You can only carry or store so much water. What happens if you lose access to water for longer than a few weeks/months? What then?
Long-Term Water Shortage?
You will need to find an alternate source of water. Jodi and Julie over at Food Storage Made Easy have a fantastic article on this topic: Alternate Water Sources. I suggest you print it out and add it to your emergency grab and go binder.
Once you’ve found an alternate source of water, you will need a way to make that water safe to drink. The purpose of today’s post is to teach you how to do that.
Water filtration vs water purification
But first, you need to understand the difference between water filtration and water purification. This can get a bit tricky.
Filtration
Filtration is what it seems to be. A system that filters out unwanted “stuff.” It is like a giant strainer and anything too big to pass through the strainer is kept out of your water. This (obviously) includes things like debris, sand, dirt etc. With a good filter, this also includes all bacteria and protozoa.
This level of “water cleansing” is sufficient for most water you will find in North America. This would also be sufficient for water you have stored in your home if you are unsure of its safety.
However, water filters miss one thing: viruses. The viruses are simply too small and they pass through the “strainer.” With most water sources that aren’t exposed to sewage, this isn’t a problem. However, it could be more of a problem in a long-term disaster situation.
Purification:
Water purification typically uses a chemical treatment (UV light is one approach) to eliminate (kill) viruses as well as bacteria and protozoa.
However, if all you do is purify your water, it may be safe to drink, but still, contain sediment or other nasty looking “stuff.” (sticks, sand, dirt etc)
If you want your water to both look and be safe to drink as well as taste good, you want to purify and filter it.
The confusing part:
Now comes the confusing part: While many filters and purifiers are labeled as such, not all are. Some products that are labeled as purifiers are just purifiers, but others will both filter and purify. The same goes for products labeled as water filters. Some are just filters. Others will both filter and purify. So, make sure you read the fine print so you know what you are getting! If it removes bacteria and protozoa, but not viruses, then it is just filtering your water. If it removes bacteria, protozoa, and viruses, you will have purified water.
I’ll help you out by listing various processes and some of my favorite products below:
Products or Processes that ONLY PURIFY:
1. Boiling waterHeating water to 150 degrees is often recommended or suggested. Many call this pasteurization since that is the temperature at which milk is pasteurized. This temperature will kill all protozoa. But higher temperatures (or longer periods of time) are needed to kill all bacteria and viruses. I suggest you will boil water (212 degrees Fahrenheit) for 1 full minute to make certain it is truly purified. Source: Health.ny.gov |
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2. BleachHousehold bleach (chlorine) can be used to purify water. Simply add 1/4 tsp (8-12 drops) to 1-gallon water. |
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3. Chlorine DioxideThis is a good product to use GERMISEP Disinfectant Tablet 2.5G 100 Tablets. |
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4. UV Water PurifiersUltraviolet light can be used to purify water. The most common, well-known brand (and the brand I use) is the SteriPen. |
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Processes or Products that ONLY FILTER:
There are numerous options for water filters available. I’ve listed my two favorites and then a general type of filter below, but you may find others that work for you. Just remember that if it “filters” viruses in addition to protozoa and bacteria, it is actually combo filter/purifier.
1. Sawyer Mini Water FilterThis tiny (2 oz) filter can filter up to 100,000 gallons of water. Find it on Amazon here. |
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2. Sawyer 3-Way Inline Water FilterI like this filter because I can attach it to my faucet. If our water were compromised but running, we could keep life relatively normal by attaching these to one or more faucets in our home. Find it on Amazon here. |
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3. Pump FiltersThese filters can be used to pump water out of any source (lake, river, 55-gallon barrel). There are many brands available. I have only used Katadyn’s, but I’ve liked them. Find them on Amazon here. |
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Processes or Products that FILTER AND PURIFY:
These products do both jobs (filtering and purifying) at once. They are AWESOME!
1. Berkey Water FiltersThese are HANDS DOWN my very favorite product listed on this page. They are top rated and easy to use. You can’t find a bad review out there. They come in sizes small enough to fit in a go-bag / 72-hour kit and have sizes large enough to hold/purify six gallons in 30 minutes (crown Berkey)! Find them here. |
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- Various sizes available
- Incredibly fast: 42 – 288 gallons / day!
- Includes a spigot so these can be used at a sink similar to a faucet.
- Each filter (you can have 1-4 per system) filters 3000 gallons.
- If you have a pump for your 55-gallon barrel, you could pump directly from your barrel into the top container on your Berkey
- Gravity does the work for you. No need to pump, suck, squeeze etc. Just pour water in the top and it comes out the bottom clean.
- Average cost per gallon at around $0.02 / gallon purified.
Disadvantages:
- Initial cost is higher than the other three options I’ve listed here: The smallest one (go-Berkey) is $150. The largest is $325. Replacement filters are $50-$60 each.
2. Seychelle Water Filter PumpI like this filter because I can attach it directly to my 5 gallon and/or 55-gallon barrels. Find it on Amazon here. |
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- Pumps and purifies water at the same time directly from a 55-gallon barrel.
- Lowest initial cost of all four options listed here. It retails at over $100, but can often be found on sale for $40 – $50 on Amazon.
Disadvantages:
- Will only filter 150 gallons before you need replacement filters which cost around $20.
- High cost per gallon at around $0.03 – $0.06
- Since it only filters 150 gallons, it could not really be counted on for a long-term water shortage unless you also bought a lot of replacement filters.
Would not work in a go-bag / 72-hour kit
3. Sawyer Complete 4-Liter Dual Bag Water Purifier SystemThis filters up to 1 MILLION gallons of water! Find it on Amazon here. |
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4. Lifestraw Family 1.0This filter/purifier is a great bang for your buck. Find it on Amazon here. |
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There you have it! Water Filtration vs Water Purification! What systems do you have/want?
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Thanks for all of the information about water conditioning. I like how you showed all of the different filter types, and listed their advantages and disadvantages. We’re looking to purify our water to be more healthy, so I’ll have to look into these some more.
For 25 years we have used rain water, but A) it must be in a concrete or galvo tank so wild fires wont burn it. B) Automatically or manually divert the 1st half hour of rain in order to clean both the air & the roof etc. The tank water is just for cooking, drinking + dish wash-up. We also have a small dam below the water table for garden, cleaning , laundry etc. Clean the car when it rains, also probably do laundry rinsing- – –
Great post. Natural and safe water is not easily accessible at present across the world. So everybody needs a good water purifier. https://www.ewaterpurifier.com/
Thank you so much for the valuable explanation. This really illuminates my understanding about water purity in general.
Yay! Glad to hear it Phuong!
What’s the recommendation for stored water? Do you put bleach in with the water when storing or put it in right before you’re going to use it?
Sorry for the late response here Kelle. HERE is an article I wrote that answers all that!
We actually have 3 systems going for us. The first is the Sawyer Point One mini in each of our GO bags. I’ve used mine on numerous trips and campouts and it does an amazing job cleaning the water. The big selling point for me was that it screws onto standard water bottles (which I find trailside ALL the time) or a tube. Water bottles hold up to squeezing MUCH better than the bags do.
We have it’s big brother set up for bucket filtering. We have 2 buckets pre-drilled with all the attachments, filters, tubing, directions and pictures of it set up to use at the house with our stored water supply, “found” water and municipal supply.
Lastly is the Sawyer Point-Zero-Two filter which filters viruses as well. That is kept in reserve (due to cost) but can be used in place of the other filters without having to adapt anything.
One thing to note, we made a gravity system using 2 inexpensive bladders from wally world (I think they’re Outdoor Products brand). We wrapped one in black tape to identify dirty water and took the bite valves off each one and put the Sawyer filter inline, connecting the 2 bags. The dirty one gets filled (bandanna over the opening to remove large debris and most sediment) and then hung on a tree. In no time, the other bag is full and ready to go.
I was sold on Sawyer products when I used them in the military ages ago. There was some definitely NASTY water in the countries we went to and that little filter kept me safe time and time again. Add to the fact all the good humanitarian deeds they are doing to provide clean water around the world and my money will go to them every time.
Thanks for putting the course together, it’s a great one!
Sawyer products are pretty sweet Rob. Thanks for the thoughts / tips and for sharing your experience!
Excellent info as usual. I was wanting to buy something but wasn’t sure what to buy…you made it so much clearer. Thanks for all your research…much appreciated.
Well you are very welcome Joyce. I’m glad it was helpful!
Where we live we have well water for the only option, we use reverse osmosis for the house. I was wondering if anyone knew if any of the filter / purifiers would get rid of excess nitrates and phosphates as our ground water and streams are so polluted with pesticides and weed killers for the farmers fields around us.
I know there are filters that remove nitrates though I don’t know much about them (https://www.filterwater.com/s-7-nitrate-filters.aspx?gclid=cju015-j3sucfyqufgodlmqaxa). I’ve never done much research on the topic. But that may be an idea for a new post….(-:
We have a few different filters but I want to get a steripen. One filter that I found to be reasonably priced for emergency long term needs is a Ceramic Water Filter DIY Gravity Drip Filter Kit and is about $36. https://www.getpreparedstuff.com/Ceramic-Water-Filter-Kit-p/ceramic-filter-kit.htm
Thanks for all the info, I hadn’t ever stopped to think of the difference between purity and filtered.
Thank you so much for sharing this information! Never thought about the difference before & now I know. I have been following your Prep 101 since last month & you have helped me be better prepared. I am not overwhelmed & every week I just wait for your “lessons” & I try to complete them to the best of my ability. You are doing an awesome job & helping so many of us be better prepared.
THANK YOU Patti! It is so encouraging to know that the course is truly helpful! Thanks for taking the time to let me know.
You were talking about the twigs and debri. I bought an embroidery hoop and used a very tight woven material to attach inside. I pour the dirty water through it, directly into my Berkey and it works great. Tried it while camping to make sure it would work and it did. Just a suggestion. Great article you presented on all the other avenues. Thank you for sharing.
Smart! Thanks Sue!
Thanks for including SteriPEN! SteriPEN handheld UV water purifiers are also great for when you’re traveling to areas with unsafe water. International travelers can save thousands of dollars by purifying tap water rather than buying bottled water and help the environment by keeping plastic water bottles out of landfills.
The SteriPen is a great tool!
We have a Berkey and a steri pen. I love my berkey. I thought it would be worth mentioning that it also takes out added chemicals such as floride( if you buy the extra filter) which was wjy we chose it as our water purification method.
Yes. It does! I should add that!
I’d also like to see you add a prominent note to make readers aware that not all filters eliminate the hazards of viruses and that all water should be boiled, exposed to UV light (sun) or chemically treated for safety. People think they are safe when they are not.