Water shortages threaten human food supply

Posted: 18 February 2008

Author: Henrylito Tacio

If more and more countries, in Asia and elsewhere, find themselves very short of food in the near future, blame water shortage for the situation, says Henrylito Tacio, in this report from the Philippines.

Water for agriculture is critical for food security," says Dr. Mark W. Rosegrant, a senior research fellow at the Washington-based

Women at a waterpump, Tidi, Rajasthan,
Women at a waterpump, Tidi, Rajasthan,
Women at a waterpump, Tidi, Rajasthan, India. Photo © Kai Friese/People & the Planet.
International Food Policy Research Institute (IFPRI). "The link between water and food is strong," says Lester Brown, president of Earth Policy Institute, also based in Washington DC. "We drink, in one form or another, nearly 4 litres of water per day. But the food we consume each day requires at least 2,000 litres to produce, 500 times as much."

In the Philippines, agriculture has the highest demand of all water use with 85 per cent while the other sectors - industry and domestic - have a combined demand of only 15 per cent. "With the demand for water growing in all three categories, competition among sectors is intensifying, with agriculture almost always losing," says Lester Brown.

Today, an estimated 40 per cent of agricultural products and 60 per cent of the world's grain are grown on irrigated land. "Agriculture is by far the biggest consumer of water worldwide," says the Laguna-based International Rice Research Institute (IRRI).

Water for fish

Within the agricultural sector, crop production receives the greatest attention, but fish and livestock also require water. "Animals (including fish) consume a relatively small volume of water in comparison to crop consumption and can produce a very high value of output," says Dr. Ruth Meinzen-Dick, a development sociologist who has done extensive research on water management. "As worldwide demand for animal products increases, the importance of supplying water for aquaculture and livestock is also likely to increase."

Water covers over 70 per cent of the earth's surface and is a major force in controlling the climate by storing vast quantities of heat. About 97.5 per cent of all water is found in the ocean and only the remaining 2.5 per cent is considered fresh water. Unfortunately, 99.7 per cent of that fresh water is unavailable, trapped in glaciers, ice sheets, and mountainous areas.

Water is drawn in two fundamental ways: from wells, tapping underground sources of water called aquifers; or from surface flows - that is, from lakes, rivers, and man-made reservoirs. Groundwater is recharged by rain and seepage from rivers.

"Water is the most precious asset on Earth," says Dr. Sandra Postel, director of the Massachusetts-based Global Water Policy Project. "It is the basis of life." Ideally, a person should have at least 50 litres of water each day to meet basic needs - for drinking, food preparation, cooking and cleaning up, washing and personal hygiene, laundry and house cleaning.

Population link

In Asia, around 1,444 cubic kilometres of freshwater is withdrawn annually for human use. "That is equivalent to about 500 cubic metres per person per year," explains Thierry Facon, senior water management officer of the regional office of Food and Agriculture Organisation (FAO) in Bangkok, Thailand.

Among Southeast Asian countries, the Philippines ranks second from the lowest in terms of per capita water availability per year with only 1,907 cubic metres, according to a recent report released by the World Bank. The country is now home to more than 80 million people.

Woman carrying water, Ethiopia. Photo: WHO/P. Virot
Woman carrying water, Ethiopia. Photo: WHO/P. Virot
Woman carrying water in a jar near Alem Kitmama North East of Addis-Ababa, Ethiopia. Credit: © WHO/P. Virot
"Water resources and population are closely connected," argues Don Hinrichsen, contributing editor of this website and an environmental journalist who has done studies on water crisis for Johns Hopkins University and Woodrow Wilson International Center for Scholars.

"The rapid urbanization of the Philippines, with more than 2 million being added to the urban population annually, is having a major impact on water resources," notes the Asian Development Bank (ADB) in its recently-released, Asian Water Development Outlook 2007. In Metro Manila, for instance, residents often complain of lack of water during the summer months. In some parts of the metropolis, the water supply situation reaches a vulnerable state that the little amount water some residents get is not enough even for emergency purposes like cooking and drinking.

Reaching the limits

"Water use has been growing at more than twice the rate of population increase in the last century and an increasing number of countries are reaching the limit at which reliable water services can be delivered," Facon notes.

Several factors contribute to water shortage, including variability in climate, demographic patterns, and unsustainable water-use patterns. In some urban centres of the Philippines where water is available, 50 per cent never reaches the designated consumers due to leakage, theft and poor management. These identified problems are compounded by the degradation of water resource base.

For instance, many of the country's largest cities are located in watersheds (also called catchment areas or drainage basin) where all available water is being used. "Land use and vegetative cover in the watershed are very important because they affect water flow and water quality," explains Patrick Durst, senior forestry officer of FAO's regional office in Bangkok, Thailand.

Forests can help

One indicator of a good watershed is a healthy forest. "This is because forests can help to relegate the flow of water," says Durst. A recent report released by the Department of Environment and Natural Resources (DENR) said that 90 percent of the 99 watershed areas in the country are "hydrologically critical" due to their degraded physical condition as a result of loss of forest cover.

"One of the most formidable environmental challenges the Philippines faces today is its diminishing forest cover," the World Bank report claims. "Of the country's total forestland area of 15.88 million hectares, only 5.4 million hectares are covered with forests and fewer than a million hectares of these are left with old growth forests."

River pollution also contributes to the country's current water woes. The ADB report said that 16 rivers are now considered "biologically dead" during dry months. Some 48 per cent of water pollution come from domestic waste, 37 per cent from agricultural waste, and 15 per cent from industrial waste.

Human future

In the rural areas, the major source of water pollution comes from farms. These are in the forms of organic wastes (such as decayed plants, livestock manure, and dead animals), soil loss (suspended soils and erosion), and pesticides and fertilizer residues.

Elephants at a water hole in  Kenya
Elephants at a water hole in Kenya.
Elephants at a water hole in Kenya. As humans expropriate more and more water, there is less to support wildlife and ecosytems. Photo © Don Hinrichsen
"When water is polluted, fish and other aquatic resources can perish, which leads to a decline in fisheries production," the World Bank report states. The Philippine economy loses an average of P17 billion annually due to the degradation of fisheries environment.

Meanwhile, Dr. Postel believes water problems will be alongside climate change as a threat to the human future, and global warming will worsen water problems. "Although the two are related, water has no substitutes," she explains. "We can transition away from coal and oil to solar, wind and other renewable energy sources. But there is no transitioning away from water to something else."

Henrylito D. Tacio is an award-winning journalist based in Davao, in the southern Philippines, and People & the Planet Contributing Editor for South East Asia