Disaster Preparedness and Purifying Water

Thanks to Hurricane Sandy, the East Coast is really taking a beating from the weather, making this an important time to review how to use Clorox® Regular-Bleach (and New Concentrated Clorox® Regular-Bleach) for emergency disinfection of drinking water.  It’s not always practical in an emergency situation to boil water for 1 minute to make it safe to drink (especially if you are one of the 5 million people without any power right now, or the 1.5 million people who have been evacuated).  Here are some things to remember when treating water with Clorox® Regular-Bleach:


  • Prior to addition of the bleach, it’s important to remove all suspended material from collected water by letting it settle to the bottom or by filtration.  This means that after you collect some water that hasn’t been treated, you need to let it sit long enough to let any debris settle to the bottom of the container.

  • Next, decant the clarified contaminated water into a clean container, then add the bleach.  Use the table below to determine how much bleach to add—it depends on how much water you are treating.

  • Allow the treated water to stand for 30 minutes.  Properly treated water should have a slight chlorine odor.

  • If there’s no chlorine odor, then you need to repeat the treatment.  Just add the same amount of bleach, and wait for another 15 minutes.  Check again for the chlorine odor before drinking the water.






























Amount of Clear WaterAmount of Clorox® Regular-BleachAmount of New Concentrated Clorox® Regular-Bleach
1 quart2 drops2 drops
1 gallon8 drops6 drops
2 gallons16 drops12 drops, or 1/8 teaspoon
5 gallons40 drops30 drops

Here are some other important things to remember.

  • ONLY use Clorox® Regular-Bleach or new Concentrated® Clorox Regular-Bleach.  DO NOT use the Scented bleaches, High Efficiency bleach Splash-Less bleach, Ultimate Care bleach, or the Bleach Pen.

  • Use bleach that was purchased in the last 4 months.

  • If the water you want to treat is cloudy and you can’t decant or filter it, add twice the amount of bleach recommended above.

  • Check with your water service provider to confirm that your tap water is safe to drink.

  • If you stocked up on bottled water, save the empty bottles!!  You can use some of them to collect untreated water, and others to store the water you treat.

Posted by Dr. Laundry 0