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Health and Water Quality Standards

In order to ensure that tap water is safe to drink throughout the country and state, the Environmental Protection Agency and the Washington State Board of Health set limits on contaminants in water provided by public water systems. Seattle’s drinking water consistently meets those regulatory standards, and in most cases is far better than the standards. More information about testing results for Seattle’s water is provided here:

Drinking Water Quality Report
Water Quality Analyses

All drinking water, including bottled water, may reasonably be expected to contain at least trace amounts of some contaminants. The presence of trace contaminants does not mean that the water is unsafe. Limits on contaminants are set so we know which contaminants are a concern and at what level they are a concern. More information about contaminants and their potential health effects can be obtained by calling the Environmental Protection Agency’s Safe Drinking Water Hotline at 1(800) 426-4791.

For people with weakened immune systems

Some people may be more vulnerable to contaminants in drinking water than the general population. Immuno-compromised persons such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, and some elderly and infants can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers. The Environmental Protection Agency/Centers for Disease Control guidelines on appropriate means to lessen the risk of infection by Cryptosporidium and other microbial contaminants are available from the Safe Drinking Water Hotline at 1(800) 426-4791.