Chapter 49: How to Use a Water Filter

Using and caring for a water filter is pretty simple. I’d like to talk about 3 popular, lightweight backpacking filters and how to use them.

The first is the McNett Frontier Emergency Water Filter. It weighs just 6/10s of an ounce and filters down to 2 microns, small enough to remove giardia, cryptosporidium, and bacteria such as E coli.

You fill your container and just use the filter like a straw. Allow the filter to air dry for 48 hours before storing. It costs about $10.

The second filter is the Timberline Water Filter. At 5.3 ounces, it’s about the lightest of the pump filters. It’s simple to use, and can even be used like a straw if you want to leave the weight of the filter home. It costs about $25. Replacement filters are about $15.

To increase the life of any filter, and reduce clogging and keep a good flow rate while pumping, use water that is as clean as possible. Even with water that looks clear, filter life will be extended if you allow the particulate to settle in a container or pre-filter the water with a cloth or a coffee filter. Rushing mountain streams carry a surprising amount of sediment and debris.

To use the Timberline, attach the filter to the bottom of the pump and place it in the water source. Attach the long tube to the pump handle and place the tube into your clean water container. Pump the desired amount of water with a slow, steady motion. It’s preferable to keep the pump vertical.

When storing your unit, keep the clean water tube away from the filter element.

To extend the life of the filter, flush the filter element with diluted bleach, (1 teaspoon household bleach to one gallon of water). Keep the filter in the refrigerator for short-term storage. If the filter is to be stored for more than 2 months, the filter element should be dried. Flush the unit with distilled vinegar (2 tablespoons per cup of water). Allow the filter element to dry in a warm place for 5-7 days.

Like the Timberline, the Katadyn Hiker gives you a fast flow of water and it’s easy to use. It weighs 11 ounces and costs about $60. The Hiker has been the most popular filter for backpackers for several years. It comes with a nylon carrying case, an inlet hose with a weight, prefilter, and float which connect to the pump and filter cartridge, an outlet hose (with a bag to remind you to always keep your outlet hose away from the clean parts of the filter), a bottle adaptor for attaching to large-mouth bottles, an adaptor for connecting to hydration bladders, and some silicone lubricant for when the handle gets hard to push. There are caps to cover the inlet and outlet parts of the filter when not in use.

Adjust the float to keep the pre-filter off the bottom of the water source. To filter water, just place the intake hose in your water source and pump the desired amount of water. Pump the filter until it’s empty of all water, so you’re not carrying extra weight.

To clean, twist to remove the cartridge and simply swish back and forth in water to remove surface sediment. Unless you are filtering very clean water, at some point you’ll have to replace the filter, but this method should get you through your current trip.

For long-term storage, add 2 tablespoons of household bleach to a liter (or quart) of water and pump all this water through the pre-filter, filter, and hoses. Continue pumping another 5 to 10 strokes to remove remaining water from the pump body and hoses. Remove the cartridge and allow to dry thoroughly.

It’s nice to know you can always enjoy clean water when you’re hiking. For more information on all water treatment methods see our chapter 29.