Water is essential to human health. The human body can last weeks without food, but only days without water. Water is essential to our survival. Regular handwashing, is for example one of the best ways to remove germs, avoid getting sick, and prevent the spread of germs to others. Up to one trillion germs can live in one gram of poop.
As for the human body, in average it is made of 50-65% water. Babies have the highest percentage of water; newborns are 78% water. Every day, every person needs access to water for drinking, cooking and personal hygiene. Water is essential for sanitation facilities that do not compromise health or dignity. The World Health Organization recommends 7.5 liters per capita per day will meet the requirements of most people under most conditions. A higher quantity of about 20 liters per capita per day will take care of basic hygiene needs and basic food hygiene.
Despite impressive gains made over the last decade, 748 million people do not have access to an improved source of drinking water and 2.5 billion do not use an improved sanitation facility. Investments in water and sanitation services result in substantial economic gains. The return on investment of attaining universal access to improved sanitation has been estimated at 5.5 to 1, whereas for universal access of improved drinking-water sources the ration is estimated to be 2 to 1.To cover every person worldwide with safe water and sanitation is estimated to cost US$ 107 billion a year over a five-year period.
– See more at: http://www.unwater.org/worldwaterday/learn/en/?section=c325497#sthash.iflvocv9.dpuf