Avoiding Waterborne Illness While Trekking Off the Grid

Avoiding a Cocktail of Bacteria, Viruses, and Parasites while Trekking in the Backcountry

Spending time away from the confines and clatter of civilization, high up on the mountain trails or far away on the sand-swept desert trails, then you know how important water is to a successful trip. The human body is a giant bag of water—we’re 60 to 70 percent of it—and that bag must be refilled frequently. Sweat, digestion, removal of cellular waste, and our very lives depend on it. And it must be fresh water too. In the back-country of North America, water is a readily available commodity, as the climate of most of the wilderness is the perfect atmosphere for streams, creeks, and rivers flowing with fresh water, especially in the springtime when snowmelt cascades into the valleys.

However, how do you know that the next mouthful isn’t going to be swilling with bacteria, viruses, protozoa, parasitic worm eggs, and chemical contaminants all ready to wreck havoc on your body? Drinking contaminated water directly or ingesting secondarily while washing your face or swimming can only compound your problems. What may appear to look and smell like fresh drinkable water may be saturated with all types of parasitic micro-organisms and various harmful bacteria. The last thing you want to concern yourself with when you’re hundreds of miles from home are the nasty affects contaminated water will have on your digestive and nervous systems.

“AT REST, AN AVERAGE MAN NEED ABOUT THREE LITERS OR WATER A DAY, WOMEN NEED 2.2.”

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Dangers Lurk in Water

Toxic algal blooms; bacterial spores such as Campylobacter jejuni, Salmonella, Shigella, and Escherichia coli; viruses such as rotavirus, norwalk virus, and hepatitis A; parasitic worms like cestodes (tapeworms) and trematodes (flukes); and industrial toxins such as lead, mercury and cadmium all lead to unhealthy and potentially deadly drinking water. In North America, there isn’t much worry about parasitic worms, but if you are wheeling abroad, it is a big concern. As well, chemical contaminants are few and far between in North America, especially in recreational wilderness areas, but the complex parasitic protozoa are especially prevalent in most water found in nature. Many, including Giardia lamblia, Cryptosporidium parvum, and Entamoeba his-tolytica, transform from free-living forms into dormant but highly infectious cysts when expelled in the host’s feces.

Cysts are usually round or oval shaped and have tough shells allowing them to survive long periods in water sources while they await ingestion by a suitable host in which they can reactivate into free living organisms and reproduce.

Compared to viruses, and even most bacteria, parasitic protozoa will wreak havoc on your digestive system.

Giardia lamblia is the most well known risks to drinking backcountry water. It is a protozoan parasite that enters the water via the feces of mammals and then attaches itself in the small intestines. It can cause diarrhea, vomiting, bloating, and weight loss.

Cryptosporidium parvum is another protozoa species that populates fresh water in North America via the same method as Giardia. The results of ingesting water infected with C. parum is tremendous diarrhea.

If you drink unfiltered water from a stream or river, you might soon realize that you didn’t pack nearly enough toilet paper for what will lay ahead of you.

Concentrations of cysts vary depending on the water source and the exact location of feces in the water. On average, concentrations in water in wilderness areas of North America are usually below one cyst per liter of water. How-ever, water in a beaver pond, for example, can average well over 100 Giardia cysts per liter. Raw sewage or run-off from land populated by cattle infected with Cryptosporidium can exceed 5,000 cysts per liter.

In 1996, spring run-off in Cranbrook, British Columbia, flushed infected cattle feces into the town’s reservoir, which caused a massive outbreak of cryptosporidiosis that involved several thousand people. In 1993, in the largest ever North American outbreak, 400,000 people became infected with Cryptosporidium in Milwaukee, Wisconsin, from contaminated drinking water.

Adding to the potential for severe outbreaks is the strong resistance of Giardia cysts and total immunity of Cryptosporidium cysts to the chlorine used to treat urban drinking water.

Getting Thirsty?

When thirst strikes, the countdown clock begins. Did you bring enough water? Your window to live without water is only four or five days depending upon your environment, your physique and your energy output.

A possible solution is to carry enough bottled/filtered water with you that will last the duration of your trip, but what if you break down and you are stuck by the trailside in a dead Jeep? You can’t possibly know how long you could be there. It could take days for you to hike out of the hills or weeks for rescue to find you. What then? Your bottle water will have run out and you may slowly die of thirst. A person’s water consumption needs depend on altitude, temperature and the physical activity a person is engaged in. At rest, an average man needs about three liters of water a day, women need 2.2. A liter of water weighs roughly 2.2 pounds, so carrying enough water to last three days will add nearly 20 lbs of weight to a man’s pack.

It may not be a big deal to stash a few gallons of water in your rig, but the best solution is to have a way to filter the water on the go. Carrying a water treatment system is much lighter than bringing all the water you need. And with a treatment system, you need only carry enough water to get you from one source to the next. Don’t leave your survival to chance; hoping to find untainted, fresh water—because you won’t.

There are dozens of filters and chemical treatment options on the market for a wide range of situations and needs: pump filters, gravity filters, filter straws, chemical drops and UV lights.

“IT MAY NOT BE A BIG DEAL TO STASH A FEW GALLONS OF WATER IN YOUR RIG, BUT THE BEST SOLUTION IS TO HAVE A WAY TO FILTER THE WATER ON THE GO.”

Selecting a System

Selecting a water treatment system is even more overwhelming than selecting proper tires to climb over the boulders. Like tires, there are numerous factors to consider, from the basic categories of size, weight and treatment time of each system to more complicated categories such as filter medium, longevity of the system and what types of organisms each system is effective at eliminating. Water treatment systems can be classified into three categories.

Filters: They do well at eliminating bacteria and Cryptosporidium but not viruses. They strain out particulate matter (plants, bugs, and dirt) and usually improve the taste of the water.

Chemical Treatments: They eliminate bacteria and viruses, but they eliminate Cryptosporidium usually only after extended time in the chemical solution. Chemical treatments do not strain out particulate matter (plants, bugs, and dirt), and they usually have a negative affect on the taste of water. Plus, you’re adding chemicals to your body.

UV Purifiers: Interestingly enough, UV light treatments do not actually kill pathogens. Instead, they disrupt the DNA of the organisms so that they cannot reproduce. The downside is that after you’ve treated the water and allow it to sit in sunlight for a long period of time, the organisms can rejuvenate. The EPA approves of the UV process as a purifier (used in commercial applications), but does not actually approve of specific UV devices that consumers can carry.

A much more important aspect to general needs is the time before drinking, or the time each method needs to be effective. Some are immediate, like the filter bottles and pumps, while tablets and chemical drops can take up to four hours. Usually time is of the essence.

Unless you’re base camping in a remote area for days at a time, longer methods are acceptable, but if you’re on the run or need to extricate yourself from a dangerous situation, you will need to get water as you go and won’t be able to afford to waste time sitting around waiting for your water to be ready.

There are other considerations when selecting a filtration system: How much water do you need to treat? Some can only accommodate a liter at a time (such as the canisters), while others have a never-ending supply. Collecting water for a group of people one bottle at a time can be tedious and inefficient, while gravity-fed filters have the ability to collect and treat a lot of water quickly, which is great for groups.

If you are going with a filter-style pump/gravity fed system, consider the advertised micro size rather than the filter medium, the material that actually filters out the impurities. Micro size is a measurement of the pore size in the filter media. Essentially, the smaller the pore size, the more pathogens the filter can strain out. A simple rule of thumb is that the smallest bacteria is 0.2 microns, so a filter should be around that size or smaller to be the most effective.

Other Methods

While it can be wishful thinking to believe that every eventuality can be accounted for when you’re days from civilization, this is just not the case. There are several alternative ways to clean the water you need if you are stuck without proper filtration. The first of these is the most simple and most obvious: boil it over an open fire. Heating the water above the boiling point of 212°F will kill the most lethal organisms—but does nothing to reduce the levels of harmful chemicals that may be in the water.

Another method that is useful for purification when no specialized equipment is handy is an in-ground solar still. A clear plastic sheet stretched over a small pit in direct sunlight will start producing condensation quickly. The object of this is to collect moisture from the soil or surrounding vegetation, so adding plant life to the pit is a way to generate additional liquid. At the center of the pit place a small bowl and depress the sheet so it creates a cone shape; a stone can be placed on the sheet over the bowl to direct the water into the bowl. Solar radiation will then condense water from the soil/vegetation and it will drip into the bowl. Adding unclean water, urine, or other liquids into the pit can increase the amount of useful water produced by the still.

There is nothing more important in a survival situation than access to a viable, clean water source. Water is life, as it is said. While it is important to prepare for the worst while planning for the fun, having a useful filtration system handy or learning techniques about filtering and purifying water can be a lifesaver. Of course, coming back alive is the most important thing.

Waterborne Illness

Dysentery is a major risk for survivalists drinking unpurified water and is characterized by frequent passing of feces, blood, and mucus. It is a prominent risk all around the globe, though primarily in developing countries. It is primarily caused by two main organisms, a bacterium called Shigella and an amoeba.

160,000,000 Dysentery worldwide

600,000 Dysentery resulting in death

30,000 Dysentery cases in the U.S