage in adapting to the increased hydrologic variability and uncertainty due to climate change. The energy aspect is particularly true for developing countries, where the potential for hydropower is considerable.
Investing in Water
The future wealth of developing countries will partly depend on their investment in the water sector. Investing in water can pay off in several ways. Each dollar invested in improved access to safe water and sanitation will produce an estimated return of US$3 to US$34. On the other hand, where investment is weak, gross domestic product (GDP) could be constrained by as much as 10%. On the African continent, the overall economic loss due to lack of access to safe water and basic sanitation is estimated to be about US$28.4 billion a year, or around 5% of GDP.
Investing in sanitation infrastructure also has benefits for the environment. Over 80% of sewage in developing countries is today discharged without being treated thereby polluting rivers, lakes and coastal areas. It is estimated that the total cost in industrial countries of replacing aging water supply and sanitation infrastructure may be as high as US$200 billion per year.
Improved Water Management
Confronted with growing scarcity, some countries have already started to integrate their water resource management strategies with their development plans. In Zambia the new integrated water resources management policy is intent on integrating water management throughout all sectors. As a result, many donors have incorporated water-related investment in their assistance packages to Zambia.
Turkey’s Southeastern Anatolia Project (GAP) is a multisectoral, socioeconomic development project designed to raise incomes in this less-developed region. The overall cost of the GAP is projected at $32 billion, of which $17 billion has been invested. Per capita farm incomes have tripled since irrigation was expanded. Rural electrification and accessibility reached 90%, literacy rates rose, infant mortality rates fell, business start-ups increased, and a more equitable land tenure system evolved in irrigated areas. Urban settlements served with water supply quadrupled. The region is no longer the country’s least developed economy.
Australia has also changed its policies, with a range of new measures. Restrictions have been introduced – on watering gardens, washing cars, filling swimming pools, etc – in the country’s major cities. In Sydney, a dual water supply was introduced in 2008 – one for drinking water, another for other uses, which draws on recycled water.
Both urban distribution networks and irrigation schemes are highly inefficient if judged by the amount of water lost through leakage. In the Mediterranean region, it is estimated that 25% of water is lost in urban areas and 20% in irrigation canals. At least part of this loss could be avoided. Cities such as Tunis (Tunisia) and Rabat (Morocco) have succeeded in cutting their losses to 10%. And, in Bangkok (Thailand) and Manila (Philippines), leak-detection programs are being implemented.
Wastewater treatment can also increase the availability of useable water. Some countries are already recycling treated waste water for agricultural use. But urban waste water use in agriculture remains limited, except in a few countries with very meager water resources – 40% of uses in the Gaza Strip (Palestinian Territories), 15% in Israel and 16% in Egypt.
Desalination of sea water is another process used in arid regions. It is used to obtain drinking water and for industrial use in countries that have reached the limits of their renewable water resources (e.g. Saudi Arabia, Israel, Cyprus).