Most backpackers these days treat their water in the backcountry through a few commonly known options. When I state “treat” their water what I mean is to make it potable or safe to drink.
- The most common option is to use a filter and there’s all kinds of filters. Straw filters, pump filters, gravity filters, bottle filters, squeeze filters, etc. They all have the same basic principle, to remove bacteria from the water.
- Another common option to make water potable is to use chemicals such as iodine or chlorine which kills the bacteria.
- Rounding out the commercial options for treating water is to use a UV filter. Essentially exposing the bacteria in the water to an extended amount of UV light will kill the bacteria.
Having mentioned all of the above, the single most effective way to treat your water is to boil it. All of the options above aren’t as effective as boiling, at least according to a little organization called the Centers for Disease Control and Prevention.
Here’s the fun part. Did you know that water boils at different temperatures based on altitude? At sea level water will boil at 212 degrees Fahrenheit. For about every 500 feet you go up in elevation the boiling temperature goes down just over 0.9 degrees.
So, getting back to the whole point of this article. The CDC recommends you boil water for 1 full minute for elevations up to 6,562 feet. That’s pretty much everywhere east of the Mississippi except for the 7 tallest mountains which are all found in Tennessee and North Carolina. Once you get above that elevation the recommendation is to boil at least 3 minutes.
An additional interesting point is the boiling temperature will go up when you go below sea level. The lowest land point in the US is in Death Valley with an elevation 282 feet below sea level. The boiling temp there would be around 212.5 degrees. The lowest land point on earth is the shoreline of the Dead Sea with an elevation 1,355 feet below sea level and a boiling temp around 214.4 degrees.