It's easy to declare safe drinking water a basic human right for all, but not so easy to ensure a safe water supply for the more than 1 billion people that still lack it.

Each day before dawn millions of women in Africa and Asia begin the chore that will consume many of their waking hours-fetching water for their families. They may walk for miles to collect water from a river, spring, or well. Often, the water they carry home is bringing their families not life and good health, but sickness and even death.

These women are among the 1.1 billion people around the globe who lack access to any improved water source-that is, a pipe, well, or protected spring. The developing world, especially Africa and Asia, remains in the midst of a water crisis that is exacting millions of casualties. According to the World Health Organization, the parasites, bacteria, and chemicals in unsafe water are killing 3.4 million people, mostly children, each year.

Many experts agree that each person requires a minimum of about 50 liters a day for drinking, cooking, bathing, and sanitation. Only about 5 to 10 liters of that water must be clean enough to drink.Yet many poor people get much less than 50 liters a day, of which virtually none is technically safe for drinking. Increasingly, a minimum amount of safe drinking water is recognized as part of a fundamental human right to food.

Although water scarcity is worsening worldwide, this is not necessarily the main reason so many people lack access to safe water. After all, compared with other water uses, the amount of water required for domestic use is small. According to Global Water Outlook to 2025: Averting an Impending Crisis, a new food policy report from IFPRI, in 1995 about 8 percent of the water used worldwide went for household needs, compared with about 86 percent for irrigation. On a national basis, access to safe drinking water depends less on a country's available water resources than on its level of wealth and its political commitment to safe water.World Bank figures show, for instance, that 70 percent of people in South Africa have access to an improved water source, compared with only 32 percent in its poorer neighbor Mozambique.

"Even though household water use is small," says Ruth Meinzen-Dick, an IFPRI senior research fellow, "the devil is in the details of ensuring that water is safe and getting it to the people who need it in an affordable manner. And people's quality of life depends on their access to water."

In 2000 the member states of the United Nations agreed to work toward cutting in half the number of people who do not have access to safe water and sanitation by 2015, as one of the Millennium Development Goals. At the September 2002 World Summit on Sustainable Development in Johannesburg, these countries reaffirmed this goal. Achieving even this limited goal, under which millions of people will still be without safe water, will require heavy commitments of money, time, and political will. Of course, failing to achieve the goal carries a heavy price as well.

IFPRI research has shown that diarrheal diseases can greatly exacerbate malnutrition because diarrhea prevents the body from using whatever nutrients are consumed. "The bottom line is that water is food," says Joachim von Braun, director general of IFPRI. "Therefore clean water is essential for food security and food safety."

Efforts to improve people's nutrition can be futile without attention to their water consumption. Patrick Webb, director of the Food Policy and Applied Nutrition Program at Tufts University, describes a project in The Gambia that introduced a new irrigation technology: "People who adopted the new technology grew more food and earned more income but made only relatively small improvements in their nutrition. This was because the wells from which they got their drinking water were still contaminated." If the project had also addressed the quality of their drinking water, the participants could have made greater improvements not only to their incomes but to their health and well-being.

Even where the quantity of water supplied has been improved, unexpected quality problems have arisen, at great human cost. In the 1980s and 1990s, several million tubewells were installed in Bangladesh, offering what was thought to be a safe water supply to millions of people who had previously been at risk from microorganisms in their water sources. Then in 1993, it was discovered that many of these tubewells were producing water contaminated with arsenic, a mineral found underground in many areas in Bangladesh that causes debilitating skin lesions and cancer when ingested. Now estimates say that between 35 million and 77 million people in Bangladesh are at risk of drinking this contaminated water. According to an article in 2000 in the Bulletin of the World Health Organization, "Bangladesh is grappling with the largest mass poisoning of a population in history."

As serious as the arsenic problem is, Jamie Bartram, of the World Health Organization, says excessive fluoride in water supplies may have even more severe consequences. "Excessive fluoride is a serious problem in China, India, and the Rift Valley of Africa. We know a little bit of fluoride is good because it protects your teeth, but if you consume too much, it produces gross skeletal deformities by the time people reach young adulthood. So just when people should be most productive, it takes them out of the productive work force quite effectively."

It is crucial to reduce the severity and duration of people's exposure to these chemicals, says Bartram, but removing them from dispersed water sources is not easy or straightforward. In Bangladesh, studies show that one pump may be contaminated with arsenic, while another just meters away may be safe. The government has painted many of the tubewells-red for contaminated and green for clean-but the wells must be regularly retested, as their status can change quickly.

It is increasingly standard practice for governments and NGOs to integrate water supply, sanitation, and hygiene projects.Turner says that improving hygiene "is the most difficult thing we do. You need to break oral-fecal transmission. If you can get people to wash their hands after using the toilet, you get major health benefits. The trick is to make it an automatic behavior."

Hygiene improvements are more effective when accompanied by sanitation facilities, which 2.4 billion people still lack. The problem is often most obvious in cities, where raw sewage runs through slum neighborhoods. In rural areas, where people may go out into the bush, the problem is less noticeable but no less serious. Human waste can seep into surface water and groundwater.

Rupert Talbot, an adviser with UNICEF in India, says, "In West Bengal, a popular marketing slogan is 'no marriage without a toilet.' The toilet is being promoted as an essential facility in a newlywed's house."

According to Meinzen-Dick, "One school of thought says that if people don't pay for water, they won't conserve it. But others say that even very low prices can be burdensome for very poor households."

The actual cost of supplying more clean water to a growing world population will certainly rise over the coming decades, says Mark Rosegrant, an IFPRI senior research fellow, because of the cost of developing new water sources and increasing competition for water between farmers, cities, and industries. "Water suppliers are going to have to raise prices even for their existing supplies," he says. "What makes the most sense is for water suppliers to raise prices for all users and then subsidize water for the poor."

Some areas are trying this approach, or a variation. The city of Chennai, India, secured its water supply by clamping down on unaccounted-for water-lost to leaks or unauthorized users-and then made a commitment to supply a minimum amount of water to all users. According to Paul Appasamy, director of the Madras School of Economics in Chennai, who has studied the system, "The quantity provided through the public system is extremely limited and has to be augmented in other ways. The poor are given water from public tankers that traverse the city. Better-off people get water from their own bore wells or from private vendors." The city is also promoting the harvesting of rainwater for people's household needs.

Lucy Akanboguure of Kandiga, Ghana, who benefited from a new water hand pump in her village, described some of the women's difficulties to WaterAid, which had helped supply the pump: "In my community women were expected to provide water every morning for their husbands. The lack of water often resulted in quarrels, wife beating, or even divorce. Communities suffered most from water shortages during the long dry season from November to March. Women quarreled, beat or injured one another, and even broke one another's containers and calabashes in the mad rush for water."

Partly because of women's inherent interest in safe water and sanitation, NGOs are making women important players in developing and maintaining these services. The Indian NGO Gramalaya, for example, has helped build communal latrines and water points in urban slums in India. These community toilets are managed by SHE teams-Sanitation and Hygiene Education teams-made up of members of women's self-help groups who collect fees from users and ensure that the toilets remain clean and in working order.

WaterAid's Turner explains, "Women are used as caretakers because they are at the center of their household. Men are more likely to have paid employment and may be away from home, while women do not have the same mobility and so remain caretakers for longer. As women are the main collectors of water, their motivation to maintain water points is stronger." This job can also serve as a valuable source of income for poor women.

"In itself," says Rosegrant, "privatization is neither a terrible thing nor a solution to all that ails us. Either a public or a private system can be managed efficiently, but you need to recover costs in order to maintain efficient service and expand services to meet the needs of rapidly growing urban populations, and you need oversight to ensure that the system is meeting the needs of the poor."

Buenos Aires, for example, privatized its water system in 1993. The move was highly controversial at first, says Rosegrant, but it later appeared to be generally successful. "The water company significantly expanded water service to the edges of the city and to poorer neighborhoods, and the pricing structure was such that the poor could afford the water."

In other cases, Rosegrant says, privatization has been less successful. "What's often missing," he explains, "is the idea that they have to supply social goods"- that is, they have a responsibility to provide clean water even to the poor.

It is the job of government to ensure that private water companies fulfill this responsibility to the poor, even while they seek profits. "The critical issue is the government's contract with the private water supplier-how it's written and whether it's enforced," says Meinzen-Dick.

Stephen Turner of WaterAid argues that the debate over privatization of water supply is probably moot in most of Sub-Saharan Africa. "For over 90 percent of the people, the public sector is going to be the water provider. There isn't a private sector company that will take this on, because it just isn't profitable enough," he says. "So the real question is: How do we strengthen the public sector?"

"The technology to be promoted, whether it is a community toilet or the newly innovated child-friendly toilet, should be based on the needs of the community," says S. Damodaran, executive director of Gramalaya. "It should be designed and located in consultation with the people who are really the ultimate beneficiaries.Users of the sanitation or water facilities need to have a sense of ownership."

Users sometimes make choices that surprise experts but make the most sense for local conditions.Ned Breslin, WaterAid's country representative for Mozambique, describes the isolated village of Maiaca, which had two hand pumps the villagers could not repair. They decided that protected wells with a bucket and a windlass would work better for them and worked with the district government and WaterAid to install them. "Since then they have had water and have repaired their water points when broken. In addition, the whole community now has latrines, and there have been massive improvements in the use of these latrines and in hygiene practices," Breslin reports.

One key to greatly expanding coverage to clean water and sanitation is to replicate successful solutions on a larger scale. This scaling up presents its own risks, however. A water system that works well in one community may be inappropriate for another. A sanitation system that succeeds on a small scale may present environmental risks when replicated thousands of times. Yet development professionals have little choice but to forge ahead, balancing the need for sustainable solutions with the need for greatly expanded water supplies and sanitation services.

"On a positive note," says UNICEF's Talbot, "the majority of countries we support are not starting from scratch. They have many years of experience. The risks to sustainable coverage and facility usage are well recognized by most."

In the end, the hope of many is that the Millennium Development Goals can help stimulate action toward solving a problem that has lasted far too long. IFPRI's von Braun acknowledges that the goals are admirable, though they will require major public and private investments and creative institutions. "In any culture the 'poisoned well' is a symbol of crime at its worst," he says. "In reality many of the poor in rural and urban areas are daily victims of the crime of inaction on the drinking water front. The needed investments will come about only through strong economic incentives combined with strong public advocacy."