The water cycle is the continuous flow of water from and through the oceans, atmosphere and land. When we learn about the water cycle in school, we tend to think of it on a macro level. We examine how the water in our environment moves from bodies of water to the clouds to the ground and back through this pattern again and again. We learn how water is constantly moving around us.
For the survivor, we must consider the water cycle and how this affects us on a daily basis. We need to think of the water cycle on a micro level. As we go about our day, we lose water through perspiration, respiration and digestion. We consume fluids to rehydrate our bodies and return our system to “normal” or what we believe is properly hydrated. The reality is, many Americans walk around each day partially dehydrated. In the field, we must be more vigilant of our water intake and excretion. We must know various methods of finding water, collecting it, treating it and carrying it. We, like water, must be fluid in how we view it or we will never meet our daily needs.
THE CANTEEN KIT
My good friend, mentor and former boss, Marty Simon of the Wilderness Learning Center, impressed upon me the importance of carrying a canteen everywhere. Whenever we would depart on plant walks or field exercises with our students during week-long survival courses, we would reach for our canteens and ensure they were full. Marty’s canteen was part of his readiness plan and he took his plan to the next level when he started to build his survival kit around his canteen. We developed good water discipline and were far from our canteen. It made sense to keep some basic emergency and survival components handy.
The current canteen kit I carry is an evolution of the one I carried while lead instructor at the WLC. What used to be a stainless-steel Nalgene bottle is now a Heavy Cover Titanium canteen. Both of these had nesting cups in the bottom. The items carried inside or strapped to the outside were purposely included to meet the various “rule of 3s.” An emergency blanket in the bottom of the kit provides a vapor barrier to the elements. A spare ferro rod tucked behind the MOLLE paneling is a backup to what I carry in my pockets. The emergency mirror and whistle are there to grab the attention of rescuers, just in case.
Other items are tucked wherever there is space. These include water purification tabs, extra cordage, a mosquito head net, etc. I make it a point to always have a canteen of sorts on me. Whether I’m commuting to work or in the field, I know the importance of water. Just as I appreciate lunch and pack that, I know I need to meet my water needs and always have a good canteen not far from my person. 
FIND IT
Eventually, the water you carry will run out. A gallon of water weighs just over eight pounds and even the most fit person can’t carry enough to last more than a few days without refilling. Locating water comes down to understanding how and where it collects.
Water flows downhill but this doesn’t mean you should overlook natural hollows in trees that might contain water. I’m sure we’ve all seen water pool in tarps during a heavy downpour. Water does flow downhill and it collects in low-lying areas. If you can identify the right geography from the landscape like valleys, bowls, draws and other natural funneling features, you may find water. If you see moss growing on rocks, the surface may be damp. This can be collected if you are willing to work for it instead of holding out for a larger, more substantial source. In general, vegetation is a good sign water may be present. Understand though, some vegetation can live in extremely arid locations with little water. Standing pools of water can be excellent sources, but the water must be considered unsafe as-is. If you found it, a four-legged animal probably found it, too.
Easily accessible water is best. Tapping trees, using transpiration bags, collecting dew, all of these methods require almost no energy output. I generally don’t teach solar-still techniques because they require a lot of material and generate minimal amounts of water. Remember, the water you use must be replaced. The human water cycle isn’t going to stop because you’re in an emergency situation.
COLLECT IT
In an emergency or in times of dire thirst, we all will imagine finding that perfect watering hole. In a perfect world, we won’t have to treat found water and we can cup our hands in it and bring it right to our mouths. However, water collection may require far less ideal means. By collection, I am referring to the method of taking it from nature and putting it into our control. Other than dipping our hands into water, there are many ways of ensuring water ends up under our control.
When collecting water, you may put the water through a process to filter it without purifying it. Filtering will remove sediment or particulates you may find disgusting to look at as you drink it. A bandana or t-shirt over the top of your container will work. If you are without a spare piece of cloth, a seepage basin dug adjacent to the questionable water source will allow the water to flow through the soil and filter naturally. The water in the hole will be clearest at the surface and should be collected from the top down.
A single strand of paracord can be used to transfer water from a dripping crack in the rocks to our canteens. The water will bead up and follow the cordage. We can collect water using a bandanna if we attach it to our boot and walk across a wet field. We can collect water by tapping a tree and letting the sap flow out. Water can be collected by creating a basin out of an emergency blanket, poncho or contractor bag. If the color of the basin created is black, snow will melt on it during the winter and pool as water in the sunlight.
In urban settings, water can found in many places but not all are safe, due to chemicals. Don’t drink pool water or the water found in toilets. Generally safe is water found in your pipes as well as water heaters. If you are waiting out an imminent emergency like a storm, collect water in your bathtub or in any containers you have. You can’t have enough water.
TREAT IT
In the field, the optimal way of treating water is boiling it. If you are already using a fire to keep warm, you don’t use up any extra resources boiling water. Opinions vary over how long you need to boil it. I bring my water to a strong rolling boil for a minute or two. Some will say, “just to a boil,” while others say, “boil it for 5 minutes,” and others still, “boil it 10 minutes.” At the very least, bring it to a boil and keep it boiling for as long as you feel comfortable. Whenever possible, use a lid while boiling your water as this will increase the temperature, as well as reduce both boil time and the amount of water that will evaporate. Since a fire might not be logistically possible or safe given your environment, it is wise to carry a backup option.
To survive, you may need other one- person methods of treating water. These include chemical tablets and mechanical means in the form of individual-sized purifiers. Iodine tablets work well, but if the survivor is allergic to shellfish, they should not be used. Chlorine-based tablets work exceptionally well but require a longer wait time. Other chemical options include bleach and binary chemical treatments. Filtering devices work, but should not be used in cold temperatures if the filter has a ceramic element. The ceramic can crack in the cold as absorbed water expands. The plastic can become brittle and break as you use the pump, too. The purifying filter can become clogged so make sure you only treat water you’ve strained of large sediment. If you couldn’t tell, these filters have moving parts and each moving part is a liability. All of these secondary methods run out. Tablets are used up and filters become less effective as they come close to their lifespan. Boiling is still the best option.
CARRY IT, CARRY MORE
Your canteen will only carry so much and if you truly are in an emergency, you should have the gear or the know how to carry more. The first place you should consider carrying water is internally. Don’t strike off away from your water source without tanking up first. This means drinking water slowly and over time. Don’t rush to fill up your stomach as you cannot absorb water that quickly. If you have been sweating, you will likely need to consume even more. Avoid drinking too much water as this causes hyponatremia that dilutes your body of essential salts.
After having your fill, you should consider what you can find to carry water in. Reynold’s Oven Bags, Platypus and Hidden Flask bladders, Zip-Lock Bags all hold water just fine. If you don’t have these, you can always improvise with a water-resistant cloth or material like your space blanket or tarp. If all else fails, you can resort to your knowledge of bushcraft and make a container or two out of birch bark (if it is available). No matter how you decide to carry extra water, make sure you are careful with your container. Don’t damage it or drop the water you worked so hard to collect, treat and contain.
One form of water carrier I am not a fan of is the standard unlubricated condom. These will hold close to a gallon of water or more if there is a serious flow of water to stretch it open or if there is a body of water you can forcefully move it through to do the same. The condom won’t work well on a low volume body of water like a quarter-inch deep creek.
The water cycle is a concept we must grasp to pass grade school and it is one we must understand and respect to survive in the great outdoors. By breaking down the water needs of the outdoorsman, one can be prepared for the field and stay hydrated on a daily basis.
Editor’s note: A version of this article first appeared in the How To special issue of American Survival Guide.