The Platypus GravityWorks 4 Liter System is a great way to keep a bigger group supplied with water. Clean, safe water to drink is one of those things we must always have. Backpacking made me appreciate modern comforts of living in a house, air conditioning, a soft bed and more. Safe water to drink is on this list too. I haven’t had any trouble with drinking unsafe water outdoors, and I plan to keep it that way.
You have quite a few options when it comes to water filtration in the backcountry. There is the good old-fashioned boiling method, chemical tablets, or filters. You can pump or squeeze water through a filter, but the Platypus GravityWorks uses an easier method. I bet you guessed that gravity does all the work with the GravityWorks filter. All you need to do is fill the dirty reservoir, connect the hoses and place the clean bag below. The water runs through the hollow fiber filter as easy as falling off a log while you sit back and watch or take care of other chores.
The Platypus GravityWorks filters water quickly even though no work is needed. In my testing, the filter took care of a full 4-liter dirty bag in just about 3 ½ minutes. Platypus says the GravityWorks will filter up to 1.75 liters per minute and that is about a minute faster. Since gravity is handling the chores, putting the dirty reservoir as high as possible makes for faster filtering. I used whatever tree limbs were around to hang the dirty side, so my filter times are a bit longer.
As the filter cartridge gets dirty, filtering will slow down, and when that happens, just clean the filter cartridge. You can do this in the field and all you need to do is run water backward through the cartridge to backwash. Just lift the clean side above the dirty and let water flow that way for a few seconds. Do this a few times and you are back in business. Check out this YouTube video from Platypus for some great information on backflushing and checking your filter for damage.
The GravityWorks filter system will keep nasties out of your drinking water. This line is straight from the Platypus website. “Every microfilter is individually tested to ensure it meets all EPA & NSF guidelines for the removal of 99.9999% of bacteria and 99.9% of protozoa*.” Just be sure to keep the dirty side stuff away from the clean side to avoid cross-contamination. You can also add the Platypus carbon filter element to improve smell and taste and remove some organic compounds. Platypus says the GravityWorks has a lifespan of 1,500 liters.
The Platypus GravityWorks 4 Liter System weighs 11.5 ounces, so I don’t think you’d carry it on a solo backpacking trip. Platypus makes other versions of the system that are much lighter if they better suit your needs. When I squeezed everything into the included stuff sack, the test filter measured about 5 ½ by 2 by 10 inches, so pretty small. Webbing straps with buckles are fastened to both reservoirs for hanging so you don’t have to have rope with you.
The Platypus GravityWorks 4 Liter system works great for large groups. I went on a camping trip to the lake with more than a dozen friends and we all used one GravityWorks filter. We just hung the dirty reservoir at the campsite and filtered straight to our bottles. When the water ran out, someone just ran the dirty bag down to the lake for a refill. If you aren’t near the water source, you can still carry 8 liters of water back to camp. Filter 4 liters of water and then re-fill the dirty reservoir for filtering later.
Platypus made the GravityWorks system really easy to use. A heavy-duty Ziploc-type closure at the top of the dirty reservoir holds well. I held this bag upside down and shook as hard as I could. The closure didn’t fail, and no water came out. The design of the dirty reservoir means that you’ll have to be able to scoop water in through the top. This is no problem at all if the water is deep enough. If not, use a scoop to collect water and pour it in. Water does not flow from the dirty reservoir until a hose is clicked in the bottom.
An included hose clamp stops water flow well if you need to pause filtering for any reason, and a screw-on cap for the clean reservoir keeps water in there. Setup of the filter is fast and easy, and the included stuff sack easily holds all the parts. Like I said before, there’s no work at all to doing the filtering. Gravity takes care of that for you.
The Platypus GravityWorks 4 Liter system has an MSRP of $109.95. The filter is easy to set up, use, and store and it works great for large groups. Check out the Platypus website by clicking HERE.
Thanks to Platypus for sending out the GravityWorks filter for test and review.