Sunday, January 27, 2013

Wilderness Survival - Part 5.5: Wilderness Water

Safe Water in the Wild

In our previous post we visited many fascinating aspects of water with the intent of increasing our appreciation for clean, natural water and all that it means to us.  Water is critical for life, mysterious in its properties, and poetic in its several forms.  Protecting water should be a high priority for all of us.  Whether you are in an area with plenty of water or an arid locale where water is scarce really should not change your view of this life-giving liquid.  Water should be cherished and efforts taken to keep the water as pure as we reasonably can.  Water really matters.

So what makes water safe to drink or dangerous?  How can we make dangerous water safe?  Where should we look for water in the wilderness? 

Pure water is safe to drink.  Water full of minerals and other contaminants can also be safe, but that depends on many factors.  In brief, what makes water dangerous is not necessarily how “dirty” is seems but what kind of contaminants are in it.  Bacteria, viruses, giardia, protozoa, heavy metals, poisonous chemicals, parasites, cryptosporidium, and even radioactive isotopes can be present in water and turn a nice wilderness adventure into long-term misery or even death.  Our eyes cannot see these threats and sometimes our noses cannot smell them.  To stay safe, one should select conservative sources for drinking water and one should always take measures to assure water safety before drinking it.

Safer water sources:

As a rule, water will be more pure at its source.  Rain water is safer than river water.  Spring water is safer than streams or creeks.  Snow melt is safer than pond water.  When in doubt, go to the source.  The closer to the source that you get your water, the cleaner it will likely be.  That does NOT mean that all snowmelt, rainwater, or spring water is reliably safe.   But these sources are much more likely to be safe.  When choosing water to drink, ask yourself the following questions:
     1)      How close to the source am I?
     2)      Are there any dead animals near the water or upstream?
     3)      Is the water full life such as fish and aquatic insects?  Are the plants growing near the water healthy?
     4)      Are the rocks in the stream discolored?  If so there is likely high mineral content in the water which could be a hazard.
     5)      Does the water have an odor?
     6)      Is the water flowing or stagnant?
     7)      Are there industries, mines, dumps, or septic systems that may contaminate this water?

Answering these questions will lead explorers to cleaner water sources.  I have risked drinking untreated water from excellent sources when necessary and I have experienced no ill effects.  It is not a good idea, however!  And keep in mind that water that is clean one day can be deadly the next depending on runoff conditions.  Also note that in a survival situation, when you get seriously thirsty, you will drink stagnant mud.  I did not say you should drink mud, but you will if you are thirsty enough.  So it is critical to find water before your thirst is extreme and to take steps to make the water as pure as possible before drinking it.

Water purification:

Water can be made much safer with just a few simple precautions.  Obviously, find the best source of water that you can, then treat the water to make it safer.  There are scores of good camping water filters that can be used to clean up the water.  Some filter out dirt, parasites, protozoa, bacteria and cryptosporidium.  Others will have activated carbon that will also remove much of the minerals and radioactive isotopes.  Few can remove viruses due to their extremely small size.  The good news is that viruses are DNA specific.  What that means is that a virus that will make a deer sick will rarely make a human sick.  So even if we ingest viruses, they will cause no harm unless they are adapted to humans.

I will not take the time and space here to go into manufactured water filters except to say that you should take one into the wilderness with you, and I have found the bag style gravity feed filters are much easier to use than the hand pump varieties. 

But what happens when there is no filter?  Then what?  Water can be chemically sterilized or sterilized by boiling.  Using chemicals, such as chlorine or iodine, to purify water will usually kill most of the viruses, protozoa and bacteria, but if the water is too dirty, then these critters can hide in the solid particles and escape the chemical bath.  What’s more, the concentration of chlorine required to kill cryptosporidium is also dangerous for humans.  Again, chemically treating water will not remove heavy metals and the chemicals used to sterilize the water can combine with other chemicals in the water to make even more dangerous toxins.  And remember that if you chemically treat the water, you will generally be drinking the chemicals used.

(As a side note, why is cryptosporidium so hard to kill?  Cryptosporidium are parasitic protozoa that travel via the fecal-oral routes as oocysts.   These oocysts are extremely robust little packages of genetic material that are not easily defeated.  These hard packets protect the material inside under some very extreme conditions.  Matter of fact, it is theorized that cryptosporidium may have been blown to the upper atmosphere and may have actually scattered from Earth throughout the solar system.  Someday we may find these protozoa on Mars for instance.  Wild, huh?)

Boiling water will kill viruses, bacteria, protozoa, and even cryptosporidium, but it will not remove heavy metals nor many dangerous chemicals.  Water needs to be boiled for one minute at low elevations to wipe out the bugs, but as one’s elevation increases, the boiling point of water decreases, so longer boiling times are needed.  Add roughly one minute for every thousand feet of elevation, or just plan on ten minutes of boiling.

Since neither chemically treating water nor boiling water will get rid of heavy metals and chemicals, neither stand alone as 100 percent effective.  This is why selecting water from a “safe” source is important.  It is also why filtering the water before other treatments is also recommended.  It is not difficult to make a filter in the wilderness that will remove sediments and chemicals from water.  These filters should not be trusted to remove germs, so the water should still be boiled or chemically treated. 

How to make a water filter in the woods:

To make a filter in the woods, it is best to have some sort of cylinder on hand.  This can be a challenge.  A water bottle, two liter bottle, milk jug, coffee can or bucket will all work.  If none of these can be found, then you have finally found a true wilderness area to enjoy.  Good for you.  But then finding the cylinder will be a bit tougher.  A hollow log can be used.  There are several “filter” designs, but all depend on a series of gravel and sand packed into a tube with a charcoal stage in the middle.  Cloth or grass can be used as a first stage to pull out the larger material in the water.  The increasingly finer particles screen all but the really tiny stuff out of the water.  The charcoal will absorb many of the chemicals in the water, too.  Be sure that the sand and charcoal are packed tightly so water does not just run around the outside edges. 

When using a filter like this, it is best to continue to run water through the filter until the water starts running clear.  At first the water will be washing the sand and rocks.  Once the water runs clear, then it is ready for use.  Again, water from the filter should still be boiled before drinking.

Less obvious water sources:

Dew collected with a rag or bandanna
Solar still
Steam collected from boiled salt water
Liquids squeezed or drained from vegetation:  vines, cacti, tubers, coconuts.  (Local knowledge of plants is critical for safety before attempting to get water from plants.)
Use tubing to gather water from difficult to access places like cracks in rock.

How to make a solar still:

To make a solar still, tubing, a large sheet of plastic, and a container are needed.  Dig a hole around three feet deep and three feet wide.  Place green and/or wet vegetation in the bottom of the hole.  Place the container in the center on the bottom of the hole, and brace it so it will not fall over.  Run tubing from the container up and out of the hole.  Cover the hole with the plastic, and trap the edges down with rocks or dirt.  Place a stone in the middle of the plastic centered over the container.  The sun will evaporate moisture from the plants and soils in the hole.  The cooler plastic will cause the water vapor to condense and run down the plastic into the container.  You can collect or drink the water directly by using the tubing.  The water in the container will be clean to drink as long as the container and plastic are clean.  This method can also be used to distill urine or non-potable water into pure drinking water.  Depending on the conditions, multiple stills may be required to distill enough water to keep up with hydration demands

Planning ahead:

Most tasks take longer in the woods.  In our society we are accustomed to heating food in a microwave oven, getting water from a tap, and heating our homes at the twist of a dial.  When we return to the wilderness, we find that basic things like shelter, food, water, and fire all take considerable amounts of time.  We have to adopt a different rhythm in nature, and a big part of that rhythm is planning ahead.  Since it may well take an hour to purify some drinking water, start solving the water challenges early.  And finding a clean source of water can take much longer.  If you find yourself in a survival situation, prioritize water right behind proper shelter.  Solve the water challenges early.

And enjoy the new rhythms that nature encourages.  Don’t make the mistake of expecting the wilderness to be convenient and then stressing when simple tasks take a lot longer.  Seek to enjoy the processes of wilderness living.  Don’t fixate on only getting the end result.  Find peace in each activity and harmonize with nature’s song.  Take time to truly appreciate simple, life-giving resources.  Celebrate water.  Protect it.  Respect it.

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