ad banner

Emergency Water for Preppers Part 2: Purification

Avatar for Gaye Levy Gaye Levy  |  Updated: November 24, 2020
Emergency Water for Preppers Part 2: Purification

This site contains affiliate links. As an Amazon Associate, I earn a commission from qualifying purchases at no extra cost to you. Full Disclosure Here.

While sourcing water, and especially an adequate supply of water, is a challenge, making such water safe to drink is a whole other matter.  There is much confusion relative to the best method to use to purify water.

Is it boiling, filtering, adding bleach, distillation, or something else?  Truth be told, the answer is “it depends”.  Over time, I am starting to believe that the answer you get is dependent upon who you ask and what interests they happen to represent.

Emergency Water for Preppers Purification | Backdoor Survival

In this article, Daisy Luther, responds to the water purification questions posed by readers in a recent Prepper Book Festival giveaway.  Daisy, who is the author of The Prepper’s Water Survival Guide, is not tied to special interests and is diligent in her research.  As I mentioned in Part 1: Acquisition, she is stepping up to answer your questions and hopefully bring clarification to this all important topic of water purification.

So once again, grab a cup or bottle of good clean water and let us begin with Part Two of “Emergency Water for Preppers”.

Emergency Water for Preppers: Purification

While all of the aspects of water preparedness are vital, often the most overlooked is purification. Sometimes people outside the prepping world don’t think about the fact that the water they manage to acquire could be teeming with dangerous bacteria, sediment, and toxins. Today I’d like to address your questions about water purification.

What is the number one water filter you would recommend?

I have two different favorites.

For in-home use, I love my Big Berkey. For any time I’m away from home, I carry a Sawyer mini. We keep the mini in our backpacks, purses, and vehicles and have at least one in our possession at all times – you just never know when you might need to filter water!

NOTE: To help find the right filter for your unique needs, take the quiz:

[v4_product_quiz_wp quiz-slug=’water-filter-quiz’]

What do you think of steri-pens for disinfecting water?

Steri-pens are awesome, because they are small and easy to use. They can purify up to 8000 liters of water.  They work with ultraviolet light and destroy 99.9% of the bacteria, viruses, and protozoa that could make you sick.

The potential downside of steri-pens is that they require a power source. Some, are powered by AA batteries, while others can be recharged by computers, solar panels, or a wall charger.

What do you think of the SODIS method of purifying water?

SODIS stands for solar water disinfection.

It’s pretty amazing. Put water into a PET plastic bottle (PolyEthylene Terephthalate, Recycle code #1), lay it in the sun for at least 6 hours, and boom – you have safer water. The beauty of the SODIS water purification method is that it costs next to nothing and is simple to do in nearly any location.

The outdoor temperature is irrelevant – the purification occurs from the exposure to UV rays. This is sort of like an off-grid steri-pen.

Some warnings: if the water is cloudy, you need to filter it before using this method. If the weather is cloudy or overcast, 2 days will be required to purify the water.  Be sure that your plastic bottle is absolutely clear.

This method is approved by the World Health Organization, the Red Cross, and UNICEF. (source)

For those who are concerned about the exposure to petrochemicals or BPA in the plastic, the SODIS website says that as long as you use the PET plastic bottles, the amount of exposure to those and other chemicals will be insignificant.

While this might not be my number one choice for water purification, if I was in a situation in which I didn’t have the supplies to use other methods, this would be my fallback method.

Speaking of the SODIS method, you might want to read Gaye’s review of the Puralytics Solar Bag; I know she swears by it.

Is using a WAPI (water pasteurization indicator) really adequate for heating water to a safe enough level to drink?

There are pros and cons to water pasteurization indicators.

On the pro side, a WAPI can help in situations during which you need to save fuel, since the pasteurization point of water is lower than the boiling point. They are a reliable way to heat your water quickly.  Since they’re small and inexpensive, they can be a great addition to a bug-out bag.

This being said, I’d normally just opt to boil my water, since boiling water is unmistakable and can’t malfunction. Rocket stoves take very little fuel to bring water to the boiling point.  WAPIs are really just a matter of personal preference.

What is really the best way to make sure you have clean water: filter, distill, boil, bleach, pool shock?

Distillation is probably the very safest method. When you’re capturing steam, you’ll have no debris or sediment, and the boiling required to make the steam will kill nearly all contaminants like bacteria, viruses, or protozoa.

The problem with distillation is that if water supplies are limited, you lose a lot during the process. This means it’s not the best method for every situation.

Water purification is always two-fold – you have to get rid of the chunks and you have to get rid of anything harmful living in it. If you are not distilling, most often it’s recommended to both filter and purify.

How do you use pool shock for potable water?

The great thing about storing pool shock instead of bleach is that you don’t have the limited shelf life of bleach. When a prep is this vital, you want it to be at full effectiveness when you need it the most.

Before using pool shock or any chemical purification method, filter any debris, particles and sediment out of your water.

Gaye has an excellent article with all the details on using pool shock to purify water. In summary, she wrote, “For my own use, I settled on 1 teaspoon of pool shock per gallon of water when making up my stock chlorine solution.  Then, to disinfect water, I used 3/4 ounce of my pool shock solution to treat a gallon of water.  This makes it easy to calculate how much to use, regardless of the size of your container.”

Always, always use eye protection goggles and gloves when dealing with caustic chemicals. If your water tastes funny, you can aerate it by pouring it back and forth between containers a few times.

How do you filter iron and sand from well water?

Reverse osmosis is one of the best ways to remove unwanted minerals from any kind of water, but in an off-grid scenario that isn’t going to do you much good.  Not only are most RO systems grid-dependent, but they can also be outrageously expensive.

Carbon block filters (like the kind in the Berkey systems) are your next best option for removing sediment. The more sediment in your water, the more frequently you’ll need to replace your filters. Be sure to stock up on lots of extras.  Berkeys are gravity fed and require no source of power to clean your water.

I have looked at my water heater as a 50-gallon source but our water has a lot of minerals in it.  What is the best way to clean it up for consumption?

When harvesting water from your water heater, quite often the first water that comes out will be discolored and full of sediment. Reserve this for non-consumption uses like flushing the toilet. (Regularly flushing your water heater will help keep the sediment from building up too much.) Once the water runs clear, you can collect this for drinking water.

Once you’ve collected the water, you should still purify it and filter it through something like a Berkey filter to remove any debris.

If you have a heavy buildup of lime, calcium, or other minerals, the best method for making the water safe to drink is distillation.

My question is how to make an easier homemade distiller for water. This would be helpful if one can afford a fancy distiller, but still has concerns about water quality in a less than ideal situation.

Gaye has chosen to answer this one so let me turn things over to her:

I was lucky enough to receive an advance copy of Jim Cobb’s newest book, Prepper’s Survival Hacks.  In it he addresses the question of how to build your own solar still.  Even though his book is not slated for publication until mid to late September, both Jim an his published have granted me permission to share his hack for building a survival still.

And just so you know, I agree 100% with Jim.  This is not something I would do when SODIS or some other method is more productive.


I’m going to be flat-out honest with you. I don’t in any way, shape, or form endorse the use of a solar still for acquiring water in a survival situation. I’m including it here for two reasons.

1. In any survival manual, it is almost expected that the solar still be mentioned, and its absence in this book would be noticeable.

2. I wanted to include it specifically so I could talk a bit about why you shouldn’t rely upon it.

Bucket or clean container
Large plastic tarp
Large rocks or logs
Small rock

#1  On the surface, the solar still is a fairly straightforward project. Using your shovel, dig a hole a few feet deep. At the bottom of the hole, roughly in the center, place your bucket or other clean container. Next, stretch the plastic tarp across the top of the hole using the large rocks or logs to secure it in place. Finally, place a small rock at the center of the tarp, which weighs it down above your container.

#2  The idea is that the sun will heat up the inside of that hole, causing moisture from the ground to evaporate, then condense on the bottom of the plastic tarp. It will then run along the plastic to the point above the bucket, into which it will drip.

Here’s the thing. The amount of water you’ll gain through the use of the solar still is, quite literally, a drop in the bucket compared to the amount of energy you’ll expend by digging the hole and setting everything up.

Don’t believe me? Go ahead, set one up tomorrow and see how well it performs. If you get more than 2 cups of water, you’ll be doing fairly well.

What would you recommend for a budget conscious first water filtration system?

If you want one of those pricey systems but can’t afford it, you can actually build your own version of a gravity filtration system. All you need are some basic tools, a couple of food grade buckets, and 2 or 4 Berkey filters.

I have not made this myself but have been present when someone else did, and it absolutely works like a Berkey. We did the dye test after he made it and the DIY system passed.  This is a good short term solution.

When you can manage it, I recommend upgrading to a ready-made high quality filter made with stainless steel, but this will get you through in the event of an emergency.


The Final Word

Sometimes the pursuit of knowledge results in more questions than answers.  I hope that is true in this case because the more you ask, the more you learn.  The more you learn, the better prepared you will be following a disaster or other disruptive event.

Going forward, there will be an article answering your questions about water storage (Part 3 Emergency Water for Preppers: Storage) as well as a round up article providing you will links to some of the best articles on the web written by my preparedness blogging colleagues.  Plus, in case you missed it, here is Part 1, Emergency Water For Preppers: Acquisition.

As I mentioned in Part 1, one thing you can count on is that over time, I will continue to introduce you to strategies and resources that will help ensure that you have an adequate supply of water to help you maintain both hydration and sanitation, no matter what.

Enjoy your next adventure through common sense and thoughtful preparation!

If you enjoyed this article, consider subscribing to email updates.  When you do, you will receive a free, downloadable copy of my e-Book, The Emergency Food Buyer’s Guide.

You can also vote for Backdoor Survival daily at Top Prepper Websites!

Below you will find the items related to today’s article.

Sawyer Products Mini Water Filtration System: Fans of the Sawyer water filtration systems are evangelistic in their praise.  Did you know they only weight 2 ounces and fit in the palm of your hand?  The price is right.  Be sure to also check out the Family Color Coded Gift Pack which looks nice.

Berkey Water Filter System:  I personally own a Royal Berkey and it represents a key component of my water preps.   This is definitely something you want to save up for.

Puralytics SolarBag Water Purifier: I reviewed the Solar Bag last year and cannot say enough good things about it.  This is by far the easiest way to purify water using the sun.  It even works on a cloudy day; it just takes longer.  Here is my review: The SolarBag Water Purifier.

SteriPEN Adventurer Opti Handheld UV Water Purifier: This is the UV version of the SteriPen.  It is compact and portable and those that own them, love them.  I admit, though, that I have not used on myself.  There is also this USB powered model that can be powered with a portable solar panel.

Puralytics SolarBag Water Purifier: I reviewed the Solar Bag last year and cannot say enough good things about it.  This is by far the easiest way to purify water using the sun.  It even works on a cloudy day; it just takes longer.  Here is my review: The SolarBag Water Purifier.

DryTec Calcium Hypochlorite, 1-Pound:  This is 68% Calcium Hypochlorite.  As of this writing, the price is with free shipping.  I purchased Ultima Pool Shock which is 73% Calcium Hypochlorite.  For more information, read How to Use Pool Shock to Purify Water.

3M TEKK Protection Chemical Splash/Impact Goggle:  I am pleased with these eye protection goggles and the price is reasonable.  I have stashed them in my “water box” as well as in my tool kit, sick room kit, and bug-out-bag.

Prepper’s Survival Hacks: 50 DIY Projects for Lifesaving Gear, Gadgets and Kits:  You are going to want this book,  Written by my trusted colleague, Jim Cobb (and I know you LOVE his books), you are going to find his projects are a well thought-out resource you can actually use.  No fluff here.

The Prepper’s Water Survival Guide:  You can survive up to three weeks without food, but only three days without water. When catastrophe strikes, having enough water can spell the difference between life and death. This book offers a step-by-step plan with straightforward information you can easily follow.  Written by my friend Daisy Luther, I recommended the book for everyone’s survival library!

LifeStraw Personal Water Filter:  The LifeStraw is considered the most advanced, compact, ultra light personal water filter available. It contains no chemicals or iodinated resin, no batteries and no moving parts to break or wear out. It weighs only 2 oz.  making it perfect for the prepper. For more information, see my LifeStraw review.  There is also the LifeStraw Family that can be used to filter 9 to 12 liters per hour.

Potable Aqua Water Treatment Tablets: Potable Aqua Water Purification Tablets make questionable water bacteriologically suitable to drink. Easy to use and the water is ready to drink in 30 minutes. One 50 tablet bottle treats 25 quarts of water.


Help support Backdoor Survival. Purchases earn a small commission and for that I thank you!


Aff | Emergency Survival Blanket

[DEAL] Emergency Survival Blanket

Pocket-size survival blanket could save a life - throw in your bag or car.

Get Cheap Security
Aff | Emergency Survival Blanket
[DEAL] Emergency Survival Blanket Get Cheap Security

10 Responses to “Emergency Water for Preppers Part 2: Purification”

  1. I had an interesting read! This is great! I use Big Berkley too. I believe that filtering water before drinking is the safest action we can make to ensure safety.

    Please check us out online:

  2. Didn’t you get a water still to try out? What are your thoughts and findings with the emergency water still?

    • I did. My emergency water still is an important part of my preps because I want to have the ability to create drinkable water from salt water. I am embarrassed to say it is still tucked away in it’s box in my garage.

      That said, the focus of this article was reader questions and answers. Hopefully I will find time to test my emergency water still soon so that I can report back with my findings.

  3. You may not know that Berkey filters cannot be sold in California or Iowa, as they make purification claims that those states’ consumer protection agencies will not accept without further testing. Given this, what would be your #2 choice for in-home use? Thanks!

    • Please see my comment above about the Sawyer Point Zero Two. Also, for my money if 48 out of 50 (or is it 57?) states allow the Berkey, I would go with the odds. I’m not sure what authority California and Iowa claim to limit sales, but it sounds wrong. Berkeys are pretty, they’re expensive, they work …. but there are alternatives …. if you shop, you can find several.

    • you might check out the lifestraw family system. it filters a boatload of water, and unlike the lifestraw personal filter, also filters out viruses.

    • Right teabag …. I am familiar with the Lifestraw Family and have one tucked away. One additional feature of the Sawyer is that it can be fitted to a 5 gallon or larger container for raw water and can operate unattended for an increased time (time used to chase marauders off the property).

  4. Anyone from Ky, worth his weight knows how to make a cheap, easy, distiller. Everyone has a canner for canning their mators. Unscrew the do-hickie that jiggles on the lid, and screw in the fitting that goes on the end of a roll of small copper pipe. Lowes has a 10 foot roll of copper pipe pretty cheap. Attach this roll of pipe to your canner. Fill you canner about 3/4 full of water, or what ever. Place it on your rocket stove and coil the copper pipe in a 5 gallon bucket full of water. Heat. Collect the water coming from the end of the pipe. Drink and be happy. If you dont like water, (it will rust your internal pipes) put in a mash that has been setting around somewhere for 21 days of 8 pound of sugar, 7 pounds of ground corn, and a little yeast. Run this through your canner. You wont worry about the world coming to an end. PS. Dont worry about your ears ringing. This is a natural occurrence.
    Some folks will worry about using aluminum for boiling water, but “still” makers have scientific evidence that this is not harmful.

  5. I have purchased what I believe is the cat’s meow of water purifiers … the Sawyer Zero Point Two. I got one from for less than $100. It “filters” down to .02 microns which includes all bacteria, all protozoa, and a good number of viruses. The filter is rated by Sawyer for 1 million gallons …. more than I will certainly need. I highly recommend this small and lightweight addition to your preps.

Leave a Reply