What do ou use to treat 'iffy' water -- esp when camping/ hiking?
Filter, tabs, pen, other?

Katadyn Hiker,in the places i canoe around in you just need to filter the water,it does not need purification.anyplace else i would break out my yet unused Pocket Filter with the ceramic and silver element.

I prefer boiling. It gets every nasty thing, and I have used it successfully on some very questionable sources. My second choice is the K. Hiker, using a secondary filter to get the rocks out if there is a lot of sediment.

Katadyn Micropur MP1 tablets (chlorine dioxide). It's about all any of my hiking friends use too. Occasionally it's nice to use somebodies filter, but mostly not needed where we hike.

I hate to start with this answer, but it is so commonly true ----

It depends on the situation!

I have a type of most of the common tools, and use them all in different situations. Part of the situation is the threat of various organisms in a particular area. Where crypto is present, some of the chemical products (iodine and chlorine) don't work at all and the others are very slow. Where the viruses are present, most filters won't do the trick and need chemical treatment after filtering. Temperature is a problem for all of them except boiling, but different. For the chemical techniques, the time is lengthened considerably (which is already a problem with these techniques). For filters, damage to the filter from freezing has to be delt with. The SteriPen is battery operated and must be kept warm to work.

Katadyn Pocket Filter - great for a small group on the move where water is not universal (not under you - see SteriPen). My "universal" tool. It cleans most water (viruses are a problem, but not serious in most of North America). Sweetwater or other chlorine based chemicals will solve that problem. The water is ready to use immediately.

MicroPur Tablets - The tool for psk use, OK for short trips. Small, light and kills everything. Water not available for some time (up to 4 hours if crypto is a problem) so you have to carry several containers so that you have some available all the time.

SteriPen - Super for canoeing or other times where water is available all the time (especially if it is moderately clear). More of a problem (pre filtering) if the water is cloudy. Requires care to prevent cross contamination (especially if you use their immersion technique which is not a good idea imho). Batteries which some consider a problem and some do not. Water is available immediately. Slow if you need lots of water at one time.

MSR MIOX - Great for large groups (works well in bladders and other large containers) and stationary situations (I use mine a lot when working out of a base camp, fill a bladder in the morning and it is ready when I return - fill it in the evening and it is ready in the morning). Like the tablets, it is not the best for traveling because of the time potentially required. This requires lots of planning and containers (or multiple large containers).

Boiling - The most commonly used, why purify water if you are using it for tea or to reconstitute foods? Once it has boiled it is OK in most parts of the world. If you have an open fire it is a great technique for large volumes of water, but requires lots of capacity or stopping for fires during the day. Seldom do I use this by itself on a trip, but every trip I use it some.

I like and use all these tools. If I had to pick one it would be my Pocket Filter with the backup of SweetWater for areas with a virus problem.

Respectfully,

Jerry

OK Leading question - How do you know or suspect when crypto is present?

Add another voice to the Pur-Katadyn Hiker. I prefer getting the bits strained out of the water before I drink it. If just boiling or using a chemical purifier, sure that's fine to kill the bateria/virus but the added psychological benefit of having visually and tastefully clean water is worth every gram of weight to the people I hike with.

I've used the Hiker to clear water from heavy algaed coverd ponds, milky glacial melt water and running stream water. They've all benefited from the filter.

Chemicals are good in a pinch but the water as some extraneous taste. Even boiled water can taste funny after being used to clean cold water.

Although there have been reports in the Journal of the Wilderness Medical Society on sampling of several areas (mostly in the Sierra's) a map is my primary tool. I use the protocol described in the Field Guide to Wilderness Medicine by Auerbach, Donner and Weiss. The key is what is upstream of you. If there is agricultural land, built up areas (human habitation) or heavy use recreation areas - suspect contamination. The CDC reports about 300,000 cases of cryptosporides each year in the US. Most of them are associated with direct transfer but that tells me that if man is present crypto probably is too.

In high alpine areas I sometimes use water without treatment. If I do use treatment it is usually filtering. If there is some human presence (a common campsite in the wilderness) above me I use one of the above methods. If there is a very heavy use area (campsites on the AT, cattle or sheep grazing areas, a small town) I always use a technique (whatever one I might be carrying). More than that (Florida, 3rd world countries, etc.) I use a 2 step process (usually filtering followed by chlorine or UV).

Although treatment is, I think, a good idea, most wilderness infections come from poor sanitation - not properly washing hands, latrines too close to campsites (not necessarily your latrine), etc., not from contaminated water.

Respectfully,

Jerry