Boil Water Emergencies

Sometimes a situation occurs where the safeness (due to biological or chemical contamination) or the availability of water is a concern for the proper operation of a food service facility. When the water supply may have been biologically contaminated a Boil Water Advisory will be issued. If it is confirmed that the water supply has been biologically contaminated, a Drinking Water Warning (sometimes called a Boil Water Notice or a Tier 1 Notice) will be issued.

If a boil water advisory is issued for your area, it means that the water supply in your area may be contaminated, either by a sewage overflow, a water line break, a chemical spill, a natural disaster such as a hurricane or flood, or some other unusual event. Please check with your local government for the status of boil water advisories in your area.

If your public water system issues a Drinking Water Warning, it means the water in your area is definitely contaminated. Your family members could get very sick if they drink the water or use it to cook food.

Instructions for businesses

How to purify bacteria-contaminated water by boiling:

  • Bring water to a rolling boil and keep it there for at least 1 full minute. Then, let it cool before using.
  • Stop using appliances and equipment that use drinkable water, such as dishwashers, icemakers, tea brewers and coffee makers.
  • Use disposable paper, plastic or foam plates, cups, forks, etc.
  • Prepare food using water that has been boiled.
  • Wash hands with water that has been boiled and cooled.
  • Wash, rinse and sanitize pots, pans and other equipment with water that has been boiled and cooled.
  • Brush your teeth with either boiled or bottled water.

How to purify bacteria-contaminated water with bleach

If you can't boil contaminated water to kill impurities, you can use bleach:

  • Use unscented liquid chlorine bleach containing 4 to 6 percent available or free chlorine. ("Free" chlorine has not combined with organic matter and is therefore available for killing bacteria and algae.)
  • Add 1 teaspoon of bleach to every 4 gallons of water.
  • Let the treated water stand for 30 minutes before drinking or for food-related purposes.

Chemical contamination

Never use water that has been or may have been contaminated with chemicals. Do not use it for cooking, drinking, hand washing, pets, etc., until the water has been declared safe by DHEC or your local water authority.

Private wells

If you use a well you will want to make sure that it is not contaminated with bacteria. Do not use the water from your well until it has been tested. For information on how to have your water tested and your well disinfected, contact your local Environmental Affairs office. For more information, see DHEC Residential Well Disinfection (PDF) or view Emergency Well Disinfection .

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