Access to safe drinking water is increasingly under threat across Asia and the Pacific as growing populations and industrialization undermine water quality.
United Nations water resource experts say with a population of four billion people, the Asia-Pacific region faces the risk of conflicts over water as communities struggle to meet their needs.
In a new report, U.N. says water availability in Asia and the Pacific is the second lowest in the world due to the region's high population.
Agriculture consumes about 80 percent of the region's water. But there is increasing use by industry. China and Vietnam had more than tripled industrial water use since 1992.
Lee-Huu Ti is chief of the water security section with the United Nation's regional economic and social commission in Bangkok. He says the problem is not just the amount of water, but the quality.
"Water quality the deterioration water quality is a serious issue in Asia," he said. "More and more water is polluted because of development most of the city urban areas the water has become much more dirty than before. Much more polluted than before - this is a general trend."
The issue is getting new attention this year because of a drought in Southeast Asia and southern China. Water levels in major rivers and lakes have fallen to the lowest point in more than 50 years in some areas.
While governments are stepping up efforts to meet Millennium Development Goals on water access by 2015, more than 600,000 people in the region still do not have safe drinking water.
The development goals include halving the proportion of people without sustainable access to safe drinking water and basic sanitation.
Ermina Sokou, an environmental affairs officer in the U.N. water resources section, says inadequate sanitation undermines efforts to improve drinking water access.
"Access to sanitation, that is a big issue and it's bringing the whole household water security level down. It affects human health, it affects environmental health and it also affects water quality, because a lot of pollutants that came from households and human settlements in the water are causing a lot of diarrhea diseases," said Sokou.
The report warns water supplies could deteriorate in many countries, particularly some of the region's poorest. The Maldives, India, Pakistan, and Uzbekistan, Afghanistan and the Philippines all face shortages because of declining supplies, poor quality or rising populations.
Lee Huu says there conflicts over water access may increase within countries, as different communities compete for dwindling supplies.
"The conflict or the dispute between stakeholders within a country is increasing drastically. [But] the dispute or conflict between each individual or stakeholder in a country can be managed by the law of the countries," said Lee.
He says that a Chinese study showed that in 1990, there were more than 10,000 disputes over water a year. By 2005 the number was 12,000. But China had moved to reduce local conflicts by passing new laws to help settle disputes in the communities.