Water pollution is a major global problem that causes over 14,000 daily deaths. Many developing nations struggle with issues of access to clean water and sanitation. In India, 700 million lack access to toilets and 1,000 children die daily from diarrheal sickness, while in China, 90% of cities suffer water pollution and 500 million lack access to safe drinking water. Developed nations also continue to face pollution challenges. Water pollution comes from a variety of sources including sewage, chemicals from industry and agriculture, microorganisms, excess nutrients, oxygen depletion, and suspended solids. Proper treatment of sewage and wastewater is needed to protect water quality and public health.