The most important principle to staying alive in inclement conditions is keeping your core body temperature near 98.6F. It only takes 3 hours of exposure to extreme temperatures before really bad things happen to your body.
A close second is hydration. The body can react poorly in just 24 hours without water, and death likely after 72 to 100 hours without it. From the common emergencies (like municipal water contamination and freezing pipes) to the big disasters, almost every trouble scenario means you’ll need access to clean drinking water when the normal sources cease or can’t be trusted.
Of course the simplest thing is to start storing one gallon per day per person in sterilized PET plastic containers, or better yet, new containers meant for storing water. But water is so heavy, that storing beyond 2 to 4 week’s worth would require going to extremes, something the LDS Church reminds us over and over is not called for. That’s fine. Two to four weeks worth of water will see us through most emergency hiccups. But what if you never got around to storing water? What if you have to evacuate with little notice and forget or can’t bring the water with you? What if a really big earthquake or hurricane/flood disrupts everything for months? How would you provide clean water for your family then?
The answer is to own, and know how to use and care for, your own water treatment system.
Good water filters used to be pricey, bulky, required careful maintenance, and didn’t last very long before their expensive cartridges had to be replaced. Most did nothing for viral contaminants without the aid of harsh chemicals.
They are SO much better now.
All but a couple are inexpensive. Some last 4,000 to 16,000 gallons. Some last indefinitely. Others require no maintenance. Many are quite small, weighing only 3 oz or less. And several can now remove viruses mechanically. For a gearhead that appreciates a piece of great engineering, this is exciting stuff!
But sorting through all the options can lead to information overload and analysis paralysis. If you don’t have the time to do all the research yourself, in keeping with the spirit of this site, I’d like to shorten the learning curve and provide you with a list of recommended systems.
Before we proceed, according to the EPA, a water filter provides up to 4-log (99.99%) reduction of bacteria and protozoan cysts, like Cryptosporidium and Giardia (both far too common in North American water sources). This means no more than 1 part per ten thousand of the original contaminant remain. This is known as micro-filtration. To be considered a true purifier, the filter must provide 6-log (99.9999%) reduction of bacteria and cysts, and 4-log reduction in viruses, which are far smaller than bacteria. 6-log means only 1 part per million of the original contaminant remain. This is known as ultra-filtration. So a purifier is 100X better at filtration than a regular filter.
Still, a good water filter is sufficient for most in the US and Canada. The best filters are cleanable to lengthen the service life so that the cost per gallon is minuscule. If the filter can be flexibly used as a straw, spliced inline into a backpack hydration system, or attached to the bottom of a water bag or bucket, that’s icing on the cake. The finest micro-filters on the market today are those from Sawyer. You might purchase one Sawyer Mini ($20) for each person’s pack, or a Sawyer Squeeze ($35), 4-Liter Two Bag system ($140), or All-in-One ($50) to sustain the whole family.
But at 100X better filtration, as long as it doesn’t clog, stores indefinitely, and maintains decent flow, I’d much rather have the peace of mind of a true purifier. Currently in North America viral contamination in surface water is very rare. But I suspect that might not be the case in the future. When I began my search for the best purifier, I immediately bumped into some shady products. Unless the manufacturer can produce certified test results from an independent laboratory, it is best to pass on their product. Well, there are a number of “purifier” straws on the market, out of China, that look like they are different products from separate companies. But suspiciously they all share the same photocopied test result and parts explosion diagram. So I left these alone and continued the search. The result is the following spreadsheet if you are interested in the details of the hunt.
To summarize the matrix linked above, the finest purifiers on the market today are those made by RapidPure in Minnesota. Inexpensive. Long-lasting. No need to clean or backflush. Great flow rate. Many options and configurations. And the best, certified purifier-level virus removal figures (6-Log instead of the standard 4-Log). They can be purchased on Amazon, or from two local re-sellers, CampSaver and GetPreparedStuff. They offer straws for individual packs ($29), water bottles ($29), inline filters ($39 – $49), and base camp bag and bucket filters ($40 – $129). The next best options are the Sawyer Point Zero Two, in either the 4-Liter Two Bag System ($180) or base camp bucket adapter ($129) options. For some reason Sawyer does not offer their .02 purifier in either a straw or inline configuration, likely due to the pressure required to draw water through them. The next best is a toss-up between the LifeStraw Mission ($130) or the Berkey systems with black filters ($230 to $500).
Note that it doesn’t have to be a choice between filter or purifier. In fact, I think the best choice is both, first through a backflushable filter to handle the heavy lifting, then through a purifier just to be sure. This preserves the life of the purifier, most of which — except RapidPure — clog much quicker due to smaller pore size. It is a good idea to have at least one backup purifier as well, in case your primary means of treatment is lost, damaged or used up. Steripen, LifeStraw Family, Berkey and the new PURE Electrolytic Purifier are good choices.
If all this technology is not available or it fails you, it helps to know how to replicate how nature filters and purifies water. See and print off this DIY tutorial that only requires a large ceramic pot and bucket with a spigot. Or this popular 3-tier tripod or 3-tier bucket or solar still system repeated by many wilderness living and survival manuals. Or this solar disinfection option (aka SODIS), gaining popularity in 3rd world countries, using just glass or clear plastic containers and 6 to 12 hours in the sun.
May your water be clean, clear and tasty.