When exploring the great outdoors, people have to plan on having enough water for drinking. If you are taking long hikes where there is no water, you have to carry your own, and water is heavy. If you plan on hiking around lakes and rivers, there are a few ways to make that water potable.
How can you make lake water potable?
Boiling is the best way to make lake water potable, by disease-causing organisms like viruses, bacteria, and parasites. Never drink water from a natural source that you haven’t purified, even if the water looks clean. There are also products like water purification tablets, ionizers, UV water purification systems, and large water purification vats.
The Center for Disease control recommends that except for boiling, few of the water treatment methods are 100% effective in removing all pathogens. But, there is not a consensus on how effective the other methods of water purifications actually are. This article attempts to shed light on how water purification methods work.
If you want to use a natural water source, start with a clean disinfected container. Wash your hands with soap and water or use hand sanitizer before collecting water so you do not contaminate it. Collect your water from higher elevations or near the water’s source, away from established campgrounds, and away from animal grazing areas.
Try to collect water from moving streams and rivers or from the top few inches of lake water. Dip your container just under the surface of the water and collect from there. The next step is to filtrate the water, but filtration does not purify water. Most water filters are made of a screen with many tiny holes in it. Filters can remove protozoa and some bacteria, but they cannot filter out viruses.
Viruses are too small to filter out of natural water sources. Filters only remove leaves, dirt, sand, and silt. Filtration systems with absolute pore size less than or equal to 1 micron filter are best. NSF Standards 53 or 58 rated “cyst reduction/removal have a high effectiveness in removing cryptosporidium and giardia. Use and care for filters according to manufacturer’s directions, or they will not work well.
Residential drinking water filters are covered by two industry standards: NSF/ANSI Standard 42 and NSF/ANSI Standard 53. The standards are identical when it comes to evaluating the materials safety and structural integrity of a filtration system if they are connected to a pressurized supply like your sink faucet. But each standard covers a different type of chemical reduction performance testing. Standard 42 covers taste and odor. Standard 53 addresses health-related claims.
Make sure to use a NSF/ANSI Standard 53 filter for natural water sources. Next, you need to boil the water or treat it with a disinfectant. This is the most important step for safe drinking water. High temperature and boiling time are extremely important to kill organisms in the water effectively. You will need some kind of fuel to boil the water, whether it is a campfire or a propane stovetop and a container.
If you’re at an elevation below 6,500 feet, put the water in a container over a heat source, such as a campfire or propane stove, and bring to a rolling boil for 1 minute. If you’re at an elevation over 6,500 feet, bring the water to a rolling boil for 3 minutes. Now the water is ready for drinking or cooking.
Drinking untreated water can lead to illness ranging from mild gastrointestinal symptoms like nausea, vomiting, and diarrhea to more severe illnesses like hepatitis, meningitis, and even death. If you drink bacteria-infested water, the organisms can embed in your digestive tract and replicate. Never take a chance with natural water sources.
What Are Other Ways to Make Water Safe for Drinking?
The active ingredient in water purification tablets is typically chlorine, chlorine dioxide, or iodine. These chemicals deactivate bacteria, viruses, and parasitic protozoans, which render them harmless and make water safe for consumption. Potable water purification chemicals are available in tablet, liquid, and powder form.
You can also make your own chlorine solution to purify water. It is highly recommended to wear eye protection in a well-ventilated area when making this solution. You can use granular calcium hypochlorite or common household iodine, also known as tincture of iodine.
Add one heaping teaspoon or approximately ¼ ounce of high-test granular calcium hypochlorite (HTH) to two gallons of water and stir until the particles have dissolved. The mixture will produce a chlorine solution of approximately 500 milligrams per liter.
To disinfect water, add one part of HTH chlorine solution to each 100 parts of water you are treating. This is about the same as adding 1 pint, or 16 ounces, of the chlorine solution to 12.5 gallons of water. If the chlorine taste is too strong, pour the water from one clean container to another and let it stand for a few hours before use.
To use tincture of iodine, add five drops of 2% tincture of iodine to each quart or liter of water that you are disinfecting. If the water is cloudy or colored, add 10 drops of iodine. Stir and let the water stand for at least 30 minutes before use.
You can disinfect water with tablets that contain chlorine, iodine, chlorine dioxide, or other disinfecting agents. These tablets are available online or at pharmacies and sporting goods stores. It is extremely important to follow the instructions on the product label. Disinfection with iodine or chlorine is not effective in killing Cryptosporidium.
Disinfectants destroy harmful organisms by acting directly on them. Disinfectants have a shelf-life, which vary. The length of time for them to dissolve fully so that they are effective also varies. Other factors affect how well each chemical will destroy the organisms include temperature, PH, cloudiness of the water, and how long the chemical is left to dissolve and fully take effect.
Disinfecting Water Using Household Bleach
Use regular, unscented chlorine bleach products that are suitable for disinfection and sanitization as indicated on the label. The label will list that the active ingredient contains 6 or 8.25% of sodium hypochlorite. Do not use scented, color safe, or bleaches with added cleaners. If water is cloudy, let it settle and filter it through a clean cloth, paper towel, or coffee filter.
Bleach also has a shelf life. As every month goes by, bleach becomes weaker and weaker. Bleach should be stored at room temperature for less than a year, or what the product label suggests. You add bleach to the water and let it sit for 30 minutes. Then, if the chlorine odor is too strong, let it sit another 15 minutes. If the taste is still too strong, let the water sit for a few hours.
Volume of Water Amount of 6% Bleach to Add* Amount of 8.25% Bleach to Add
- 1 quart/liter 2 drops 2 drops
- 1 gallon 8 drops 6 drops
- 2 gallons 16 drops (1/4 tsp) 12 drops (1/8 teaspoon)
- 4 gallons 1/3 teaspoon 1/4 teaspoon
- 8 gallons 2/3 teaspoon 1/2 teaspoon
Gravity Water Purifiers
In gravity-based purification, water flows from a top container, which stores input water, to a lower container, which stores filtered water under the effect of gravity. They fall under the non-electric water purification category because they do not need to be connected to any power source to purify water.
Gravity water purifiers use activated carbon and UF or Ultra Filtration. They have drawbacks. They do not filter heavy metals and do not remove disease-causing microorganisms as effectively as UV purifiers, plus they have a low-flow rate. They work well for eliminating physical impurities but do not work for highly contaminated water that has harmful metals.
UV Water Purifiers
A UV water purifier treats micro-biologically unsafe water with germicidal ultraviolet light. The UV wavelength scrambles the DNA of living organisms in the water, so they can no longer reproduce and make you sick. Ultraviolet radiation renders bacteria, viruses, parasites, and fungi unable to replicate by damaging the nucleic acids of their DNA.
What Are the Organisms that Will Make You Sick?
Protozoas Cryptosporidium and Giardia Intestinalis are the most common organisms in lake water that can make you sick.
Potential health effects from ingestion of water contaminated with cryptosporidium and giardia intestinalis are gastrointestinal illnesses, which can cause diarrhea, vomiting, and cramps. The sources of cryptosporidium giardia intestinalis in drinking water are human and animal fecal waste.
Methods that may remove some or all of Cryptosporidium from drinking water are a rolling boil for 1 minute, which has a very high effectiveness in killing Cryptosporidium. Filtration has a high effectiveness in removing Cryptosporidium when using an absolute less than or equal to 1 micron filter like a NSF Standard 53 or 58 rated “cyst reduction/removal” filter.
Disinfection with chlorine dioxide has a low to moderate effectiveness in killing cryptosporidium. Combination filtration and disinfection has a very high effectiveness in removing and killing cryptosporidium when used with chlorine dioxide and an absolute less than or equal to 1 micron filter, NSF Standard 53 or 58 rated “cyst reduction/removal” filter.
Campylobacter, Salmonella, Shigella, and E. Coli bacterias cause the same symptoms as the protozoas. Disinfection with chlorine dioxide has a high effectiveness in killing bacteria. But, a combination filtration and disinfection system has a very high effectiveness in removing and killing bacteria when used with iodine, chlorine, or chlorine dioxide and an absolute less than or equal to 0.3 micron filter, or a NSF Standard 53 or 58 rated cyst reduction/removal” filter.
As you can see, purifying water can take time. You need to figure out what method will work best for your primitive adventure in the time you have and what you can carry with you. Check out REI for water purification needs. REI sells various water purification products online here.