Earth Science
Human Impacts on the Earth Environment
Safety of Water
Study Tip
Nearly one-fifth of the world population has no access to clean water.
Water Treatment
Unsafe water contains many
pathogens,
which causes a variety of diseases.
Natural sources of water are treated with disinfectants such as chlorine, to kill bacteria and other microscopic pathogens.
In most communities in the United States, water undergoes a lengthy process before ending up in drinking fountains.
Study Tip
Nearly one-fifth of the world population has no access to clean water.
Water Treatment Process
The water treatment process involves the following five steps:
Coagulation
Sedimentation
Filtration
Disinfection
Storage
Effects of Water Pollution
Drinking unsafe water causes approximately 88% of all diseases.
Throughout the world, more than 14,000 people die every day from waterborne diseases such as cholera and Guinea Worm disease.
Concept Check
What do waterborne diseases from unsafe drinking water lead to?
How is water treated in many communities across the United States?