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A Hiker's Guide to Potable Water

James is an avid outdoor enthusiast, author, and speaker who regularly chronicles his adventures: hiking, camping, and canoeing.

A Hiker's Guide to Potable Water

Elijah Hiett, Unsplash image

Elijah Hiett, Unsplash image

Potable water is safe for consumption and essential to physical functioning and survival. Water constitutes about 70% of body weight and lubricates tissues of the eyes, nose and mouth and joints. Water dissolves and transports nutrients, minerals and oxygen to your organs and assists the kidneys and liver to flush out waste products.


A person can survive a month without food but only about 3 days without water. Generally, adults need to consume two to three liters of water daily including water from beverages and food. Staying hydrated is essential to temperature regulation which protects against hyperthermia and hypothermia.


When the body is properly hydrated, urine output is normal and the color is transparent to light yellow. A loss of 4% of total body water leads to dehydration. Initial symptoms of dehydration include thirst and reduced urine output which appears darker as it becomes more concentrated. Saliva, tears, and perspiration decrease and the skin may feel clammy. As dehydration worsens, lightheadedness, dizziness, nausea, headaches, muscle cramping, weakness, palpitations, and confusion ensue. Heat stroke and heat exhaustion may follow. In the terminal stages of dehydration, organ failure, shock, and coma are likely to be fatal.

Staying Hydrated

Alan Carrillo, Unsplash Image

Alan Carrillo, Unsplash Image

Hikers may consume up to a liter of water per hour depending on the climate, terrain, and one's physical condition. Pre-hydrating before hiking helps to protect against dehydration. It is also useful to sip water regularly during your hike and supplement with rehydration salts or consume snacks, or drinks that contain electrolytes to replace sodium and potassium lost through perspiration. Electrolytes are chemicals that conduct electricity when mixed with water. They regulate vital nerve and muscle function, hydrate the body, balance blood acidity and pressure, and help rebuild damaged tissue.

When planning your hike it is wise to identify water sources along the trail to replenish the supply you carry. It is useful to remember that water is heavy, weighing 2 lb. per liter and you may need a refill every couple of hours. Therefore access to potable water is a necessity. Water you encounter on the trail from lakes and streams may look clean and refreshing, but in fact, can be dangerously contaminated.


A real threat to consuming water from unknown sources in the wild is contamination from bacteria, viruses, parasites, human and animal waste pesticides, fertilizers, and even heavy metals. These contaminants may be tasteless, odorless and invisible but can cause significant illness and physical symptoms in the form of diarrhea, stomach cramps, and vomiting. Some contaminants such as heavy metals and pesticides may also contribute to long term health problems such as cancer.

Drinking contaminated water or using it for cooking, washing food and dishware, preparing drinks, and brushing teeth can also make you sick. Children, the elderly, pregnant women and people with weakened immune systems may be more vulnerable to illness from contaminated water.

Being prepared to purify water is essential to a hikers skill set.

Wash your hands regularly with liquid sanitizer and keep your cooking utensils, and water bottles clean with biodegradable soap to avoid contamination during food preparation and water purification.


Unsplash Image 9811f2e09048

Unsplash Image 9811f2e09048

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  • Boiling: The most effective way to remove both viruses and bacteria from water is simply to boil it for one to three minutes which will typically make it safe to drink. The most efficient way to boil water is to pre-strain it for solids with a bandanna, or preferably with a coffee filter. Then boil the water in a metal cup or pot from your cook kit. Let the water cool and pour it back and forth between clean containers to improve its taste through aeration.
  • Filtering: Water filters will remove most contaminants such as harmful protozoa and bacteria and carbon improves taste and smell. Some filters utilize Iodine-coated screens that add virus protection. After filtering, the clean water is ready to drink.
  • Chemicals: Germicidal tablets or drops are convenient and inexpensive. They are lightweight to add to your pack and easy to use but require a 30-minute delay before drinking. They may not be safe for pregnant women and some tablets leave a strong negative aftertaste. After dropping a tablet in your bottle and shaking, tip the bottle upside down and unscrew the lid slightly. This will allow the chemical to get onto the threads of the cap. Before consuming, add some Kool Aid or other flavoring to improve taste.
  • Ultraviolet Penlight: This method is effective, lightweight and simple to use. Just turn on the light and immerse the lighted wand in the water source for 90 seconds or the time period specified by the manufacturer. Ultraviolet lights require batteries which may need to be recharged or replaced.

Be mindful of cleanliness and be careful to wash your hands and all utensils, pots or bottles in order to avoid cross contamination.

Summary and Recommendations

Water is essential for healthy functioning. To prevent dehydration, hikers typically consume a litre of water every two hours but climate, terrain, and personal health may increase this amount significantly. Drinks and snacks containing electrolytes aid in rehydration Supplementing the supply of clean water carried requires knowledge of the locations of potable water on the hiking trail and a means of purifying water from unknown sources. Water can be purified by boiling, filtering, chemical additives or ultraviolet light.

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

© 2021 James W Siddall


James W Siddall (author) from Cleveland on April 13, 2021:

Thanks Ravi: Happy you found the article useful. Jim

Ravi Rajan from Mumbai on April 12, 2021:

Very useful information James. I was not aware that ultra violet light can be used as a portable source for cleaning water on the fly. That sounds like one of the safest options to me.Thanks for sharing.

James W Siddall (author) from Cleveland on April 12, 2021:

Hi: Thank you for your feedback. Glad you found it useful! Jim

Sp Greaney from Ireland on April 12, 2021:

I wasn't really aware of all the different ways that you could purify water when outside.

This is really useful advice for anyone planing a trek in the wilderness.

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