Making Safe Drinking Water (on the trail)

[RoySwkr]

I used boiled water and then iodined it in Nepal; and still got sick. Guess it wasn't boiled long enough....

Water boils at lower temperature at higher elevations hence must be boiled longer, perhaps DP will provide the formula. And it takes iodine a while to work. Fortunately BE isn't dealing with 3rd world countries where poor public health leads to a lot more human pathogens floating around.

 

[DougPaul]

I used boiled water and then iodined it in Nepal; and still got sick. Guess it wasn't boiled long enough....

Don't forget that you can also get sick from contaminated food or hands.

Water boils at lower temperature at higher elevations hence must be boiled longer, perhaps DP will provide the formula.

Tables of [average] boiling point vs altitude are available from many sources (eg FOTH, Wilkerson). In fact, boiling point has frequently been used as a method for measuring altiude (it suffers from all of the same problems as barometric altimeters).

From FOTH, 7th ed:

   ft     m    C    F
    0     0  100  212
 5000  1525   95  203
10000  3050   90  194
15000  4575   85  185
20000  7000   80  176

And it takes iodine a while to work.

All treatment chemicals take a while to work. Heating the water after adding the iodine will reduce the time required.

Doug

 

[Snowflea]

Steri-pen

Originally Posted by Stinkyfeet
Anyone here have experience with the Steri-pen? It uses "UV light to destroy waterborne microbes" and is very, very lightweight.


Lawnsale looked it over and reported his results in an earlier thread. A search should find it.

Doug

I was specifically looking for personal experience in using the device.

Here is what Lawnsale had to say about it:

5. Ultra-Violet (UV) aka Steri-Pen. A light emitted at 254 nanometers through a quartz sleeve for a specific amount of time. The light disrupts the DNA sequence of the organism so it cannot reproduce and thus dies off.
a. Pros: Forms no harmful byproducts, water quality from a taste and sight perspective remains unchanged, fast rate (in about a minute).
b. Cons: Certain compounds in the water can absorb the light, making it less effective; dependent on batteries and the unit not breaking down, turbid water can prevent organism destruction by hiding in the shade of the particles, costly ($150), limited life span on the bulb, not sure if it can be replaced (but the bulb life span on other UV systems is very high), does not inactivate certain virus strains.
c. Giardia and Crypto: Effective against Giardia and Crypto.

I would add the "pro" that it is extremely light weight at under 4 oz/110 grams, and also that I recently got mine for significantly less than $150 here:
http://www.zombierunner.com/store/product768.html

I haven't used it yet but plan to use it in the Sierras this summer...

 

[MikeM]

I have purchased a steripen and have used it on 3 trips so far. I previously used iodine,a filter, boiling or used sources that "looked" good. The unit is very lightweight which is great for backpacking and it makes a litre of water suitable for drinking in about 90 seconds. One drawback is that you are supposed to see that the UV light has come on to confirm the unit is working properly. On sunny days I have a tough time seeing the light thru my nalgene bottle. I will probably change to a more translucent water bottle and hope this helps. It's a bit of a mental leap for me to fully trust that the little UV light is killing or rendering harmless all the critters that can make you sick. You also have to be careful about water on the threads and lid as the unit only works on the water in the bottle. So far so good and I am happy with the purchase.

 

[Pete_Hickey]

..... my nalgene bottle. I will probably change to a more translucent water bottle and hope this helps.

Remember, though that opaque, narrow-mouth bottles are best. You can't see what's in the water you're drinking.

I used to have PolarPure, until a concrete floor destroyed mine, too (is that a trend, or anecdotes). Since then, I just look for water I trust.

 

[bikehikeskifish]

Remember, though that opaque, narrow-mouth bottles are best. You can't see what's in the water you're drinking.

We call those "longnecks", Pete

Tim

 

[DougPaul]

I would add the "pro" that it is extremely light weight at under 4 oz/110 grams,

The pro (2 x CR123A batts) is lighter than the regular (4 x AA bats), but the batts are more expensive and less likely to be availible at the trailside store. Take your choice, lighter pack or lighter wallet... Otherwise, the two appear to be the same.

FWIW, rechargable CR123 batts are available.

Doug

edit: I misinterpreted Stinkyfeet's use of the word "pro" to refer to the Adventurer model. My comments are a comparison of the standard and Adventurer models. Her weight refers to the Adventurer model.

 

[una_dogger]

I'm wondering how well the SteriPen actually works in water with alot of dissolved or suspended solids. (as we all know, not all water sources out on the trail are crystal clear!). I know UV sources work well (I had one installed in a previous home) but the water was prefiltered to remove sediment prior to UV treatment.

Maybe Lawnsale will be along soon to address these questions in full detail.

Doug Paul, good points, as usual (and I apologize for the Steripen-slight derailment). My probs in Nepal most likely stemmed from improper food handling; mainly teahouse keepers using fresh water to wash things, cook things, clean things. Also, even though you can buy "safe" boiled water while trekking, fuel is costly and so many times you can't be sure how long the water has been boiled -- or if its actually brought to a full boil.

 

[BIGEarl]

I tend to go through quite a bit more water in warm conditions than during the winter which is probably the case with most people. Consequently, I pack more water at this time of year.

Normally, I start each hike with roughly six liters of liquid (water, Gatorade) and gradually work through this supply in the course of the day. Each liter weighs in at roughly 2.5 pounds (water + bottle + insulated pouch).

I have checked the specifications on various filter systems and find they generally weigh approximately 1 pound, or a little less.

Reducing my carried supply by three or four liters at 2.5 pounds each and adding a filter that weighs in at 1 pound will net a significant weight reduction. This is the weight difference I am concerned with. I’d like to accomplish this reduction and make sure I’m covered for safe water throughout the day.

The differences between possible solutions that represent a couple ounces in net savings aren’t all that important to me.

Based on the posts it seems filtration is the most popular approach for the geographic area of interest (New Hampshire, Maine, Vermont, and upstate New York). A good, compact filtration system with a washable or replaceable filter cartridge is probably the direction I'll take.

I'm sure there are experienced-based opinions on the available filter systems. Are there suggestions concerning the particular filter system to select or avoid? Any additional guidance in this area would be appreciated.

Thanks for all the help.

 

[peakbagger]

Regarding Giardia in the whites.

The Berlin NH municipal water supply which is predominately from the east side of the Kilkenny range had giardia issues back in 1960's, it is a surface water supply in a very remote area. The water supply was closed for years until a new slow sand filtration system was installed in the 90's. Therefore giardia has been around at least part of the whites for a long time. The great gulf area has had confimed cases of giardia in the early seventies (I know two of them).

The general guideline of a lot of working professionals in the area is that if there is a chance of mammals (be it two legged or four legged) in the water shed above the water source, plan on treating it unless it it a true spring. That cuts the safe areas down substantially.

I carry aquamira as its lightweight and relatively low hassle. I used to use Polar Pure but the taste and low effectiveness against Giardia got me to switch. Note that a lot of the ponds in the whites that dont have high water flow, have a lot of very fine suspended solids, that will plug most filters. Having the capability of field cleaning is a must if you go with a filter.