February 26, 2017

Methods of Water Purification

Methods of water purification

It has been some time since I covered water purification, so I thought it was due. Water is probably the most important of the five basic human needs (water, food, shelter, energy and security) that will be taxed in a disaster scenario.

After the earthquake in Haiti, far too many people died from Cholera because of dirty water supplies. You might be thinking that their supply wasn’t the greatest to begin with. Think back to Katrina. The flooding was so bad that the water supply wasn’t safe. I believe it was Budweiser who shut down a plant and started bottling water to send to victims.

I’ll list all of the ways I know of, with their pluses and minuses, to purify water. If you can think of others, please add them to the comment section.

Out of all other methods, a water purifier is the only method that will not only kill bacteria and viruses, but will remove chemicals as well.

There are several styles of purifiers, and they are not all created equal. I cover many of them in Types of Water Purifiers and Their Applications. There are some filters that are marketed as purifiers. The difference is that filters filter out bacteria and cysts but not viruses. Purifiers filter out bacteria, cysts and viruses, as well as chemicals, prescription meds and on and on.

I recommend a ceramic water purifier and believe them to be the top of the line in terms of purification. Homespun Filters sells these types of filters at a far reduced cost ($33 for a US made filter kit) than you will find anywhere else. They’re able to do so because they sell kits so you can make your own water purifier.

I personally believe that a purifier should be the primary means of water purification. But as the motto states; “Two is one, and one is none”, knowing other methods, and having redundant purification is a good idea.

Bleach is cheap, easy to store and will leave your insides whiter! If you use this method, make sure to use unscented bleach. Bleach will kill pathogens, but doesn’t filter out debris or chemicals.
1. Use bleach that does not have an added scent (like lemon).
2. Add 1/8 teaspoon (8 drops or about 0.75 milliliters) of household liquid bleach to 1 gallon (16 cups) of water.
3. Mix well and wait 30 minutes or more before drinking.

If water is cloudy:
1. Use bleach that does not have an added scent (like lemon).
2. Add 1/4 teaspoon (16 drops or 1.5 milliliters) of household liquid bleach to 1 gallon (16 cups) of water.
3. Mix well and wait 30 minutes or more before drinking.
My biggest problem with this method is that you’re drinking bleach. I know it is diluted, but it is still bleach. Don’t get me wrong, in an emergency if the only water source was a river and my only option was bleach, I would put a pillow case over a pot, and pour water through the pillow case into the pot, then treat the water with bleach. But God gave me the foresight to prepare ahead of time, so I can have another primary method. Bleach also degrades over time, so I would only consider it effective for six months to a year.

Where I can see this method being very useful is if large amounts of water needed to be purified for a large group of people.

Chlorine has been used by municipalities for a very long time for water treatment. Chlorine, like bleach, is a toxin, but diluted enough to be “safe” to drink. I feel the same about chlorine as I do about bleach, with the exception that I have been drinking tap water from a municipality all my life and haven’t keeled over yet. Seriously though, I do wonder what effect the chemicals used to make our water safe have on us long term.

I got an email recently about using pool shock for water purification and had to say I didn’t know anything about it. I did a little research and found this article on the topic.

The article goes over High Test Hypochlorite (HTH) (pool shock) as well as some other forms of chlorine. The positives of HTH are that, stored correctly, it will last longer than you and it is cheap. The down side is that if it gets wet it will off gas chlorine and can corrode metal.

Not all HTH is usable. Buy pool shock without algaecides and fungicides. More safety precautions have to be taken with this method than any other. See the linked article for more information and suggestions.

Because of the shelf life, I would consider this before bleach as a means to purify lots of water fast. I would probably want to let it sit for a day or two and let the chlorine off gas from the water some as well.

Purification tablets

The active ingredient in water purification tablets is often chlorine dioxide. These tablets are effective against bacteria, viruses and cysts, such as Cryptosporidium. Depending on brand, one or two tablets treat one quart of water. I don’t know if they leave an after taste. These should be a short-term solution and would be a good addition to a BOB.
Using an ultraviolet purifier will kill viruses and bacteria but will not remove any chemicals or other contaminants. To use this method you will need a container to hold the water and place the UV source directly into the water. The water in that container will then be free of bacteria and viruses. A downside to these is that they require outside power, either from batteries or electricity.
In my opinion this is a great option for backup purification.
Steripen and TrojanUV are two companies that produce this type of purification technology.

Iodine tablets are effective at killing many things except Cryptosporidium. Some people are allergic to iodine and cannot use it for water purification. Iodine tablets will also leave a chemical aftertaste and should be a short-term solution. With the drawbacks of iodine tablets, they’re not my first pick. If it’s a good fit for you then they might be a good addition to your BOB.

This is another one that I have seen a lot of misinformation on. Some people say that water needs to boil for x amount of time. However, according to the Wilderness Medical Society, water temperatures above 160° F (70° C) kill all pathogens within 30 minutes and above 185° F (85° C) within a few minutes. So in the time it takes for the water to reach the boiling point (212° F or 100° C) from 160° F (70° C), all pathogens will be killed, even at high altitude. In other words once water starts to boil, the baddies are dead.

Boiling is the cheapest way to purify water. You need a pot and a flame. It will suffice to do in small amounts, but doing this on an ongoing basis for all consumed water for a family would get old fast.

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  1. Son of Liberty says:

    Good info Chris, especially regarding the boiling water method. I, too, have seen a lot of misinformation published regarding this method; but it’s not has hard as some make it out to be.

    I think the concerns about chlorine and bleach are somewhat over rated. As you point out you’ve drank lots of city water all your life and you are still alive and fully functional. I was a field engineer for an architects office when we put in a municipal water system for a large community (city and rural), and they do put in various chemicals to purify water after filtration, but it is highly regulated, computer monitored, and carefully scrutinized.

    Take care, keep ’em coming, and blessings on you.

    Son of Liberty

  2. Thank you for the “Homespun” referral! I’m so tired of paying close to $100 per filter for my Berkey! What a price difference!
    Blessings to you and Trudee, Nancy

  3. As far as the boiling water suggestion… you are able to boil water in a plastic bottle with no lid in a fire. It does mean you need a way to pull the bottle from the fire but no pot is needed. And unfortunately you can always find a plastic bottle laying around.

    • That’s a good point, thanks for adding it.

    • Carl Rooker says:

      Yes, you can boil water in a plastic bottle. However, I would be very concerned about chemicals being released from the plastics. In a pinch, this would probably be OK, but I would find another method if the need is more than a few days.

      It is possible to.boil water in a wide range of containers. As long as you keep the flames from touching the dry rim, you can even use paper containers (if said container will hold water). There are several types of canvas buckets that hot rocks can be placed in to beat the water. I have seen this done in waterproof hats as well. It would take some work, but if you made a wooden bowl, you can use the hot rock method in it.

      • boiling water in a plastic bottle? Wow. never heard of that, but a long time ago, a friend told me it was possible to boil water in a PAPER CUP on a camp stove. I tried it on our camp stove, & yes, it actually worked. But the top ring around the top of the paper cup, the part above the water line, did get black from the heat. Who would have thunk it possible to boil water in a paper cup?!

  4. thanks for the link to homespun environmental. I have wanted to get the supplies for this system but have waited because of the cost. this looks to be lower priced and I plan to add this to my preps.
    thanks for all the great posts.

    • My pleasure. It is a far lower cost, maybe 1/4th. I plan on purchasing two when the budget permits.

    • So is a berkley-type ceramic filter actually a water “purifier,” rather than a filter? I’d thot of the ceramic ones as a type of filter. Does this mean that SOME but not ALL filters purify water?

      Also, all the ceramic ones I’ve seen are shaped like a cylinder, whereas the homespun ones are shaped like a dome. So does that mean that the actual shape doesn’t make a difference in how they function, altho the shape could affect what kind of container one puts them in?

      Man, if I can get a ceramic kit for $33, I may get 1-2 extras, for either family/friends or for barter

      • the naming gets tricky, because people use them to mean different things. If it removes bacteria, cysts and viruses, then you’re good to go.

        I don’t think the shape would have anything to do with functionality. as long as the water passes through enough of the filter to remove baddies, it could be any shape.

        I have the same thinking, get a couple to barter or in case I need to ramp up production here.

  5. Chlorine, which is great at killing bugs in the water, also kills the good bacteria in our intestines where 80% of our immune system resides. That is why it is good to drink purified water which is reverse osmosis or distilled. If one has no other choice, then chlorine treated water is preferred to dehydration.

  6. Thanks for another good one Chris! About 1.5 yrs ago, when reviewing our stored preps, I realized that we didn’t have nearly enough water stored, although we had filters & tablets. We increased our water supplies significantly, & added bleach & pool shock. & have been thinking about getting a few more filters & tablets, as barter stuff, b/c some emergency or grid down situations, so many ppl are going to be desperately seeking water & ways to make it drinkable, that I think some of these items will be in large demand. Water is so basic to life on this earth.

    BTW, my church is ending my employment w/ me as their pastor. I have a couple warm leads on churches & would appreciate ur prayers for my family & me.

    • I agree, I think people take water for granted, and if the grid goes down, the faucets connected to city water stop. So people will be looking for ways to purify public water sources.

      So sorry to hear about the loss of your job Red, I will pray for you.

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