While bleach is one of my least favorite water purification techniques, it has it’s place in emergency preparedness and is a very simple back-up for water purification. The important thing to know about bleach, however, is that you should not use it if you aren’t familiar with its application. People have killed themselves by adding too much bleach to their water. Hopefully this article educates you to a point that you don’t need to worry about that! Before we get started into the process I want to cover some pros and cons of using bleach to sterilize your water.
Great for short term water purification
Taste – Can be unappealing to some people
Ineffective for long term water storage
Toxic when misused
Dangerous around children
Short shelf life
So now let’s get into the nitty gritty.
You can find bleach at any grocery store. Most household brands contain 5.25% sodium hypochlorite (NaOCL). In order to purify your water this percentage needs to be between 5% and 6% so most brands will work. If you are storing bleach for water purification be sure to get the pure original stuff. Nothing with added scents, colorings or chemicals. If it isn’t pure please, please, please don’t add it to your water!
1 Gallon of Clear Water : 8 drops of Bleach
1 Gallon of Cloudy Water: 16 drops of Bleach
5 Gallons of Clear Water : 1/2 teaspoon of Bleach
5 Gallons of Cloudy Water: 1 teaspoon of Bleach
After adding the bleach, stir or shake the container. Allow the water to stand for 30 minutes. You should smell a slight chlorinated (pool water) odor. If you don’t smell this, add another dosage and wait another 15 minutes before drinking.
As you can imagine the water will have a slight chlorine taste to it. Another issue I have with Chlorine is it’s effectiveness and shelf life. The effectiveness of chlorine significantly drops after 6 months on the shelf. So in all reality you shouldn’t depend on your chlorine for purification if it is over 6 months old.
The other issue is it’s effectiveness. If you add chlorine to your water storage it won’t extend the shelf life of your water. Unless you are using 100% polycarbonite containers, your barrels will still leech into your water and you will still have to purify it when you use it.
So in summary, chlorine is one of my last resort water purification methods. It is very effective for temporary and quick purification. Your kids might not be too happy with the taste but if you have no other method this will work just fine. Safety first and happy prepping!
UPDATE: Based on some comments and emails I’ve received I’d like to address my concerns over leeching and bleach shelf life. My reply to a comment below: “Concerning both – I’ve found that emergency preparedness research is as saturated as the field of diet and exercise. One day we’re told not to eat salt, the next salt is okay. Then eggs are bad, then they’re okay. The research goes on and on without any statically conclusive results. Water storage is similar in regards to the fact that I have found mountains of research seeming to substantiate both the argument that leeching is a legitimate cause of concern and that it’s not. The same goes for the bleach efficiency. So considering that I have yet to be 100% convinced of the safety of leeching or the shelf life of bleach, I have chosen to post a cautious approach for the safety of my readers. I appreciate your comments however and welcome anyone and everyone to look into evidences against these two and make their own judgement as to its safety.”