Boil Water Orders and Boil Water Advisories

Water Protection Program fact sheet
Division of Environmental Quality Director: Leanne Tippett Mosby

What is a boil water order?
A boil water order is issued by the Missouri Department of Natural Resources to public water systems when a threat to the public health exists, or is likely to exist, that boiling the water will remedy. The public water system is then required to notify consumers as soon as possible, and by the most effective methods, that need to boil their drinking water.

What is a boil water advisory?
A public water system may issue a boil water advisory when there is concern that a problem with drinking water may exist, but it has not yet been confirmed. These are most commonly issued for major water main breaks or other low-pressure events where the possibility of contamination intrusion exists.  They may also be issued while waiting for results of confirmation samples collected for bacteriological analysis, which can take up to two days plus the time required to transport samples to the laboratory.

What precautions should I take if under a boil water order or advisory?
The following steps need to be taken:

  1. Boil water vigorously for three minutes prior to use. Use only water that has been boiled for drinking, diluting fruit juices, all other food preparation and brushing teeth.

  2. Dispose of ice cubes and do not use ice from a household automatic ice maker. Remake ice cubes with water that has been boiled.

  3. Disinfect dishes and other food contact surfaces by immersion for at least one minute in clean tap water that contains one teaspoon of unscented household bleach per gallon of water.

Note: Let water cool sufficiently before drinking (approximately 110 degrees F).

Do I need to boil bath water?
Water used for bathing does not generally need to be boiled. Supervision of children is necessary while bathing or using backyard pools so water is not ingested. Persons with cuts or severe rashes may wish to consult their physicians.

What are the causes of boil water orders?
The presence of fecal coliform or E. coli bacteria is a common cause for issuing a boil water order. Other instances include low water pressure and inadequate levels of chlorine at systems that require chlorination. High turbidity levels, cross connections, inadequate treatment techniques and the presence of other microbial pathogens such as Giardia or Cryptosporidium are potential causes for boil water orders that occur less frequently.

What are the symptoms of water-borne illness?
Disease symptoms may include diarrhea, cramps, nausea and possible jaundice and associated headaches and fatigue. These symptoms, however, are not just associated with disease-causing organisms in drinking water; they also may be caused by a number of factors other than your drinking water.

Are some groups of people more seriously affected?
Persons with reduced immune function, infants under six months in age, and the elderly are more seriously impacted by water-borne disease. Immune function may be reduced due to chemotherapy for treatment, organ transplants or diseases such as HIV/AIDS. Persons in these groups need to contact their personal physicians for additional information.

Should I buy bottled water just to be on the safe side?
Buying bottled water may be a feasible alternative to boiling drinking water when under a boil water order. Bottled water operations are routinely inspected, and samples are analyzed by state health agencies. This offers a safe source of water for drinking, cooking and brushing teeth.

Where can I get more information?
To learn more about your drinking water, contact the department at 800-361-4827 or the EPA’s Safe Drinking Water hotline at 800-426-4791 if you are served by a public water system. If you get your drinking water from a private well, contact the Missouri Department of Health and Senior Services at 800-392-0272.