The best way to clean your water when backpacking is to use and find the cleanest water source possible. You’ll want to look for clear, running water — somewhere between a babbling brook and a rushing river.
Avoid stagnant ponds or areas where there might be runoff (from livestock, urban areas, etc.) or debris. You’ll also want to find a safe place to refill, pump, or hang your gravity filter.
With some filtering methods, like chemical filters and tablets, you’ll want to wait longer to ensure that the water is clean if it’s below a certain temperature (or cloudy).
Purifiers, like the Grayl GeoPress, protect against protozoa or parasites, and bacteria, but you still want to source your water from a fast-flowing stream or river; (photo/Chris Carter)