I’m off to Nepal to do some trekking soon and considering taking a water purifier with me mainly to ensure a safe supply of drinking water but also to do my bit at reducing the plastic bottle pollution epidemic. Can anyone recommend a good purifier that’s both compact and capable of producing enough clean water for two people for the duration of the Annapurna Circuit trek I’m reckoning on about a liter each a day for twenty one days. All I can say is, make sure you have some iodine tablets (and something to kill the taste) because you never know when the darn machine’s going to break.
I had a Pur Scout, which came highly recommended by the camping shop. By my third day in Africa it melted (and it was sitting in the same bag as my cheap camera, which was fine). It wasn’t unusable but it took three people to hold it together and pump at the same time. Yes, I would say that some kind of water purification equipment is quite esential. As many other people have said, your estimate of one liter per person per day indicates that you don’t have much experience with backpacking. If nothing else, buying 4 liters of bottled water per day per person adds up to a lot of money. It is also a lot of weight to carry.
When I travel in India, I use Polar Pure, a system based on iodine crystals (Kahn-Vischer method) with essentially unlimited capacity. Problems are that the bottle has to be protected against freezing, and any kind of chemical disinfection works poorly at low temperatures. Neither is a problem in lowland India, but 18,000 feet is a whole ‘nother question. I recommend asking advice or reading the FAQ in rec.backcountry. Generally, filters avoid problems with iodine flavor, potential toxicity, and temperature, but don’t filter out viruses, your most serious enemies. Also expensive, slow, sometimes heavy, and prone to breakdown. Iodine kills viruses very well, but is less effective against parasite cysts. Probably a combination of coarse filter and low-concentration iodine is best.
