The Ugly Part of Water Purification: Top 5 Mistakes You Make

Water is part of the survival triad – water, food, shelter.

You can only live for about three days without it and even after twenty-four hours, you start experiencing physical and cognitive decline.

Right now, it’s easy to turn on the tap and get fresh, clean water, but even without a SHTF situation, many of us are doing what we can to live off the grid. I’ve written several articles on collecting rain water and purifying water, and now I’d like to discuss how to make sure that your water is safe to drink.

Water purification is a primary skill that you need to have even if you don’t know much about other facets of survival because if you don’t have clean water, you’ll die. It’s that simple.

The EPA warns that as much as 90 percent of all of the water on the planet is contaminated in some way, so this is becoming a bigger issue for many of us who are trying to go off the grid. Even rainwater can be contaminated, and it’s best to assume that all ground water needs purified.

Even though being able to purify water during daily life and in an emergency situation is critical, you need to do it right. Improperly purified water can be just as fatal – but much more miserable – than having no water at all, so be sure not to make these mistakes.

Mistaking Water Filtering and Water Purification

There are many water filters out there; there’s a good chance that you have one in your fridge right now. But don’t make the mistake of thinking that filtered water is the same as purified water. Most water filters do exactly what they say: they filter out physical impurities such as debris, minerals, and pollutants such as insecticides. Most of them don’t purify the water, though, because illness-causing microbes are too small to be caught in the filter, nor are the filters designed to kill them.

This Device Easily Turns Air Into Water!

Your water may look clean and clear and delicious, but it may also be deadly. There are only two ways to ensure that your water is pure – heat and chemicals.

Not Getting Water Hot Enough

Though pathogens start to die as the water heats, at 160 degrees F to be exact, there are many disease-causing bacteria and viruses that won’t die until the water reaches the boiling point of 212 degrees F. Keeping that in mind, you need to maintain a rolling boil for at least one minute, and three is better, especially at higher elevations.

If you’re short on water and worry about losing it to evaporation, putting a lid on the pot will help with that. Then just leave it covered until it cools.

Using Chemical Purification Incorrectly

There are a few ways that you can mess up chemical purification. First, you can use too much. This is most definitely not a case of more being better because whether you’re using iodine, sodium hypochlorite (bleach) or calcium hypochlorite (pool shock), too much of it can make you sick or even kill you.

  • If you’re using iodine, use 5 drops/quart for clear water and 10 drops/quart if cloudy
  • If you’re using bleach, use 5 drops/quart for clear water and 10 drops/quart if cloudy
  • If you’re using calcium hypochlorite, dilute a teaspoon of the powder in a gallon of water, then add 2/3 ounce of that to a gallon of water. A small shot glass is useful because it usually holds one ounce.

There are also a few things to keep in mind when choosing your water purification method. Liquid bleach has a shelf-life of six to twelve months, so it expires and loses its strength. Pool shock keeps forever and a one-pound bag will treat 10,000 gallons. Iodine makes the water taste weird, but if you let it sit for an hour, you can add vitamin C (Tang drink mix or something similar) to eliminate most of the bad taste after the purification period is up.

Make sure that if you’re using bleach or pool shock that the product is pure without any additional additives such as perfumes. Let the water sit for at least 30 minutes before drinking.

Cross Contamination

This one seems like it may be simple, but it’s easy to re-contaminate purified water. Make sure that you don’t use the same containers or utensils for the clean water that you used before it was purified. In other words, don’t gather the water from a stream in your water bottle, boil it, then put it back in your bottle. You just re-contaminated your water and wasted time and fuel.

If you’re purifying in your bottle, make sure to pour some of the chemical into the lid and around the threads/ mouth of the container.

Failing to Purify AND Filter

This is another reason that you need to understand that filtering and purifying are two different processes. You need to filter your water to rid it of illness-causing pathogens, but you need to purify it to remove chemical toxins such as fertilizers and insecticides.

Of course, it also removes any other debris such as sand, rocks, and minerals. It doesn’t really matter what order you do it in, but I’d recommend filtering first then purifying just because it’s cleaner and there’s less risk of cross-contamination.

Either way, strain water that has visible debris in it before you purify it or filter it. Run it through a coffee filter or a densely woven cloth such as a bandana. Just a note: chemical purification is most effective if the water is at least 60 degrees F.

Studies show that at 50 degrees, only 90 percent of Giardia cysts were inactivated after thirty minutes. Warm up the water in the sun (or after it cools a bit from purifying), or let the water sit for an hour.

Failing to purify your water can cause such diseases as cholera, E.coli, rotavirus, hepatitis, staphylococcus, cryptosporidium and Giardia. These cause everything from upset stomach and cramps to severe vomiting, diarrhea, and even death. In other words, it’s nothing to mess around with, unless you want to die a slow miserable death.

Don’t put your life at risk! You need only clear water to stay safe!

Written by

Theresa Crouse is a full-time writer currently living in central Florida. She was born and raised in the hills of West Virginia, where she learned to farm, hunt, fish, and live off the land from an early age. She prefers to live off the grid as much as possible and does her best to follow the “leave nothing behind but footprints” philosophy. For fun, she enjoys shooting, kayaking, tinkering on her car and motorcycle, and just about anything else that involves water, going fast, or the outdoors. You can send Theresa a message at editor [at]

Latest comments
  • Excellent information!

  • This is not specific to your article, but it would be nice to print these articles for a bug-out library, but all that prints is headers and pictures. Am unable to figure out how to format it to print. Any advice would be nice. Ben Simpson Lenoir, NC Got years of survival posts and no way to prep print!!!

    • You need to highlight the article and copy and paste to a program like word. Then delete all of the unnecessary content and save.

      • Thanks for the help. My wife will help me do this.

        • Ben, If you hit F9 on your keyboard, the text will be formatted nice for printing. Select F9, then from your menu, FILE, PRINT PREVIEW, then select your printer.

    • You can highlight the text and copy and then paste to notepad and then print

    • Copy and paste it into your own paper. Then print it.

    • Hi not sure if you sorted this but at the end of the article is a PDF Icon, open as PDF and print.

      Regards Duncan

  • I cannot find anything but concentrated bleach. The only regular strength liquids I can locate are generic store brands. Do the same rules apply for concentrated Clorox?

    • It used to be that Clorox was 8% sodium hypochlotite. Now, it is 6% with the lie on the label, “concentrated”. Some generics are still 8%. READ THE LABELS. Do not use “no splash” bleach or perfumed for water purificaion. Use EPA recommended bleach dosages, for 6% or 8%. Filtering the water first reduces chlorine chemical reaction with debris, that produces chloramines & carcinogens. Filters can become a cesspool of biological contamination, as there is plenty of debris to live off of. Change filers highlly contaminated water areas. Boiling is truly excellent to kill bacteria & ameba, at low altitudes.

  • Good infor in all but not complete. You must talk about the actual size of viruses in order to measure if a particular water purifyer meathod would protect you against said virus. My Methos states purifucation down to 0.01 mincrons. That is more than enough to eliminate all human viruses and bac I would find in post disaster water.

    • The main concern with filters is that you never know when they fail. Did it work? Is the water safe?

    Reminds me of growing up dirt poor in connecticut. we lived in a barn, my sister and i slept in the hayloft. one of my chores was to gather a bucket of water from the river that crossed our property in back of the barn. the river water was well populated by all sorts of swimming critters, including the occasional frog. my grandmother would boil the water for 20 minutes to use for cooking and drinking – boiled critters of every size and imagination and all. if it was in the water bucket, it got boiled. i have no recollection of any of us becoming ill after drinking grandma’s boiled water. she boiled everything – potable water, clothing, chickens, hamburger – you name it. as a widow, she raised her 13 kids during the great depression and knew a thing-or-two about getting the most use out of anything.

  • Hello, Theresa C – I Always enjoy your articles and I Always Learn something from them. Everyone ALWAYS makes the creation of pure (Safe) Water to be Much More Complicated than it needs to be. OK, I opened my big mouth – Here it is . . . FIRST – ALWAYS run your water (Slowly) through an “Activated Carbon” Filter (Pure Charcoal OK) – NO SHORTCUTS here ! NEXT – Boil the water into STEAM and (Use Tubing) and thusly Condense the Steam. Thats it ! If you Boil the water, but Do Not Use an Activated Carbon filter, Then you have just permanently Activated and Energised ALL of the Organic Metallic compounds, and MOST of the Inorganic Metallic compounds ! You Cannot change them Back ! About 70 – 80 % of these are Seriously TOXIC. Of Course, Steam (200 Deg.+ F.) Will Kill ALL Living Organisms. Be Careful when Handling Steam..

  • Thank you

  • Ben Simpson, try out the CleanPrint extension if using the Chrome browser.

  • Thanks for a Great article! Sorry, I tried to take out the caps but the box seems formatted for caps. I do have a question about water taken out of the air. Just how much purification will it need? Water taken from the air is obviously already as clean as the air; after all you’re breathing it as you remove it. If you can breath it without harm, isn’t it ok to drinK?

  • I’ve heard warnings about simply boiling water sometimes resulting in turning water impurities into a more concentrated form of the same making the water worse if anything. This is rarely ever addressed. Why not?

  • So you need to filterall water before purifying it with bleach or pool shock, even if there isn’t noticeable debris in the water?