Water Filtration & Purification

*Article taken in part from ThePrepared.com*

You know water is vital to emergency preparedness — you can only survive three days without it — and you probably know it can be hard to get consistent and clean water in a SHTF disaster. You can’t depend on “running to the store” at the last minute or carrying all the water you need. Unsafe drinking water causes half of all the occupied hospital beds in the world and over two million preventable deaths each year. Prepare now and avoid the pain later.

We spent 48 hours researching and reviewing over 70 portable survival water filters for preppers so that you don’t have to — and more importantly, so that you don’t buy a bad product and die.

This review covers the kind of products you’d keep in your go-bags, perhaps with some extras in your home supplies or for everyday carry. These products should be one of your very first purchases in prepping.

Summary:

* Water, especially water affected by emergencies like grid failure or flooding, contains organisms that can make you very sick at the worst possible time.
* Water can be treated in a variety of ways: filter screens, purification chemicals (chlorination), boiling it away and recapturing the steam (distillation), reverse osmosis, UV light, or boiling. Each has its pros and cons.
* We recommend using filters for basic prepping needs because it’s the best way to quickly turn wild water into drinkable water.
* You should have at least two of the filters recommended in this guide in each one of your emergency bags. A mix of different types is the best, because no single product is perfect.
* We recommend keeping 500mL or 750mL (a normal water bottle) of potable water stored in your bags at all times, that way you have something to drink in the immediate aftermath.
* Your personal filter choice might come down to whether or not you care about virus protection. We think about virus protection as a nice-to-have if you can afford it.
* Companies are in an arms race to have the longest filter life. Giant numbers like 200 Kiloliters are under perfect scenarios with clean input water.
* Capacity matters more when we’re judging numbers like 1000L vs 5000L. But once the numbers get really high, they start to matter less.
* There’s no singular perfect mix of products. But do think about how your multiple layers of water treatment products can work together: can you mix and match pieces, do you have vessels for storing clean or dirty water that can attach to your filters, etc.

## How water purifiers fit into emergency preparedness

Following the beginner prepping checklist, there are three main scenarios you plan for:

* Staying home (bugging in or sheltering in place)
* Being able to leave your home at a moment’s notice (bug out bags)
* Being able to get home or get to safety if emergency strikes when you’re away (get home bags and everyday carry)

Even if you’re planning on staying home, one of the core sane prepper rules is that you can’t predict what will happen. So you should be prepared to survive in case you have to leave or never make it home to begin with, making your home Brita filter worthless. You simply cannot depend on being able to buy water at the last minute, use your bathtub, or get free handouts from FEMA quickly enough to matter.

You should have small water containers for short term emergencies filled and stored in your home that cover at least the first two weeks.

There are better water filter systems that make sense for a prepared home or large groups in fixed positions (like the Berkey filters). But those home filters aren’t practical for portable use and should only be taken on after covering these basics.

Redundancy is built into these models. Which also makes it easy for beginners or those on a budget to baby-step their way in. For example, your bug out bag is always packed and ready at home, so even if you do end up staying home during an emergency, you’ll have these portable filters on hand to compliment whatever larger water gear you have on hand.

Water is very heavy at 1kg per litre, plus the weight of the vessel. People need an average of 5L per day — if not more when on foot. So the idea you’ll carry the water you need for days is a non-starter.

But we do recommend you keep 500-750mL of potable water stored in your emergency bags at all times.

Water is so important, you don’t want to be worrying about finding a water source and filtering it in the minutes and hours after SHTF. This probably means having a rigid water bottle in your pack, which may or may not affect which filters you buy.

Even if you don’t buy a filtered bottle below, you still need to have some kind of vessel in your bags, so be mindful about the gear you have or need to carry water and/or cook with it.

Think about cross contamination and how you’ll handle vessels that hold dirty water. Once a vessel holds bad water, you’ll ideally not put clean water in it until you’ve washed it out with soap. Some products below even give you separate “clean” and “dirty” bags.

## Common risks in untreated water

Some people think “I’ve drank from streams before and never gotten sick, so I don’t need this.” There was even a (debunked) article that went viral arguing against the need for filters.

Don’t buy it. This is an important prep to have.

There are three main categories of water risks: sediments, biological organisms, and toxins. More specifically:

* **Sediment**: Solid stuff like dirt, sand, silt, debris, plant and animal matter.
* **Algae**: Green/blue/brown slime that grows in still water. The CDC reports harmful algae blooms are increasing due to climate change and industrial waste.
* **Bacteria**: Namely from human and animal fecal waste, like E. coli, salmonella, cholera, shigella, and coliform.
* **Protozoa**: Larger, more advanced single-cell organisms than bacteria that feed on organic matter, like giardia, cryptosporidium, and cyclospora.
* **Cysts**: These are just dormant forms of bacteria/protozoa waiting to ‘turn on’ once inside your body, but you sometimes see them listed separately in product marketing materials.
* **Viruses**: Hepatitis A, SARS, polio, and HFMD (hand, foot, and mouth disease) caused by viruses like norovirus and rotavirus.
* **Chemicals, heavy metals, & society’s waste**: Countless contaminants like oil, pesticides, cleaning agents, acid rain, industrial runoff, paint, or heavy metals like lead and mercury.

The two most common dangers in developed countries like the US and Canada are **giardia** and **cryptosporidium**, two unpleasant single-celled protozoan parasites that come from animal feces and can cause severe intestinal problems. They usually have more common non-scientific names like “beaver fever.” Cryptosporidium in particular has a hard outer shell, making it difficult to kill.

Viruses are generally not a threat in modernized countries with temperate climates, like Australia, USA or Canada. Water viruses are much more common in developing countries or areas with extreme climates, like Mexico or India.

Running water is generally safer than still water because nature acts like a filter/cleaner as water moves through it.

Non-living toxins are generally more of a threat the closer you are to dense cities and industrial or mining areas. We don’t ever assume water is 100% safe, but water in a remote mountain stream is likely safe from heavy metals and chemicals.

There are no portable survival filters that handle salt water and most won’t handle water-soluble chemicals (like fluoride) or industrial metals.

## Water sources in emergencies

It’s important to be adaptable and not pigeonholed into overly-specific scenarios — easily one of the most common prepping mistakes we see everyday, including when buying water products.

Don’t get tricked by product marketing: Most of you are more likely to be drinking from a dirty urban puddle than a clean mountain creek.

Unfortunately, the sources of water you’d naturally turn to in an emergency are becoming more contaminated every year because of human activity.

For example, even though over 30 thousand tons per year of the top 10 toxic industrial chemicals are improperly disposed of (polluting drinking water across the west), after a successful lobbying effort by the chemical industry in 2018 the US EPA decided to stop considering the effect of toxins in water when evaluating risk.

During most emergencies, water sources and quality will be the same as normal. But larger emergencies can quickly contaminate the water, such as hurricanes, flooding, grid/infrastructure failure, industrial accidents, biological contamination, and major SHTF scenarios.

If a storm floods your city, all of the surrounding water is likely tainted with industrial runoff, auto chemicals, and sewage.

After Hurricane Harvey hit Houston in 2017, the water was so contaminated that people were getting sick just by walking through it. Medical tests showed the water had up to 5,700 times more bacteria than EPA standards.

Only 3% of sewage treatment plants in the Houston area were affected, but that was enough to massively contaminate the whole region — let alone all of the flooded dry cleaners, industrial plants, auto body shops, and so on that released “millions of pounds of pollutants”.

The risks are meaningful. A bout of gastroenteritis or Legionnaires disease will really make your bad days even worse. An emergency is not the time to be broken down from fatigue, diarrhea, and vomiting.

## Best personal water treatment method for prepping

Each method has pros and cons — and no single method will make water 100% safe — but in the end we recommend filters for your basic prep supplies.

There are multiple ways to clean water in the field:

* Filter out the particulates large enough to be caught in a fine screen.
* Purify with chemicals like chlorine (aka chlorination), iodine, or ozone to kill or deactivate bad stuff in the water. Just like a swimming pool.
* Use UV light to kill living organisms (similar to how medical equipment is sterilized).
* Boil water to kill living things.
* Distill water by boiling it and catching the evaporating steam, recollecting it into liquid water. This leaves anything that wasn’t pure H2O behind.

When looking at the kinds of products relevant to personal emergencies, it usually comes down to filters versus purifiers. The best answer is to have both. But if you only have one, a filter is usually the better choice.

Boiling takes time, fuel, and equipment. It’s a fine method, but it doesn’t make sense as a primary water plan in this context. Think of boiling as a backup or bonus.

> While we do recommend having some purification chemicals on hand as a backup, we don’t recommend them as your primary plan.
>
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For example, imagine you have filters in your bag that don’t protect against viruses. But the water around you seems sketchy or you know there’s an outbreak. You would filter the water to remove particulates, then boil it to kill anything left over.

Purifying chemicals seem attractive because they are relatively cheap, small, and lightweight. So they’re easy to buy and throw in a bug out bag pocket.

Besides wanting to avoid putting unnecessary chemicals in your body, chemical treatments take a long time — a normal-sized water bottle can take up to an hour or two to neutralize the hard-to-kill threats like cryptosporidium. Not only do they expire after a few years, but one water filter might clean up to 100,000 liters whereas a normal package of purification tablets might only clean 200 liters.

Chemicals, UV, and boiling will kill living contaminants but they don’t remove particulates and some chemicals. So you might end up drinking water that looks and tastes horrible even though it technically doesn’t have any living threats.

## How portable water filters work

Filters use physical mesh screens to block particles. How effective the filter is depends on how small the pore holes are, which determines what it blocks versus what it lets through.

Common sizes:

* Human hair: 50 microns wide
* Algae: 5-20 microns
* Protozoa: 1-50 microns
* Coal dust: 1-50 microns
* Asbestos: 0.7-90 microns
* Bacteria: 0.2-1.0 micron
* Radioactive fallout: 0.1-10 microns
* Virus: 0.004-0.3 micron
* Lead: 0.001-0.7 micron

*Note:* Some products play marketing games by saying they have a “nominal” size of X microns. This means it can block down to that size, but not always — so look for “absolute” ratings instead. The CDC found that some “nominal 1 micron filters” still let through up to 30% of 1 micron threats.

A virus can be 100 times smaller than bacteria, which is why any decent filter can screen out protozoa and bacteria, but only the tightest ones can filter viruses and other super-fine particles.

Some products mix technology, combining small filter pores with a kind of ionized coating around the mesh that attracts bad stuff as they float through. This is why some filters that are technically only 0.2 micron in size can still filter out 0.01 micron viruses.

Some filters also use activated carbon (e.g. activated charcoal) to attract and trap the smaller stuff that otherwise would slip through a mesh screen — similar to how activated carbon traps gases in prepper gas masks. Carbon will not only make the water taste and smell better, but it can remove some of the chemicals you’d rather not drink.

Fluoride, salt, and other elements are water soluble, which means they dissolve into the water and are no longer separate particulates that can be screened with a filter.

## Types of survival water filters

The difference comes down to how the water is forced through a filter. Water is either sucked through via your mouth, pulled through via gravity, or pushed through via a pump or squeezing motion.

* **Straw**: The simplest filters that move water through via suction from your mouth as you drink.
* **Bottle**: Essentially straws that are mounted inside of a bottle, so they filter as you drink.
* **Inline**: Versatile filters that have simple input and output attachment points, so you can use it as a straw directly in the water, screwed onto a bottle top, with a hydration bladder, or with a gravity bag.
* **Gravity**: Uses gravity to pull water through filter, typically with a bag of dirty water elevated above an inline filter with hose connections.
* **Pump**: Your hand movement forces water through.

One of our frustrations with this market is that most products are designed for a specific hiking, camping, or international travel need — not emergency preparedness. Which creates unfortunate tradeoffs and products that are never quite perfect. But newer filters (especially the inline models) are becoming more versatile, so you can use the filter in almost any possible configuration or scenario — something very important in prepping so that you can reduce weight and cost while increasing your ability to handle unpredictable scenarios.

### Top brands

* **Aquamira**: Known for their chemical purification methods, they also created some of the first versatile inline filters.
* **HydroBlu**: A relatively new Utah-based player to the market that surprised us with some quality product offerings.
* **Katadyn**: Based in Switzerland, this venerable company is known for their tough ceramic pump filters that last a long time.
* **LifeStraw**: They blew up and owned the survival straw category, becoming the name brand most laypeople have heard of. But their products are limited and often not the best choice.
* **MSR**: Great tech with unique products, but they tend to stay within their own product ecosystem. For example, their pump filters directly attach to their branded water bladders, but don’t come with hoses to easily pump into other third party products.
* **Platypus**: A great company with solid products (like water bladder bags), but they don’t seem to make their water filtration stuff in house.
* **Renovo**: A new company, their whole thing is a modular, versatile product family. They have three filters (MUV 1/2/3) that connect together, so you can use any combo you want based on the water quality. Those filters can attach to a mouthpiece to make it a straw, inside a bottle, or to a pump housing.
* **Sagan**: A relatively new brand in the space from the same California-based folks as Kelly Kettle, and they seem to be doing it right.
* **Sawyer**: When we poll preppers, the Sawyer is by far the most-often-recommended brand. We don’t always think they’re the best, but it’s a tried-and-true company with a reputation for filters that last a very long time.
* **Seychelle**. Well known in the water purification industry, but their personal products relevant for prepping seem to have fallen behind the curve.

There are brands you often see popping up around sites like Amazon that are actually white-labelled brands that take other people’s products (typically from unknown Chinese manufacturers like Diercon) and slap their name on top. An easy way to tell is if you can’t find a good website for the company.

We try to avoid these products. Common examples:

* Aquaway
* Etekcity
* JBW
* Life Defender
* Nature’s Hangout
* Outdoors 365
* Survival Hax

### How we review the best backpacking water filters

A good hiking or camping product might not be right for emergency preparedness. Context matters.

One example: The risk of contracting a virus from water in America is almost zero in normal life. So a recreational hiker measuring every ounce of carried weight doesn’t need to worry about having a filter that stops viruses. It would make sense for hikers to buy a cheaper filter that lasts longer and has a better flow rate (because of the larger filter pores).

Even if they did get sick, they’d have access to medical care. But both the risk and consequences are greater in some of the worst emergencies, so we consider viral protection more heavily.

We focus on product qualities that make sense for being away from home during a wide range of emergencies, such as:

* What kind of water and threats will it clean
* How portable is it
* Durability and shelf life
* Ease of use without instructions (the “10 year old child” test)
* Does it require batteries
* How much water can it clean without replacements or complicated maintenance
* How fast does it work

One of the trickiest parts is thinking about how you use various filters. Does it need a bag? Special hoses? Can you only use it in one situation? Will it work when you’re on foot in a suburb? In a desert?

For example, the most popular survival water filters (like the LifeStraw) have serious disadvantages because they only work when you are physically adjacent to a water source. You have to bend down and put the straw into the water, sucking in with your mouth.

We greatly prefer products that give us the option to put clean water into whatever vessel we want, for as much quantity as we want.

We generally don’t like “modular” products, like the Renovo MUV, because they typically have more moving pieces, higher risks of failure, can be confusing in the field, and require you to go all-in on their systems.

### About Survival Straws

* Avoid straw models. It’s very common that someone new to prepping buys a LifeStraw or something similar as one of their first purchases because they saw a blogspam review promoting it. But there are very few scenarios where we’d rather have a straw instead of the other types.
* Exceptions: They can be great for everyday carry uses. Or if you really want to have a straw, think of it as a nice-to-have bonus.
* The difference between a straw model and an inline model is that straws do not have the easy ability to attach standard hoses to the input and output ends, requiring you to dunk the input end in the water and/or use your mouth to bring water through.
* One of the main disadvantages is that you can’t filter water and then store it in a vessel. It only filters in the moment as you suck water through and into your mouth. Imagine if you wanted to cook or store it for later: Are you going to spit the water back into a pot or bag?
* Another major disadvantage is you have to get your face a few inches away from the water source. Sounds good in theory, but is more difficult in practice.
* Can be hard to suck the water through, especially as the filters get clogged up over time and flow rate drops.
* Pros: cheapest, smallest, lightest, simplest.

### About Filtered Water Bottles

* We recommend keeping drinkable water stored in your Bug-Out-Bag / Get-Home-Bag anyway — using a filtered bottle can be a good way to hit two birds with one stone, even if you keep the filter part detached during storage so it’s not sitting in water.
* We tend to dislike soft/collapsible vessels with internal filters. They can be great for lightweight hiking, but are not durable enough for emergency preparedness. Many products have consistent complaints of leaks in the vessel. If you’re going to go that route, you may as well get normal unfiltered soft pouches with 28 mm threads (like a Platypus bag) to use with your other, more versatile water filters.
* Bottle filters generally have a shorter life than other product classes, but are typically replaceable for $10-30. Some are backwashable.
* Better filters can be harder to suck water through because of the smaller pore sizes. Some bottles are soft or semi-squeezable so you can help push water through, while a few newer models (like the Lifesaver bottles) use extra pump/press mechanisms to assist.
* Don’t get tricked into buying a “filtered” water bottle that is more about turning tap water into “better” water with pseudoscience marketing for “wellness”, “ionization”, pH levels, fluoride, etc.

### About Filter Pumps

* Pumps are great because you do the work with your arms instead of your mouth.
* They usually come with input and output hoses. Some include a sanitation bag to keep your output hose clean during storage.
* Pumps work better than most other types in shallow water sources like puddles.
* You can create as much clean water as you want... just keep pumping.
* Many pumps use ceramic for their filters, a naturally porous material that traps particulates. Unlike membrane-based filters that use backflushing to clean out the trapped particles, ceramic filters are scrubbed down by hand with a brush or cloth. It’s easy to do and has some advantages, such as visibly seeing how much life the ceramic has left (instead of guessing on other types) and you don’t need a backflush syringe.
* Ceramic filters can’t block viruses.
* Pumps only work when you’re pumping them. You can’t daisy chain them with a bladder, bottle, or gravity bag the way you can with inline models.

### About Inline Water Filters

* If you’re only going to buy one filter, make it an inline model.
* The most versatile type — can be used on its own as a straw directly into a water source, screwed onto the mouth of a normal water bottle, attached to the hose of a hydration bladder, or even attached to the output hose of a larger vessel/bucket of water.
* The best models are surprisingly small and light, because they don’t have any pumps or other functions/attachments.
* Wide ranges of lifespan. Some models only last for 180 liters and some last up 378,000 liters. Don’t get caught up in the super-huge numbers though.
* All else being equal, a product that claims 300,000 liters isn’t inherently better than one claiming 200,000.
* No inline models filter viruses. Some unknown / Chinese manufacturers claim they do, but we’re skeptical.

### About Gravity Filter Kits

* Produces more water per minute than most other types and requires the least amount of physical effort because gravity does the work instead of your mouth or hand.
* Gravity kits are usually just a hangable bag and hose with an inline filter attached to the output hose. Some have the filter built inside the bag itself.
* Gravity bags are very popular and often the highest-rated portable filtration products in outdoor-focused publications or stores like REI.
* But that popularity is usually in a family camping context, because they filter water for large groups of people without much effort or moving around.
* We think there is prepping value in having the option to use gravity. It can make daily chores in a fixed position (like your home) much easier. But it’s a nice-to-have on top of a good foundation, not a need-to-have.
* We don’t like most of the off-the-shelf kits for one big reason or another.
* A DIY approach is probably better, where you pair an inline filter with any bag and hose. But our top choice gets you 95% of the way there. Assuming you have an inline filter anyway (like the Sawyer Mini), the extra weight/space of adding a gravity water bag and hose in your emergency kits is worth the benefit.
* Gravity bags are hard to use when water isn’t plentiful or deep, and you need elevated places to set the bag. They work well in wooded areas with lakes and rivers. But you shouldn’t assume that’s where you’ll be in an emergency.
* The models that use an inline filter on the output hose are easy to backflush. You just flip the filter around and let gravity push out the particulates.
* We don’t think you need two bags in a gravity kit. You always need a dirty bag. But the value of a special clean bag isn’t really applicable to prepping, except for the value of having a second bag to replace a torn dirty bag. If you need to fill something up, like a bottle or cooking pot, just take it to the dirty bag and let gravity fill your vessel. A separate clean bag doesn’t really improve that process except for saving small amounts of time.

## DIY Water Filters and Purifiers

https://preparednessadvice.com/an-inexpensive-water-filter-the-bucket-berkey/