Backpacking Gear Part 3: Water Treatment & Transport

Hiking and backpacking, like all physical activities, requires good hydration. On day hikes we carry 1-2 liters each in Nalgene bottles. For backpacking trips, we need more than 2 liters of water which is achieved either by carrying more water or collecting additional water from available sources such as streams, rivers, or lakes. Keep in mind that each liter of water weighs 2.2 pounds, not including the container. This post will look at water treatment options, our choice of treatment method, and the containers we’re choosing for our foray into ultralight backpacking.

Water Treatment

Any collected water could contain pathogens (protozoan cysts, bacteria and/or viruses) that will make you sick if not treated before drinking. If livestock, wildlife, or humans can reach an area, so can contaminants transmitted via their fecal matter. While water may appear pristine, you don’t know what may have contaminated it upstream. There are numerous methods to treat water including filtering, purifying with chemicals, Ultraviolet (UV) sterilization, and boiling. Water with visible matter/debris can be pre-filtered using a bandana or a similar piece of cloth.

Filtering

Water filters work by physically straining out protozoan cysts (such as Cryptosporidium and Giardia lamblia) and bacteria (such as E. coli, Salmonella, Campylobacter and Shigella). These biological pathogens are the main water concerns if you’re traveling in the U.S. or Canada. There are more concerns if traveling to other parts of the world. For those other regions you will want a water purification system, which will filter even smaller pathogens (including viruses) than the filters described here. Every filter and many purifiers include an internal element, a component that has microscopic pores that catch debris, protozoa and bacteria. Over time, strained matter gums up an element’s pores, requiring it to be cleaned and eventually replaced.

A hand pump water filter

The Lifestraw filter

There are many different options on the market.  Straws such as Lifestraw filter as you drink through them, using suction to force water through the filter. Systems such as the MSR Sweetwater Microfilter hand pump water through a filter with a hose pulling water out of the water source and another hose sending the filtered water into your container. Filters such as the Sawyer Squeeze require collecting water into a container and squeezing the water from the container through the filter and into your container. Gravity systems such as the Platypus GravityWorks Water Filter involve collectting water and hanging the container and allowing gravity to force the water through the filter system into another container.

Pros:

• You can process precisely the amount of water you need
• With pumps and straws, water can be pulled from seeps and shallow water sources
• For pumps and gravity filters, the internal element or cartridge is replaceable
• Gravity filters make it easy to process larger amounts of water
• You can drink the water immediately after it is filtered

Cons:

• Pumping can be a chore, especially at the end of the element’s lifespan
• Field cleaning of the element is required
• Weight and bulk are greater than other treatment methods depending on the type of filter system you choose
• Filters can fail in the field

Chemical Purification

Effective against protozoa, bacteria and viruses, you simply add chemicals to gathered water and wait. Products are typically iodine- or chlorine-based and available in drops, pills or gadgets that mix base ingredients. Examples include: Aquamira (Chlorine dioxide drops), Potable Aqua (Iodine tablets), or Katadyn’s Micropur (tablets with Chlorine dioxide).

Pros:

• Easy to use
• Ultra-inexpensive, ultra-small and ultralight
• An excellent backup method to pack in case your main filter breaks
• As long as you have the chemical drops/tablets this method can’t fail in the field

Cons:

• Wait time before drinking is 30 minutes to 4 hours, longer for icy cold water
• Iodine products impart a chemical taste—can be countered by taste-neutralizer tablets
• Iodine products aren’t effective against Cryptosporidium, though they work fine against other types of protozoa
• Iodine products can be a concern to pregnant women and people with a thyroid condition

Ultraviolet Light Sterilization

UV Light Filter- Steripen

Pen-style devices that you place into your water, push a button and stir. Stop when the UV light turns off (60 seconds or so) and you will have treated all the water inside a bottle. UV light filters are powered by batteries. An example is the Steripen by Katadyn which is powered by 2 CR123 batteries.

Pros:

• Treatment is easy and water is quickly drinkable
• No element cleaning and replacement are ever needed

Cons:

• Requires batteries
• Silty or cloudy water impairs effectiveness, requiring you to prefilter
• Multiple treatments are required to produce large quantities
• UV lights can fail in the field

Boiling

Tip: Always carry a backup treatment system. A filter can be lost; batteries can drain; a device can get broken. Chemicals offer extra security with negligible weight. Boiling is a surefire backup option.

What We’re Using

For our foray into ultralight backpacking, we’ve selected to use a filter as our primary method. We’ve selected the Sawyer Squeeze which costs about $30 and weighs about 4.5 ounces (filter + cleaning syringe). As a back-up we will carry a bottle of Potable Aqua Iodine tablets. In the past we’ve used a hand pump filter, which was larger and weighed more.

We’re using the Sawyer Squeeze System

Features of the Sawyer Squeeze System per the manufacturer include:

• Comes with 2 -32 fl. oz. mylar pouches, a cleaning coupling and additional accessories for gravity and/or inline use
• The hollow-fiber membrane filter removes 99.99999% of all bacteria, such as salmonella, cholera and E.coli; removes 99.9999% of all protozoa, such as giardia and Cryptosporidium
• Simply fill up water pouches at a lake or stream, screw filter onto the pouch and squeeze pouch to push water through the filter
• Filter has a built-in push/pull cap so you can spray water straight into your mouth or use it to fill a water bottle; squeeze filter fills most water bottles in only 30 seconds
• Also comes with a syringe to back-flush the filter to maintain a high flow rate
• Filter fits the threads on most bottles of water that you buy at a grocery store
• Avoid freezing this filter; freezing may ruin the hollow-fiber membrane

Water is collected in the 2 liter bladder and then squeezed through the filter into the Smart Water Bottle. We’ve found it easiest to have one person hold the bottle and the filter while the second person squeezes/rolls the bladder to force the water through the filter

The syringe is used to flush filtered water backwards through the filter for cleaning

When we field tested our Sawyer Squeeze, we found that it took us longer than the advertised 30 seconds to squeeze one liter of water, with the time being more realistically in the 2 minute range. We opted not to use the included mylar pouches as they did not get good reviews. People reported that the pouch seams broke while squeezing. We are using a 2 liter bladder made by Evernew, which costs about $28 and weighs 1.5 ounces and gets much better reviews. When we field tested, we discovered that it can be hard to get water to go into the bladder when there is not a strong current and it was hard to fill the bladder more than 1/2 to 2/3 full. We have added a Capri Sun drink pouch, with the top cut off, to use for dipping water out of slower currents or shallow sources.

We collect untreated water into our Evernew 2 liter bladder. A Capri Sun pouch is used to scoop water in low current or shallow water situations and to entirely fill the bladder.

Water Transport

Based on recommendations of multiple articles and blogs by long distance thru-hikers, we are using 1 liter Smart Water Bottles (2 each) to carry in our backpacks as they are lighter than our Nalgene bottles. One Smart Water Bottle weighs 2.6 oz while a Nalgene weighs 6.2 oz. You can purchase Smart Water at most grocery stores and some convenience stores.

We use Nalgene bottles while we day hike and on previous backpacking trips, but each one weighs 6.2 ounces

A Smart Water Bottle with push/pull top and silicone band weighs less than half of a Nalgene bottle

We purchased a $5 Smart Water Bottle Upgrade kit from Gossamer Gear that included 2 push/pull tops and 2 silicone bands which I am using. The silicone bands help with grip on the smooth surfaced bottles. The push/pull tops can’t get dropped or misplaced while getting a drink unlike the normal bottle tops. I can also drink out of them while walking. This is personal preference, Mike tried both and didn’t feel the straps were necessary and doesn’t like drinking out of the push/pull tops.

When we backpack in areas that do not have much water, we own various Platypus and Hydrapak bladders/bottles to carry larger amounts than 2 liters each. We research trips in advance to learn about water sources to figure out how much water to carry for each segment. For example, in the desert we have carried 7 liters each for an overnight trip, that’s 15.4 pounds of water!

Tip: Store water bladders in the freezer between trips. Water bladders can be hard to get completely dried out. They can be stored in the freezer to prevent microbial growth between trips.

Our Water Filtering & Transport Gear Weight:

First Person:

Sawyer Squeeze (including syringe for flushing) 4.5 oz + Evernew Bladder 1.8 oz + Smart Water Bottles 2.6 oz/each x 2 = 5.2 oz,  + Capri Sun Pouch <1 oz + backup Potable Aqua 3 oz = under 15.5 ounces total without water

Second Person:

Smart Water Bottles 2.6 oz/each x 2 = 5.2 oz= 5.2 ounces total without water (No duplicate Sawyer Squeeze/syringe, Evernew, Capri Sun pouch or Potable Aqua)

Check out our other Backpacking Gear posts:

• Backpacking Gear Part 1: Backpack Tent & Sleep Systems
• Backpacking Gear Part 2: Food & Cooking Equipment
• Backpacking Gear Part 4: Electronic Gadgets (Communication and Wayfinding)