The amounts of bleach in the tables below are for clear water. If water is cloudy and cannot be filtered or clarified, double the amount of bleach. Allow water to stand 30 minutes. The water should still smell of bleach after 30 minutes. If it does not, repeat the bleach application and let stand another 15 minutes. If you still can’t smell the bleach, discard the water and find another source. The smell of chlorine in the water is a sign of safety, so it is important not to use scented bleach.
| Regular Bleach 5.25% to 6% sodium hypochlorite1 | |
| Water | Bleach |
| 1 quart | 2 drops |
| 1 gallon | 8 drops |
| 5 gallons | 1/2 teaspoon |
| 10 gallons | 3/4 teaspoon |
| 50 gallons | 4 teaspoons |
| Concentrated Bleach 8.25% sodium hypochlorite2 | |
| Water | Bleach |
| 1 quart | 2 drops |
| 1 gallon | 6 drops |
| 5 gallons | 1/4 teaspoon |
| 10 gallons | 1/2 teaspoon |
| 50 gallons | 3 teaspoons |
Bleach begins to lose strength after 6 months and should be replaced after 12 months.
“If you do not have a dropper, use a spoon and a square-ended strip of paper or thin cloth about 1/4-inch by 2 inches. Put the strip in the spoon with an end hanging down about 1/2-inch below the scoop of the spoon. Place bleach in the spoon and carefully tip it. Drops the size of those from a medicine dropper will drip off the end of the strip.”3
1 https://modernsurvivalblog.com
2 https://www.cdc.gov/healthywater/emergency/drinking/making-water-safe.html
3 FEMA