Unsafe drinking water and inadequate sanitation cause more than 9% of all disease in the world, more than 6% of all deaths, and more than 20% of all deaths of children under the age of 5.

The diseases that impair the health and take the lives of millions of children include dysentery or diarrhea, malnutrition caused by diarrheal disease, cholera,intestinal parasitic infections, hepatitis A and hepatitis E, lymphatic filariasis, schistosomiasis, respiratory infections such as legionellosis and leptospirosis, and eye infections such as trachoma (causing blindness), conjunctivitis and otitis. (WHO 2008)

Roughly 3 million people in the world die each year of diarrheal and other water-borne diseases that could be prevented with adequate water, sanitation, and hygiene education. (WHO 2008)

Most people who die each year from inadequate water and sanitation are children under the age of five. (WHO 2008)

More people die each year from lack of water and sanitation than die of AIDS, hunger, and war. And both malnutrition and conflict are frequently caused by lack of water. (CW​S)

Community water and sanitation projects immediately reduce the incidence of water-borne disease and death by 50%. They are widely regarded as the most important preventative health intervention to reduce infant mortality.

Millennium Development Goals include Goal 7: environmental sustainability. Target 10 of Goal 7 calls for halving the percentage of the population in each nation that lacks clean drinking water and sanitation between 2000 and 2015. About 1/2 of the world's developing nations are on track to meet this goal, but about half are not.

Most people without clean water and sanitation are poor people living in the poorest and least developed countries in the world. These people have little hope that their governments can provide them with water and sanitation.