ABSTRACT
This chapter discusses water treatment techniques and disinfection practices to prevent transmission of disease. As water supply practice has evolved in the US in the past 100 years, efforts to provide safe drinking water and prevent outbreaks of waterborne disease have focused on protection of water quality and treatment to improve water quality. Some water systems rely on barriers to protect raw water quality, but those using major river systems must rely more heavily on treatment of the water than on protection of the source. Water filtration can remove a variety of particulate substances, including soil particles, algae, and microorganisms. The ability of slow sand filters to remove bacteria from drinking water was shown first by the decline in disease and death rates for waterborne diseases such as cholera and typhoid fever in areas served by water systems employing this treatment.
