Figuring out how you're going to take questionably sanitary backcountry water from a stream, lake, or puddle that may or may not be entirely urine, and turn it into something you can drink is a problem that many people struggle with (and that many companies are vying to solve).
One of the more magical innovations in this field of water filtration/purification comes from SteriPEN – a company that manufactures water purifies that use UV light to turn non-potable water into something that won't give you the runs (or cholera – which also involves the runs).
Here's what the company has to say about their SteriPEN Ultra:
Overall I have mixed opinions on the SteriPEN, but to be honest, I really want to like it.
Here's the deal:
NOTE: There are five types of SteriPEN (at the time of writing this). This review focuses on the SteriPEN Ultra (the USB rechargeable one with an OLED screen).
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- Weight: 4.94 oz / 140 g
- Dimensions: 7.3×1.6×1.3 in / 18.5x4x3.3 cm
- Lamp Life: 8,000 treatments
- Battery: Internal Lithium-Ion (included with purchase) – USB Rechargable
- Battery Life: 100 .5 liter treatments or 50 1 liter treatments per charge
- Minimum Bottle Diameter:
FROM THE MANUFACTURER
- SteriPEN Ultra is proven to be safe and effective, eliminating over 99.9% of bacteria, viruses and protozoa that cause water-borne illness. Featuring a user-friendly OLED (Organic Light Emitting Diodes) display Ultra is rechargeable via a computer, outlet or portable solar panel. Ultra’s UV lamp treats up to 8,000 one-liter treatments.
WHAT WE LIKE
THE UV LIGHT | This may be the SteriPEN's biggest draw: that it uses UV light to treat water. Not only does UV kill bacteria and protozoa that can cause disease and digestive problems, but it rids your water of viruses too. Filtration is not an effective method of removing viruses from water, and if you don't want to have to add chemicals to or boil your water, then UV purification is an excellent option. As an added bonus you get to feel like a wizard whilst purifying.
THE SPEED | Although it may not seem like a big deal if you haven't yet experienced the joy of waiting for water to filter, the speed of the SteriPEN Ultra is a huge plus. The Ultra purifies .5 liter in 48 seconds and 1 liter in 90 seconds. It may seem trivial, but cleaning five liters of water (oh how I miss the desert), this can be a serious test of your patience. With UV, all the waiting is over.
THE PORTABILITY | Although the Ultra is not the smallest of the SteriPEN lineup (that honor goes to the SteriPEN Freedom), it is still incredibly portable. It will fit just about anywhere and you'll barely notice it in your pack (or pocket?). It's definitely a big step up from bulky gravity or pump filters.
THE EASE OF USE | This thing is ridiculously easy to use. Just fill up your container with water, select the amount you want to purify (.5 or 1 liter) and then insert the SteriPEN for 60-90 seconds. An added bonus of the SteriPEN is that it will not freeze like filtration systems that use ceramic filters (e.x. Sawyer products) so you don't need to worry about keeping it warm at night (although the bulb does require extra time to warm up in colder temperatures). You can also use it in whatever container you want (so long as you can get the light – and sensors – into the water).
WHAT'S JUST OKAY
THE WEIGHT | If you're not into ultralight, then you will have no gripes with the 4.94 oz / 140 g weight. However, if cutting every last bit of weight from your pack is what you're striving for, then there are other (lighter) options available to you (namely, the Sawyer MINI, iodine, Aquamira, bleach, or no filtration).
THE COMPATIBILITY | Although you should always be careful when dealing with water that might make you sick, you need to pay close attention with the SteriPEN. If you're filling water directly from a source you need to be sure to wipe down the threads and openings of your containers as the UV light will not reach them. Likewise, if you have an odd container with an awkward opening (e.x. a large water bladder) it is difficult to ensure a proper purification. Sometimes you really have no idea if you managed to blast all the water with the light and are really just crossing your fingers each time you take a drink. Solution? Make sure you've always got a compatible container.
THE CHARGING | Yes, the fact that the Ultra is USB rechargeable is awesome and futuristic and means no added weight from traditional batteries. However, this also means that if you don't get a chance to recharge (you need to filter more than 50 liters of water on a single charge), then your SteriPEN could end up being useless to you (unless you are carrying a solar charger / external battery). If you're not terribly concerned about saving weight (or just stoked on being able to recharge things), then perhaps the AA battery eating SteriPEN Classic would be a better choice.
WHAT WE NO LIKE
THE FLOATIES | If this wasn't obvious to you at first, then allow me to share it with you now: the use of a UV light instead of a traditional filter means that your water will still contain whatever was floating around in it when you scooped it up from the earth. SteriPEN does make a Pre-Filter to solve this problem that will attach to 32 oz / 0.94 l wide-mouth water bottles (at a cost of $13 and 1.5 oz / 43 g). You can always get around particularly bad water if you have the patience to wring water through a bandana (or whatever). However, if you're a champion and don't care about a bit of cowboy seasoning in your water (even if it is cow poop), then this might not bother you.
THE WATER OPTIONS | This fits in a bit with the point above, but since the SteriPEN uses light to purify water, if you come across a source that isn't transparent enough for light to penetrate, your SteriPEN isn't going to do you much help. Again, you can always wring the water through something to try to clean it up enough for use with the SteriPEN, but in some cases you may find yourself out of luck (and possibly ingesting disease-causing agents).
THE RELIABILITY | Here's where I really have reservations about the SteriPEN Ultra. In my experience, I have had two SteriPEN Ultras stop working on me. The first was dead out of the box after just one use, and the second died in the middle of the Sierra after two months of use. I didn't receive a standard error message either time, and the device simply just stopped working on both occasions. Since then, I have purchased a third (since I needed something for viruses in Nepal), and it has worked well – so far.
If you need a water purifier that's going to kill viruses (if you're hiking the PCT you don't need this) and putting chemicals in your water is not an option, then UV light (and maybe a SteriPEN) is what you need.
Although I've had difficulties with the reliability of the Ultra in the past, SteriPEN apparently offers a fantastic warranty on their products, and from what I've read they also have great customer service. Unfortunately, this won't help you if you're three days out in the backcountry and needing some clean water to drink (on the upside, your diseases incubation period is probably longer than three days).
It's always smart to carry a backup (or to bring along a friend to carry one for you).
Check out the SteriPEN Ultra here!