Preppers and survivalists have a ton of different options when it comes to water filters and purifiers. With all of the options available, it is good to know which water filter or purifier would be best for their specific application.
The Best Water Filters for Preppers and Survival are:
- Best Long-Term Grid-Down Water Filter: Berkey
- Best Water Filter for Wilderness Survival: Sawyer Squeeze/Sawyer Mini
- Best Water Filter for Urban Survival: Grayl Geopress
- Best Water Filter for Boil Water Notices: Sawyer TAP
In this article, I’ll cover why the filters listed above are the best options in specific situations, including what they remove as well as their lifespan. I’ll also discuss any basic maintenance that you need to perform to keep them running.
What’s the Difference Between a Water Filter and Water Purifier?
A water filter will remove sediment, bacteria, and protozoa. However, they usually don’t remove viruses or chemicals. Water purifiers, on the other hand, can remove sediment, bacteria, and protozoa along with viruses and chemicals.
A common example of a water filter is the Sawyer Mini or Sawyer Squeeze. Filters such as these rely on some sort of material to catch contaminants as water passes through them. The pores within the material are small enough that bacteria will get caught in them. Think of a fat kid trying to go through an inner tube. He just can’t squeeze through.
However, since viruses are smaller, they will likely just pass through the pores in the filtering material. Also, since this method of filtration is more “mechanical” it isn’t capable of absorbing chemicals.
A purifier, on the other hand, uses specialized media that binds pathogens and absorbs chemicals. This allows them to remove virtually all bacteria, protozoa, and viruses, as well as most chemical contaminants. However, because of this, they also tend to have a shorter lifespan than some filters. Some media types, most notably activated charcoal, will only last for so long after it is unsealed and can only absorb a certain amount of chemicals.
Best Long-Term Grid-Down Water Filter: Berkey
The best water filters for long-term grid-down situations are Berkey water filters. They are available in many sizes to suit the needs of different families and groups. The larger filters can hold more water as well as accommodate more filtering elements. This will allow them to filter water faster.
Individuals and couples would probably be fine with something small like the Travel Berkey. Families with 3 or 4 members would be better served with a Big Berkey, while larger families would need either the Imperial, Royal, or Crown Berkey. I have even seen a restaurant using a Crown Berkey to serve water to its guests. This would make it a good option for survival groups as well.
What makes the Berkey such a good choice for a long-term emergency is that it removes a ton of contaminants and it is easy to use. When you buy a Berkey purifier, they usually include a pair of “Black Berkey” filtering elements. These are made of a carbon composite that contains several different materials.
The elements themselves look like long skinny cylinders and Berkey claims they can remove bacteria, viruses, and a large portion of most common chemicals. Because of this, they are technically water purifiers, even though Berkey refers to their products as “filters”. Each Black Berkey element should last for 3,000 gallons, which usually means 2-5 years of use.
Related: Berkey Water Filter Review
A Good Everyday Filter
My favorite thing about Berkeys is that you can use them every day. The tap water in my city tastes absolutely horrible. Since Berkeys do such a good job removing chemicals they are able to completely eliminate the “chemical swamp water” taste of our municipal water supply. Since we use it every day, using it to purify water during an emergency will seem second nature since we use it anyway.
The main drawback to Berkey filters is their size. They are something that you’ll use at your home or bug-out location. You won’t be able to carry it around all over the place. The filtering elements themselves are also somewhat fragile, meaning you must be careful when transporting them.
Another concern that some people have regarding Berkeys is that they are not NSF certified. Berkey claims that their Black Berkey filtering elements have undergone testing from accredited laboratories. However, for this reason, I recommend a three-step water purification system for more long-term or serious emergencies. You can see how I would purify water for my family during such an emergency by watching the video below.
Sawyer Squeeze/Sawyer Mini
The best water filters for wilderness survival are the Sawyer Squeeze and the Sawyer Mini. I am lumping these together since they are basically the same filter, just in different sizes. The Sawyer Squeeze is slightly larger than the Mini, making it a little easier to use.
Sawyer filters use hollow fiber membrane technology to trap contaminants as they pass through the filter. They can filter down to 0.1 microns, which is small enough to remove sediment, bacteria, and protozoa from your water.
You can use Sawyer filters in a few different ways. The Sawyer Mini includes a straw that allows you to use it as a filtration straw to drink water directly from a natural source, such as a stream. You can also fill the included bag with water and connect it to the filter. The threads used to connect the filter to its bags are also the same as those found on soda bottles.
Sawyer filters have many qualities that make them ideal for wilderness or backcountry environments. First, they are capable of removing the types of contaminants that you could expect to have in remote water sources. Second, they are incredibly lightweight, making them excellent choices if you are needing to bug out or need water while hiking or camping.
Sawyer filters also have a long lifespan and are easy to maintain. You can use the included backflush syringe to force clean water through the filter to help remove any larger debris that has found its way into the filter. Sawyer claims that their filters can last for 100,000 gallons.
There are, however, a couple of drawbacks to Sawyer filters. The first is that they do not remove viruses or chemicals. The pores inside the hollow fiber membrane are too large to capture viruses. They also lack the ability to remove chemicals since they cannot absorb them.
Sawyer filters are also designed for individual use and have a relatively low filtering rate. They do make a gravity filter, which you can find here, which is essentially a Sawyer Mini that includes a large bag that can be hanged from a hook or tree limb. This would be a little more suitable for a small group but may still be slower than many people would like.
The Grayl Geopress is the best water filter for urban survival, and there are a couple of reasons why. The first one is that Grayl filters are water purifiers. This is important because you are more likely to encounter contaminants beyond just bacteria and protozoa in an urban environment. Being able to remove those along with viruses and some chemicals makes it a better choice than other filters, such as Sawyers.
Another reason why the Grayl Geopress is a great option for urban survival is that it is something that you can use on a daily basis. I use mine at work. Since it looks very similar to a sport bottle, it will blend in very well. If someone asks you about it, just tell them you don’t like the way tap water tastes and you wanted to save money at the vending machine. Using it daily will increase your chance of having it with you when you need it.
I have the Grayl Geopress, which you can find here. It has four main parts:
- Purifier Cartridge
- Inner Reservoir
- Outer Reservoir
The purifier cartridge attaches to the bottom of the inner reservoir and the cap screws onto the top of it. You then scoop water into the outer reservoir and press the inner reservoir into it. Water is forced through the cartridge as you continue to press down, removing contaminants in the process.
Since the cartridge is considered a purifier, the only real way to maintain it is to replace it. Each purifier cartridge has a lifespan of 65 gallons, which should be enough for 350 cycles. If unopened, they have a shelf-life of 10 years. You can find spare cartridges for the Geopress by clicking here.
Sawyer TAP Filter
The best water filter for boil water notices is the Sawyer TAP Filter. It has many of the features of other Sawyer filters but is specifically designed to fit on a faucet. The Sawyer TAP can also be attached to outdoor spigots when used with its included spigot adapter.
This is possible because the TAP filter has a rubber gasket on the bottom of it that slides over and seals against a faucet. Other Sawyer filters have threads that are used to attach them to water bags or different types of bottles.
Like the Sawyer Mini or Squeeze, the TAP Filter can remove contaminants as small as 0.1 microns. This is small enough to take care of bacteria, protozoa, sediment, and microplastics.
That level of filtration should be appropriate for many situations that result in boil water notices. The main exception would be when sewage backs up or overflows over a large area. This would most likely happen during a flood or hurricane.
In a situation such as that, viruses may find their way into water lines or other portions of the system. Since the Sawyer TAP cannot remove viruses, you would still want to boil the water or use bleach to disinfect it. However, it would likely be okay to just use the TAP filter in situations where a boil water notice is in effect simply because of a loss of pressure.
Maintaining the TAP Filter is very similar to how you would maintain other Sawyer filters. You can backflush it using the included accessories.