As hundreds of thousands of terrified Rwandans poured across the border, they crashed into a cruel illusion. Sparkling in the tropical African sun, the vast expanse of Lake Kivu stretched away to the horizon, offering the bedraggled army of displaced people the hope of immediate and unlimited supplies of life-saving water.

But as the exodus continued relentlessly, the Rwandans were pushed further and further away from the lake, finally settling into the nooks and crannies atop a dry plain of black and grey volcanic rock dozens of miles away.

In a matter of days in the summer of 1994, more than one million Rwandans trying to escape the ongoing genocide in their country, tumbled into neighbouring Zaire (today the Democratic Republic of the Congo). In the following weeks, despite a multi-billion dollar international aid effort, as many as 60,000 died from a vicious cycle of water shortages, disease and, inevitably, cholera.

As the world population has more than doubled in the past 60 years, an increasing number of people are facing water shortages, threats to their economic and environmental well-being, their health and like the Rwandans, their very lives. Groundwater, the unseen source of life for two billion people, is diminishing at an alarming rate almost everywhere.

Some 450 million people in 29 countries live with chronic water shortages. One person in six has no access to safe drinking water and more than two billion people have no adequate sanitation. Waterborne diseases kill a child every eight seconds and are responsible for 80 percent of all illnesses and death in the developing world.

Refugees and other displaced groups are among the most vulnerable of the vulnerable.

Uprooted peoples often escape from the world's poorest nations, only to find sanctuary in equally destitute countries. Refugee camps are sometimes located in thinly populated parts of a country where there is little infrastructure and, most importantly, little water.

HOT AND DRY

The Horn of Africa, home in the last few decades to hundreds of thousands of refugees from Sudan, Eritrea, Ethiopia and Somalia, is one of the hottest and driest spots on earth. Sudan has an estimated four million people on the move, but much of the country is desert or scrub. Even when water is tantalizingly close, as in the case of the fleeing Rwandans, it may still be difficult to access because of political or military problems.

In such often inaccessible regions, in the middle of a war, water can be prohibitively expensive and difficult to deliver even when its need is recognized as paramount. An adult can live for several weeks without food, for instance, but in extreme conditions, two or three days without water turns into a sentence of death.

In Zaire, the United States military eventually used heavyweight Galaxy transport aircraft to move water pumping stations halfway across the world to tap into Lake Kivu. It then cost $10,000 a day to get the minimum acceptable amount of water – around 7 litres per day per person – to 200,000 people in one camp only a few miles away.

In parts of the Horn in the 1990s, some refugees were forced to survive on less than three litres per day.

Access to water is a basic human right, and together with partners such as water specialist Oxfam, UNHCR is already involved in a variety of water-related projects around the world. They include not only trucking supplies to isolated camps, drilling wells, maintaining generators and water pumps, but also building dams and rehabilitating lakes and rivers to help protect the environment and, where possible, encouraging small-scale fishing and agricultural programmes to help make refugees self-sufficient.

To mark the International Year of Freshwater in 2003, the agency launched a global survey to identify any major gaps in its programmes to provide safe water to the more than 20 million people it cares for worldwide.

Improvements probably will include a more systematic collection and use of data, improved cooperation with other agencies and better use of groundwater and rainwater catchments.

Funds permitting, of course. As budgets became tighter, the refugee agency has been forced to slash the amount of money available for research and development projects, training and on-the-ground programmes.

"We need to learn how to value water," U.N. Secretary- General Kofi Annan said recently, referring to the continuing wasteful use of water in many parts of the world.

That is one lesson most refugees have already taken to heart.