Jake Larsen
WKR
I've been dreaming about the perfect backcountry gravity style filter for a long time. Imagine rolling into your campsite after hiking in, dipping a bag into the water source near camp, and by the time your shelter is set up, you've got 6-12L of clean water waiting for you. I figure it could save between 1/2 hour and 45 minutes a day (depending on what pump filter you normally use), and a big hassle. Less time spent in camp means more time on the mountain hunting.
I've tried a couple systems over the last few years without much success. I found most of the filters to be cheap, resulting in very unreliable flow rates over the course of any extended trip. Long story short, not one of them have I ever trusted enough to rely on for an extended backcountry hunting scenario.
I was in the process of testing my own pieced together system last year, when I heard about a new startup company called Airborne Outfitters. This is a passion project by Jason Evatt, Lt Col. USAF. Now in retirement, his company is dedicated to putting the best gear in the packs of our Boys overseas, and it just so happens that there's a lot of crossover use for the backcountry hunter. Enter the Bitterroot Bag.
The Bitterroot accomplishes everything I was hoping for a Bag filter and more. Keep in mind, this was designed primarily for the military. I am going to suggest a few modifications to the system to make it perfect for my needs as a backcountry hunter, but its highly adaptable to different scenarios. These were my considerations:
1) The filter has to be high quality, with a good flow rate and an easily replaced filter cartridge.
The Bitterroot comes with the Aquamira Frontier Max. This is the perfect inline filter for the job. It integrates with the Aquamira "Universal Quick Connect" (UQC) system, which makes it perfect for customization. Airborne Outfitters sends the unit with the "red line" series filter installed. I recommend purchasing a couple of the "green line" series filters instead. The red line filters make perfect sense for the Boys overseas, where they might be encountering all sorts of nasty viruses ect. The green line filters are plenty safe for backcountry use in the US, and will provide a significant flow rate increase. I also carry one replacement cartridge with me when I'm relying on the Bitterroot as my primary water treatment. The cartridges re less Than 1 oz. These are available on Amazon.
The Bitterroot has a priming bulb above the filter, which solves the flow rate problems I've encountered in other systems. This allows you to prime the water lines, creating the proper vacuum to pull water through the filter. Last season, I filtered about 130L of water through one "green line" filter over the course of several backcountry fishing and hunting trips before the flow rate was slow enough that I needed to swap filters.
2) Must integrate with sensible camp water storage solutions.
I've always preferred to use the MSR dromedary bags for camp water storage. They come in 2L, 4L, 6L, and 10L options. I usually carry a 6L or 10L bag for camp water, and they've never let me down. In order to get the most out of a bag filter, I wanted to be able to direct connect the clean water hose from the hanging filter to my MSR bags. This way, I don't have to babysit the water filtering process. I can dip the dirty water bag, hang it, connect it to my big MSR dromedary, and walk away. This is where the Aquamira UQC system comes in really handy. I purchased an extra male/male UCQ adapter, which plugs directly into the clean water side of the Frontier. To this, I connected about 3 feet of the clear tubing. Now I just needed to connect that hose to my MSR bag. I needed a cap with the correct thread pitch to fit onto my dromedary, but with an open exit port sized for standard tubing. I tried to do this several ways, but ended up purchasing a "hydration kit" from MSR, designed to convert the dromedary bags into a camelback type system. I cut away the bite valve and tubing, and connected the cap to the male/male UQC adapter via the 3 feet of tube. With a little ingenuity, I'm sure you could rig something very similar to this with any other brand of water storage bag.
One full dip with the Bitterroot fills a 10L dromedary with extra to spare. Two 6L Dromedary bags are ideal.
The Bitterroot comes standard with a long section of hose between the priming bulb and the bag itself. This is so it can be used as an on demand system, much like a camelback. For example, a person could dip dirty water, roll and secure the top of the bag, connect up the filter lines, and put the bag of dirty water directly into their pack. The tubing would feed through the hydration port on the pack, and the filter would sit in-line with the system. Then, you could use a UQC adapter to connect a bite valve to the Frontier. I don't ever use the bag in this way, so I made a modification to this part of the system. I cut the rubber tubing to about 8 inches between the bag and the priming bulb. This creates the right overall length so when I hang the bag at head height, the MSR dromedary lays on the ground directly below the bag. Its much more manageable this way, cuts some extra weight I don't need, and I think it promotes good water flow.
I also added an alligator clip to the section of hose above the priming bulb. This allows me to shut off the water flow when my dromedary bag is full of clean water, but the Bitterroot still has water in it. I can swap to another empty dromedary, or just leave the extra water in the Bitterroot for later filtration without spilling water everywhere. Unfortunately I haven't been able to find anywhere to purchase these. I got mine from an old Katydyn bag filter I had laying around.
3) The whole system needs to be lightweight and durable.
I cannot speak enough about the durability of this bag. I abused mine over and over and it's as good as new. One of our elk camps this year was high on a ridge. We were dropping 500ft to a flowing seep, dipping the Bitterroot in the stream, rolling and fastened the top of the bag and carrying it 3/4 mile back to camp. It was slung over the shoulder, set on the ground, ect ect. I have complete confidence that its not going to fail.
I stuffed all the parts into an old Katydyn filter bag I had laying around.
After modifications, the whole system weighs in at 13oz on my scale. Not bad!
The Bitterroot has also been designed to fill other roles. It can be used as a dry bag during a pack-In for extra protection of down sleeping bags/jackets. It also comes with a specialized piece of tubing designed for blowing up sleeping pads. I tried this out, and it works great. Some people get very light headed when blowing up sleeping pads/pillows at high elevation, and this could be a real help if that bothers you. For the extra 1.5oz, I'm probably going to leave it at home.
There are limitations to this system. I would only bring this as my primary water treatment if I am going to a place I KNOW for sure has a clear flowing water source. Some of my hunting areas do not fit the bill. Sometimes water sources are seeps that must be dug out and carefully filtered with a pump or straw style filter. This system is obviously not suited for such places. I'm often hunting with a partner, so one of us can carry a reliable pump style filter such as the Katydyn Hiker Pro, while the other packs in the Bitterroot to handle camp water. This way we get the best of both worlds and cover our bases.
The Frontier max normally comes with a bite valve attachment, which allows it to be used as a "straw" Unfortunately Airborne Outfitters doesn't include that attachment with the Bitterroot right now. I purchased a Frontier in 2019 when I was putting together my own gravity system, so I have one laying around. It's worth noting that you can pull the Frontier out of the Bitterroot, add the bite valve and throw it in your pack. If i am using the Bitterroot solo and as my primary water treatment, I'll usually do this if I'm leaving camp for a long day loop.
I've reached out to Jason about all the modifications I made to the system. He was very receptive to the feedback, and Airborne Outfitters is now in the process of configuring a version of the Bitterroot specifically for backcountry hunting. Keep that in mind if you're thinking about purchasing.
I think the Bitterroot is best suited to base camp type scenarios, when you're coming back to the same camp for days at a time. In these situations, it's going to save you tons of time and effort. With a little imagination, it can be customized to fit your style and needs. Made in the USA by a veteran owned company is icing on the cake! Bitterroot bags are available at Airborneoutfitters.com
Priming bulb unit after modifications. Cut hose back to 8" and added alligator clip
Connection from the Frontier to a MSR Dromedary, via UQC + hose
Bitterroot system after modifications, with a 6L MSR Dromedary. I have it hanging at head height by a small loop of 550 cord
Everything tucks into a Katydyn bag
13 oz!
This is the piece designed for blowing up a sleeping pad, using the bag like a bellows.
Frontier with bite valve for use like a LifeStraw
I've tried a couple systems over the last few years without much success. I found most of the filters to be cheap, resulting in very unreliable flow rates over the course of any extended trip. Long story short, not one of them have I ever trusted enough to rely on for an extended backcountry hunting scenario.
I was in the process of testing my own pieced together system last year, when I heard about a new startup company called Airborne Outfitters. This is a passion project by Jason Evatt, Lt Col. USAF. Now in retirement, his company is dedicated to putting the best gear in the packs of our Boys overseas, and it just so happens that there's a lot of crossover use for the backcountry hunter. Enter the Bitterroot Bag.
The Bitterroot accomplishes everything I was hoping for a Bag filter and more. Keep in mind, this was designed primarily for the military. I am going to suggest a few modifications to the system to make it perfect for my needs as a backcountry hunter, but its highly adaptable to different scenarios. These were my considerations:
1) The filter has to be high quality, with a good flow rate and an easily replaced filter cartridge.
The Bitterroot comes with the Aquamira Frontier Max. This is the perfect inline filter for the job. It integrates with the Aquamira "Universal Quick Connect" (UQC) system, which makes it perfect for customization. Airborne Outfitters sends the unit with the "red line" series filter installed. I recommend purchasing a couple of the "green line" series filters instead. The red line filters make perfect sense for the Boys overseas, where they might be encountering all sorts of nasty viruses ect. The green line filters are plenty safe for backcountry use in the US, and will provide a significant flow rate increase. I also carry one replacement cartridge with me when I'm relying on the Bitterroot as my primary water treatment. The cartridges re less Than 1 oz. These are available on Amazon.
The Bitterroot has a priming bulb above the filter, which solves the flow rate problems I've encountered in other systems. This allows you to prime the water lines, creating the proper vacuum to pull water through the filter. Last season, I filtered about 130L of water through one "green line" filter over the course of several backcountry fishing and hunting trips before the flow rate was slow enough that I needed to swap filters.
2) Must integrate with sensible camp water storage solutions.
I've always preferred to use the MSR dromedary bags for camp water storage. They come in 2L, 4L, 6L, and 10L options. I usually carry a 6L or 10L bag for camp water, and they've never let me down. In order to get the most out of a bag filter, I wanted to be able to direct connect the clean water hose from the hanging filter to my MSR bags. This way, I don't have to babysit the water filtering process. I can dip the dirty water bag, hang it, connect it to my big MSR dromedary, and walk away. This is where the Aquamira UQC system comes in really handy. I purchased an extra male/male UCQ adapter, which plugs directly into the clean water side of the Frontier. To this, I connected about 3 feet of the clear tubing. Now I just needed to connect that hose to my MSR bag. I needed a cap with the correct thread pitch to fit onto my dromedary, but with an open exit port sized for standard tubing. I tried to do this several ways, but ended up purchasing a "hydration kit" from MSR, designed to convert the dromedary bags into a camelback type system. I cut away the bite valve and tubing, and connected the cap to the male/male UQC adapter via the 3 feet of tube. With a little ingenuity, I'm sure you could rig something very similar to this with any other brand of water storage bag.
One full dip with the Bitterroot fills a 10L dromedary with extra to spare. Two 6L Dromedary bags are ideal.
The Bitterroot comes standard with a long section of hose between the priming bulb and the bag itself. This is so it can be used as an on demand system, much like a camelback. For example, a person could dip dirty water, roll and secure the top of the bag, connect up the filter lines, and put the bag of dirty water directly into their pack. The tubing would feed through the hydration port on the pack, and the filter would sit in-line with the system. Then, you could use a UQC adapter to connect a bite valve to the Frontier. I don't ever use the bag in this way, so I made a modification to this part of the system. I cut the rubber tubing to about 8 inches between the bag and the priming bulb. This creates the right overall length so when I hang the bag at head height, the MSR dromedary lays on the ground directly below the bag. Its much more manageable this way, cuts some extra weight I don't need, and I think it promotes good water flow.
I also added an alligator clip to the section of hose above the priming bulb. This allows me to shut off the water flow when my dromedary bag is full of clean water, but the Bitterroot still has water in it. I can swap to another empty dromedary, or just leave the extra water in the Bitterroot for later filtration without spilling water everywhere. Unfortunately I haven't been able to find anywhere to purchase these. I got mine from an old Katydyn bag filter I had laying around.
3) The whole system needs to be lightweight and durable.
I cannot speak enough about the durability of this bag. I abused mine over and over and it's as good as new. One of our elk camps this year was high on a ridge. We were dropping 500ft to a flowing seep, dipping the Bitterroot in the stream, rolling and fastened the top of the bag and carrying it 3/4 mile back to camp. It was slung over the shoulder, set on the ground, ect ect. I have complete confidence that its not going to fail.
I stuffed all the parts into an old Katydyn filter bag I had laying around.
After modifications, the whole system weighs in at 13oz on my scale. Not bad!
The Bitterroot has also been designed to fill other roles. It can be used as a dry bag during a pack-In for extra protection of down sleeping bags/jackets. It also comes with a specialized piece of tubing designed for blowing up sleeping pads. I tried this out, and it works great. Some people get very light headed when blowing up sleeping pads/pillows at high elevation, and this could be a real help if that bothers you. For the extra 1.5oz, I'm probably going to leave it at home.
There are limitations to this system. I would only bring this as my primary water treatment if I am going to a place I KNOW for sure has a clear flowing water source. Some of my hunting areas do not fit the bill. Sometimes water sources are seeps that must be dug out and carefully filtered with a pump or straw style filter. This system is obviously not suited for such places. I'm often hunting with a partner, so one of us can carry a reliable pump style filter such as the Katydyn Hiker Pro, while the other packs in the Bitterroot to handle camp water. This way we get the best of both worlds and cover our bases.
The Frontier max normally comes with a bite valve attachment, which allows it to be used as a "straw" Unfortunately Airborne Outfitters doesn't include that attachment with the Bitterroot right now. I purchased a Frontier in 2019 when I was putting together my own gravity system, so I have one laying around. It's worth noting that you can pull the Frontier out of the Bitterroot, add the bite valve and throw it in your pack. If i am using the Bitterroot solo and as my primary water treatment, I'll usually do this if I'm leaving camp for a long day loop.
I've reached out to Jason about all the modifications I made to the system. He was very receptive to the feedback, and Airborne Outfitters is now in the process of configuring a version of the Bitterroot specifically for backcountry hunting. Keep that in mind if you're thinking about purchasing.
I think the Bitterroot is best suited to base camp type scenarios, when you're coming back to the same camp for days at a time. In these situations, it's going to save you tons of time and effort. With a little imagination, it can be customized to fit your style and needs. Made in the USA by a veteran owned company is icing on the cake! Bitterroot bags are available at Airborneoutfitters.com
Priming bulb unit after modifications. Cut hose back to 8" and added alligator clip
Connection from the Frontier to a MSR Dromedary, via UQC + hose
Bitterroot system after modifications, with a 6L MSR Dromedary. I have it hanging at head height by a small loop of 550 cord
Everything tucks into a Katydyn bag
13 oz!
This is the piece designed for blowing up a sleeping pad, using the bag like a bellows.
Frontier with bite valve for use like a LifeStraw
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