You should plan on purifying your water in almost all locales. You can buy water purification tablets but they can also disrupt the natural bacteria in your digestive system. You can also now get mini-UV sterlizers called SteriPens http://www.steripen.com
I've used them camping and trekking in Southeast Asia, the Pacific Islands and the mainland USA and am happy with them. about 6 years ago
I always take puritabs, but have never used them. I get the lodge to boil water each evening for me which they put into my Sigg bottle - it acts as a hot water bottle in my sleeping bag as well, then is cool enough to drink the next day.
I have heard of the "steripens", but have never used them.
Regarding water, do not even use the unsterilised water to brush your teeth, unless you want to risk visiting the toilet regularly for a few days! about 6 years ago
There is also the option of these:
15nm filter bottles that filter out all bacteria and viruses. Bit expensive but you could also take 4 replacement filters and give the bottle away to a school or something there :)
Ordering from the UK might also be an option because the cost in Aus is about $100 above the converted amount. about 6 years ago
I definitely recommend the Steripen. It may seem expensive, but you would end up spending much more on bottled water over the course of a trip... plus you're not throwing away lots of plastic bottles... also though, during trekking season on the more popular treks they have set up water-refill stations that have purified water. about 6 years agoAnswered by J via WorldNomads.com
I recommend bring purification tablets, which you can buy locally in Kathmandu before your trek. Even if you end up mostly drinking boiled water (we did - hot water bottle by night, drinking water by morning) they are handy and quick and easy to use. Check out KEEP in Katmandu before you go and grab reliable supplies and advise. Don't drink any water in Nepal without treating it first. Seriously. And bring some antibiotics with you trekking - ask a pharmacist in Kathmandu what you need for stomach bugs and buy it (it's over the counter and dirt cheap). Just in case. about 6 years ago
I trekked to Everest Base Camp last year - do yourself a favour and buy yourself a Steripen. At first it seems like a massive outlay, but totally worth it. Make sure you take 1 -2 metal bottles and not plastic. about 6 years agoAnswered by Jane via WorldNomads.com
Why do you want to take metal bottles versus plastic? over 5 years agoAnswered by Claudia via Travellr.com