In Nairobi, Kenya, enough water is lost through leakage or theft to supply the nation’s second-largest city.
In China, government figures show 300 cities suffer serious water shortages.
Around the world, ensuring adequate supplies of fresh water is becoming a major problem because of growing population, urbanization and environmental degradation.
The United Nations hopes to draw attention to the problem during the U.N. Conference on Human Settlements set for June 3-14 in Istanbul, Turkey.
“I suspect that in the next 50 years, we will see a shift from oil to water as the cause of great conflicts between nations and peoples,” said Wally N’Dow, secretary-general of the Istanbul conference.
“There is a tremendous economic and human cost involved due to inadequate supplies of water,” he said.
The effects of inadequate water supplies are felt the strongest in the developing world, N’Dow said.
Throughout the developing world, an estimated 20 percent of urban families buy water from vendors because they have no access to municipal systems.
In Khartoum, Sudan, for example, families with access to the city water system pay about $2.60 a month for service. But Khartoum families who buy from vendors, who deliver sacks of water by donkey, pay an average of $16 a month.
That can amount to about 35 percent of a poor Khartoum family’s monthly income, according to U.N. studies.
Poor water supplies also take an enormous toll on public health.
The United Nations estimates that only 5 percent of the waste generated in cities worldwide is treated chemically before it is dumped into rivers or onto the ground.
Pollutants then slowly seep their way back into streams and ground water and end up back in the drinking water.
A 1991 cholera outbreak in Peru, brought about by substandard water and sewer systems, cost the country about $1.5 billion in lost tourism and fishing revenues, according to the U.N. Development Program.
“In Europe, 40 or 50 years after the installation of a good water system, life expectancy, in the case of France, jumped by an average of 30 years,” N’Dow said. “Developing countries must go along the same path.”
But developed countries are not immune from the problems. N’Dow cited declining water supplies in the western United States, where booming populations in Southern California, Arizona and parts of Texas have strained resources.
U.N. officials say the answer lies in upgrading and expanding water distribution and purification systems. During the Istanbul conference, N’Dow said, participants will discuss new technology and exchange ideas on how to improve and finance water systems.