Survival Water - Sawyer 4 Way Filtration System
Filtering water in some short term survival situations might be easily handled with a $20 survival straw and they certainly have a place in emergency preparedness; however, their ability to filter large amounts of clean water especially for cooking, cleaning, and non immediate use is limited. A Sawyer water bottle with filter kit caught my eye as being well suited for a wide variety of emergencies; especially should the situation last longer than a couple days.
Sawyer 4 Way Filter Kit
The Sawyer 4 Way kit (Model #149) includes a large blue 34oz water bottle which features a flip top lid and includes three separate drinking straws. Removing the cap reveals a hose attached to the under side which runs down to the filter itself; the hose keeps the filter just off the bottom of the bottle allowing water inside the bottle to be drawn up through the filter. Also included in this kit is a faucet adapter for home use filtering or it can be used to back flush the filter. Finally, included in the box were a couple of zip ties, a tube re-connector, tube adapter, instructions and warranty documentation.
Using the filter and water bottle combination is about as simple as you can make water filtration; you simply fill the bottle with unclean water reattach the lid with filter attached and suck clean water up through the straw. Sucking water through the straw does require noticeably more effort then drinking through a normal straw as the water is being pulled through the filter. However, you can get a good stream of water moving through the filter without much difficulty and you quickly get used to the extra amount of suction required to get water. The included blue bottle has a listed 34oz capacity but be sure not to fill it completely full as the filter will displace some water when the lid is placed back on.
Another popular way to use the Sawyer 4 Way is as an inline water filter on the hose of a hydration pack; this allows you do fill the hydration pack with questionable water and then use as normal receiving clean water by the time it reaches your mouth. To test this I used a cheap 3 liter hydration pack; I cut the hose so the filter would rest toward the top of the pack near the lid if it were inserted in a backpack hydration pouch. I simply cut the hose and pushed the hose back together on either side of the filter with the large end of the filter nearest inline toward my mouth. This worked great and I had no problem with leaking but the instructions suggest using the zip ties on both ends of the filter presumably to keep them from separating if there was tension on the hose. After the filter is removed the hoses can be reattached with the included re-connector just be sure to clean the hydration pack thoroughly.
One of the main reasons this Sawyer kit caught my attention was its ability to be used in a gravity system; this allows large amounts of water to be filtered for cooking, cleaning, or storage with little effort. You can use the hydration pack in a gravity system which is one of the reasons I went with the large 3 liter hydration packs; just hang the bag higher than the filter and let water flow though the filter into a clean container. You can leave the tube and mouth piece attached and this will allow you to shut off the water flow when a container is full; I removed the hose with mouth piece so I could get the process in frame for the camera and it worked good that way as well. In the future I would like to connect this filter in a bucket system which would allow for even larger quantities of water to be filtered with very little hassle.
If you have water pressure and would like to run water through the Sawyer you can use the water filter faucet adapter and filter water directly from the tap. This is done by placing the white rubber end of the adapter around a faucet and plugging the small end of the filter into the clear hose at the other end of the adapter. The word flow is written on the filter in large letters with an arrow pointing in the direction the clean water should go. Conversely, this faucet adapter is also how you back flush the system, to do this simply remove the filter and rotate it so the large end of the filter attaches to the clear plastic hose going against the flow arrow. Be sure that when you are back flushing that you are using clean water; for example, you probably shouldn’t be filtering and back flushing from the same faucet. Like all faucet adapters it depends on the shape of your faucet on how tight a fit you will get, and my faucet did have some leaking around the adapter.
I feel that the Sawyer 4 Way filter kit has a lot going for it. First it is affordable at about $55 dollars at the time of this writing; while I wouldn’t exactly call that cheap, when compared to most of its competition it is definitely one of the more affordable options. Second, it is very simple, dirty water enters one side of the filter and clean water comes out the other side; there are no moving parts to break and no elaborate connections to leak. Third, the filter is very lightweight weighing in at just 2.3oz, and the entire bottle with filter weighs only a bit over 6oz empty. Fourth, the level of protection on this filter is .1 micron, which is better than the .2 or .3 micron found on most of its competitors current models. Next, you don’t need to replace the filter, the unit is rated for 1 million gallons; while I’m not sure if it will do that much or not, the important part is it can be simply back flushed with clean water to keep in running essentially indefinitely. Finally and maybe most impressively is the versatility of this unit; this filter can be used in numerous setups including water bottles, hydration packs, gravity systems, or even under pressure from a faucet.
While I do feel the good aspects of this filter definitely outweigh the bad there are a few things that I didn’t like about this particular filtration kit. First, I thought that the included blue water bottle was a bit on the cheap side, it just didn’t have the rugged or quality feel of a Nalgene or Camelback style bottle. Next, this particular kit Model #149 did not come with a syringe which could be used for back flushing in the field or when there is no water pressure to use the faucet adapter. Finally, because of its design the Sawyer doesn’t filter chemicals; however, about the only portable water filtration systems that do are the pump kind which have moving parts, several different hoses and connections, are heavier, and generally more expensive. That said if filtering chemicals is one of your biggest concerns the pump style would probably be the way to go. I personally just pack a survival straw capable of removing chemicals should I doubt the water source I’m drinking from might contain chemicals.
As I mentioned I wasn’t too excited about the blue water bottle that came with the kit; the good news is that the cap will fit on a large mouth Nalgene bottle, so I ordered a clear 32oz Nalgene bottle. The cap fit perfectly on the Nalgene bottle and the only modification I had to make was to cut about a half an inch off the hose going down to the filter because the original blue Sawyer bottle was a little taller. The clear Nalgene bottle also allows me a good view of the water I’m about to filter and in many cases might lead me to dump the water and try for a better fill to save on plugging the filter. Which brings me to the other addition I made to the kit, I decided to purchase a syringe so I could back wash the unit in the field or without the aid of the faucet adapter which requires water pressure. I placed one of the spare drinking tubes on the large end of the filter and filled the 60ml syringe with clean water and placed it tightly into the open end of the drinking straw and forced the water back through the filter against the direction of the flow arrow.
Summary & Update
I currently carry my Nalgene/Sawyer combo empty of water with the filter, syringe, re-connector, and spare drinking straws inside the Nalgene bottle all of which is nested inside a metal GSI cup and this has served me well. However, since assembling my setup Sawyer has introduced a new filter called the Mini which filters to the same level of protection as the version in this review, the Mini is also capable of being used on disposable water bottles, hydration packs, or used like a survival straw. Furthermore, it comes with a syringe for backflushing and sells for about $20, so I would recommend checking it out. If you wanted to build a Nalgene based bottle like the one I put together I would look at the Sawyer Sport Bottle ($29) which includes a syringe for backflushing but lacks the faucet adapter and hose splices but retains the other capabilities of the filter in this review. Finally, for those looking to put together a 5 gallon bucket system Sawyer offers a Bucket Kit ($120) that can be used with your 5 gallon buckets to create a large gravity based filtration system that is still durable and easily transportable.