We’ve heard a lot of talk about the dangers of things like Cryptosporidium and Giardia, so I think we all agree on the need to purify our water. However, I don’t think we all agree on how to do that and that’s okay. There are several different ways to get the job done, but for me the most important things are ease of use, speed of purifying and durability. When I encountered sawyer’s products I got a bonus along with all those features: price. Sawyer has come out with some amazing inline filters that due to their design can take 99.9999% of those baddies out of your drinking water and do it while you drink through it. I’m talking about Sawyer’s 7/6/B Water filter and its relatives. They’re simple, inline, lifetime warrantied, back flushable water filters.

Most people consider there to be three methods for filtering water (unless you just strain it through your teeth). Some turn to chemical tablets (good, but only a few treat Cryptosporidium and they need anywhere from 30 minutes to 4 hours to do their job reliably). Others turn to boiling (a rolling boil will kill most of those nasties in your water). Then there are the filterers.

©Paul Osborn

To be honest I avoided portable water filters for years, and with good reason. The biggest factor was the amount of time and work needed to get the job done. After backpacking in a group and having people take turns getting their filter workout I was just about ready to take my chances drinking the water straight! I know that filtering is faster than chemical tablets and even boiling (taking into account cooling after the fact), but it also takes work. The last thing I want to do when taking a “break” on the trail is do more work. When it was my turn to pump I found that you couldn’t pump too quickly or the pump would slip and add to that the number of people who wanted water and your 15 minute break turns into 45 minutes! That was 10 years ago and now the options are pretty good and getting faster. There are even super compact filter units that will do a liter a minute. I still prefer the Sawyer 7/6/B water filter and here’s why.

First of all there is the filtration rating to consider. This little filter by Sawyer filters down to 0.1 microns. That’s 0.1 not one micron. That’s enough to get rid of bacteria, E. Coli, Giardia, Cryptosporidium and a little fungus called microsporidium (which gets as small as 1 micron). It means your water is super safe. How safe? That’s where the 7/6/b comes in. This little mathematic looking name stands for 7 log and 6 log. A log, besides being a fun place to sit on during a hike, is a term that in this context means that it removes 99.99999% of bacteria and 99.9999% (one less 9) removal of protozoa and Cysts. That’s more than most filters on the market and more than enough to keep your water clean in the Pacific Northwest. Oh and if you’re travelling abroad and are worried about viruses in your water supply, then never fear, Sawyer provides a Viral Water Purification version as well.

©Paul Osborn
©Paul Osborn

The second best part is the flow rate. You’d think that something that filters so finely would need more work or more time, but mine came in a 1 liter water bottle. It’s meant to be used in-line; you just suck the water through it! That should give you an idea of how quickly it flows. Its super quick After 2 months of regular use I can still gravity filter a liter in 1 minute and 20 seconds. That’s 1 minute and 20 seconds without any pumping. That means, if you wanted to gravity filter (they sell a separate setup for that too) you can just hang up the bag and filter for your friends without any sweating or hard work and actually relax during that break on the trail! (Their website and slogan is www.JUSTDRINK.net)

How do they get such good performance? They use a submicron hollow fibre membrane. Say what? It’s a concept they borrowed from technology used in medical dialysis. It uses a bunch of tiny tubes that give the filter a lot more surface area to filter through and thus a lot more speed. Just take a look at the image. These long tubes also mean a longer use time between cleaning.

How long of a life does it have? Well, they call it a Lifetime filter. They boast that you will never have to replace this, only back wash it. And, even though the rating is much finer, the submicron hollow fibre membrane lets them boast a 20:1 rating. That means that this filter does such a good job in comparison to other ceramic reusable filters that you’d have to backwash a ceramic filter 20 times before you’d have to backwash the Sawyer 7/6/B filter for the first time. Oh and the backwashing process is as simple as running clean water through the filter the opposite way you’ve been using it. Here’s a video of the backwashing process.

Sawyer has thought a lot about the backpacker/traveller’s needs. Even though my filter came in a 1 liter water bottle* (great for all the Nalgene users and coming it at only 7.5 oz armed with filter), it came with instructions on how to splice the filter into your hydration pack. (Check out a recent blog post of how I did it.)

Sawyer sells several different options and configurations. I bought my inline filter with water bottle for less than $30 at Walmart online. We use it even when drinking from questionable tap water. If you’re afraid of cutting apart your hydration pack hose and inserting it inline, they sell a 1 and 2 bag setup with hydration bags! If you want something even lighter, nose around their Sawyer’s website to come across their most recent addition, a super light squeeze filter which includes both water bags and a squeeze filter that comes in at only 3 oz. That’s great for ultralight backpackers and at $60 for the setup it can’t be beat.

Whatever your favourite form of water filtration is, you need to check Sawyer out. They have a wide variety of options and their hollow fiber membrane filters are hard to beat for convenience, quality, price and ease of use.

*The sawyer filter with water bottle is available online at walmart for only $30!

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