
cascadedesigns.com/platypus, 10.75 ounces
Water filters are the bane of existence for our Southwest testers. Thanks to the region’s typically silt- and algae-prone desert waters, we’ve killed expensive filters in less than a gallon of use. And we’ve never found a very reliable filter. Until now.
Oh, the current Gravity Works system is still a filter, so we remain cynical, but these are the lightest, most convenient, and reliable water filters we’ve ever used. And that is something big. In our humble opinion, they’re as close to perfect as water filters get. With hoses, filter cartridge, zip case, and two four-liter water bags, the system weighs a mere 10.75 ounces and rolls into a 3 x 9.5-inch package. Using it couldn’t be simpler. One Platypus bag gathers dirty water, and another is for the filtered water. A long silicone hose and a low-pressure, two-micron filter cartridge quick-connect runs between the two bags. Fill the dirty water bag and hook up the system. Backflush briefly to speed up filtration by eliminating air bubbles in the filter, then hang the dirty water as high as possible (laying it on ledges also works). Come back in about five to ten minutes to find a gallon of clean, effortless water.
One 4.0-liter system easily kept five people chugging away during a three-day, 90-degree guided trek through Capitol Reef. Gathering water simply required scooping it, attaching hoses, and circling back periodically to check progress. Within an hour of hitting camp we had full hydration packs for next day’s hike, plenty of cooking and coffee water, and a spare bag filtering away overnight. Compared to the usual monotonous pumping and cleaning, this was a revelation. One tester claimed the gravity feed system regained him “one free hour every day.”
Despite back-flushing, the GravityWorks cartridge started to slow by the end of our 15-day trip. On the upside, full performance was easily restored by back-flushing several bags of hot sink water when we got back home. Two other identical cartridges did not show the same slowing during similar uses and time frames.
Despite these quibbles, this is still the most convenient, compact filtration system we’ve found. Light, easy to deploy, cleanable, and fast enough for on-the-move refills or group hydration. For January 2013 and beyond, GravityWorks has added 4.0-liter and 2.0-liter “Complete Kit” packages. These come with all accessories plus a Universal Bottle Adapter with waterproof connector that hooks directly to most reservoirs, bottles, or hydration tubes. So drink up, campers.
-Steve Howe





