Drinking Water and Your Health

Metropolitan Water District of Southern California

As water travels over the surface of land or through the ground, it can pick up matter left behind by animals or people, and it dissolves minerals and, sometimes, radioactive material.

Water is treated at one of five Metropolitan-owned and -operated treatment plants in the Southland. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants.The presence of contaminants does not necessarily indicate that the water poses a health risk. You can learn more about contaminants and potential health effects by calling the U.S. Environmental Protection Agency's Safe Drinking Water Hotline at (800) 426-4791 or visiting their Web site .

In order to ensure that tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. Food and Drug Administration regulations establish limits for contaminants in bottled water. Both sets of requirements protect public health.

Contaminants that may be present in water before some treatment include:

Pesticides and herbicides
that may come from a variety of sources such as agriculture, urban storm-water runoff, and residential uses.

Microbial contaminants,
such as viruses, bacteria and protozoa that may come from sewage treatment plants, septic systems, agricultural livestock operations and wildlife.

Radioactive contaminants
which can be naturally occurring or be the result of oil and gas production, and mining activities




	Organic chemical contaminants including synthetic and volatile organic chemicals that are by-products of industrial processes and petroleum production, and can also come from gas stations, motorized watercraft, urban storm-water runoff and septic systems.		Inorganic contaminants such as salts and metals, that can be naturally occurring or come from urban storm-water runoff, industrial or domestic wastewater discharges, oil and gas production, mining or farming.