How Much Water Do You Need for Day Hiking?

It’s important to bring water with you when you go day hiking to replace the fluid you lose to perspiration, help keep you more alert and flush waste products out of your body.  Not bringing enough water can lead to discomfort, while bringing too much can slow you down. How much water do you need and what’s the best way to carry it?

1 Liter every two hours

If you’re actively hiking, it’s good to drink about 1 liter (32 ounces) of water every two hours. That’s a good rule of thumb based on my experience hiking year-round and in a wide range of climates. You might need more or less depending on the temperature, humidity and body weight, but that’s a good estimate of what you’ll need to carry if you can’t refill on your route.

Water bottles are best carried where they are easily accessible on the outside of a backpack rather than being buried inside it. Backpacks with stretch side pockets are convenient, so you can reach back and grab a bottle to sip from while walking. Can’t drink and walk at the same time? Stop for a few minutes every hour and sip from a water bottle while you take a five minute break.

How do you know how much water to bring?

If you have a guidebook, it should give you a time estimate for your hiking route. If you just have a map, calculate the total distance of your hike. Divide that number by your pace in miles per hour. This will usually be somewhere between 2 or 3 mph. For example, I can hike 3 miles per hour on a flat trail. If the distance of my route was 9 miles, I’d want to bring 3 liters. It’s just an estimate of what I need, but fairly accurate.

Does it have to be water?

No. You can drink any non-alcoholic fluid. Water is usually cheap and easily available, but you can also drink tea or juice if you prefer, or add an electrolyte mix to your water to make it taste better.