Dehydration can ruin a day in the mountains like nothing else. Water is the only thing that can keep you alive while mountaineering. It is easy to fall behind in your hydration on the trail if you are not careful. This can cause your body to shut down surprisingly fast. What is the recommended amount of water to drink while hiking in the mountains? Throughout this guide, you will cover everything you need to know about how much to drink, how to carry it, and where to get it in the backcountry.
Would you like to know how much water you need?
The first thing we should talk about is how much water you actually need to stay hydrated. You can take 0.5 to 1 liters of fluid per hour as a rule of thumb if you’re looking for a quick, simple answer.
Temperature, humidity, wind, elevation, your fitness level, your sweat rate, and how hydrated you were at the beginning of the day all play a role in determining how much water you should drink.

It may be possible to drink half a liter of water every hour to two hours, depending on how much you sweat. As you climb a sunny slope in midsummer heat, you might need more than a liter of water per hour.
To determine how much water you need, you must keep track of how much you drink over the course of your hikes under different conditions.
Do You Need to Carry a Lot of Water?
Mountaineers face another conundrum when it comes to carrying liquids. The weight of water per liter is two pounds, so it’s much heavier than food or gear. If you need six liters of water throughout the day, make sure you plan ahead so that you won’t have to carry it all at once!
It is crucial to plan ahead when deciding how much water to carry. Maps and trip reports can help you find water sources along the route. Then determine how long it will take you to travel from one water source to another, and calculate how much you need to carry. If it is a difficult terrain or you are more exposed to direct sunlight than you anticipate, you should carry a few extra items.
You’ll need a filtration system in order to safely refill water. In addition to pumps and gravity filters, there are squeeze bags and Steripen UV filters. You can use any of these filters to make water found in a backcountry creek or lake safe to drink, so pick whichever option feels most comfortable to you.
In the backcountry, avoid drinking untreated water except in extreme cases. Even though dehydration is bad, it’s still better than getting a parasite like Giardia.
Water Carrying: Bottle vs. Bladder
Another decision you’ll have to make is whether to carry your water in a bottle or a bladder.
Using a bladder is much more convenient for me. While hiking, you can sip from them without taking off your pack, so you are more likely to stay hydrated. In addition, they are made from flexible materials, so they collapse down when you don’t carry much water.

If you use a bladder instead of a bottle, the only downside is that it’s hard to tell how much water is left in it. Over time, you will be able to develop a sense for how much is left – or simply check the level of water in your pack.
The convenience of using a water bottle is that you can drink out of it and refill it with a filtration system. Whenever you drink from a bottle, consider using collapsible bottles to save space in your pack.
In the end, choosing between bottles and bladders comes down to personal preference. Take them both on your next climbing or hiking trip and see which encourages you to drink more.
Electrolytes vs. water
Drinking water is an important part of proper hydration, but it isn’t the only one. While hiking, you should also replenish the salts that your body loses through sweat. Losing electrolytes can be just as hard on your body as losing water.
Snowmelt often results in very low salt concentrations in backcountry water sources. Every time you travel, you’ll need your own electrolyte mix. If you want to keep your water and electrolytes separate, you can mix Gatorade powder or salt tablets into your water or eat salty trail mix throughout the day.
Dehydration Signs
If you don’t drink enough, how can you tell? If you are dehydrated, you will typically experience symptoms such as nausea, cramps, and headaches. The symptoms are mild at first, and should subside once you rehydrate. A dark urine color indicates that you need to drink more as well.
You may notice that your body stops sweating in extreme cases. If you’re not feeling hot, don’t confuse this with being well-hydrated or having lost a lot of heat. It’s a sign that you’re severely dehydrated and your body is trying to conserve water.
Despite the possibility that you can overhydrate, most hikers and mountaineers do not need to worry about this. As long as you’re eating throughout the day, overhydration is unlikely to occur.
Here are five tips for staying hydrated
In the backcountry, hydration is more than just knowing how much water to drink. Check out these five tips to help you stay hydrated.
1. Always have water on hand
When your water is stored deep in your pack, it’s easy to rationalize not drinking. Before you know it, you’re behind on your hydration.
When you can drink without stopping, or can reach your water without opening your whole pack, you are more likely to keep sipping while you hike.

2. Use a timer
When it’s cold, it’s easy to forget to drink. You can keep track of your hydration by simply setting a timer on your watch or phone. A reminder will sound every 20 to 30 minutes to remind you to drink water.
3. Refresh in the morning and evening
When you’re sweating a lot throughout the day, it may not be possible for you to stay hydrated. There is a limit to how much water your body can process per hour, even if you’re sweating out at a higher rate.
Therefore, you should recover in the morning and evening. During multi-day backpacking and mountaineering trips this is especially important. Get your body back to an ideal level of hydration by taking in as much fluid as you can during the hours when you are not moving.
4. Protect yourself from the sun and wind
As you are exposed to sun and wind, your body loses water faster. Particularly sunburn can cause you to lose a lot of water very quickly. You can conserve fluids by using sunscreen or adding a light jacket or hat to your outfit.
5. Drink more water at high altitudes
As you go higher in the mountains, your body loses water more quickly. This is because the air is drier and less oxygen is available for your body to breathe. You should drink an extra liter of water each day if you’re climbing above 10,000 feet. You will also need to consume more electrolytes when you’re at high altitude, even if you’re not sweating as much.
As a conclusion
When hiking or mountaineering, it is incredibly important to stay hydrated. While it will take a few tries to figure out how much water your body needs, you should try to drink 0.5 to 1 liter per day while in the field. Don’t forget about electrolytes and adjust your hydration levels according to the weather and conditions.
Frequently Asked Questions (FAQs):
How much water should you drink while hiking?
“During the hike, a good goal is to drink 6 to 12 ounces of water or sports drink every 15 to 20 minutes and generally, you will want to drink small amounts frequently and take your last sip when you approach the nearest spring.
How much water do I need for a 10-mile hike?
In general, the amount of water you should drink on a 10-mile hike is about 0.5 liters (17 ounces), or 2 cups of water for every hour of moderate-temperature hike in typical terrain. Depending on the surface of the terrain, the weather, and the speed at which you walk, you may need to drink more than 2 liters.
How many liters of water must a mountaineer need in a moderate hike?
The water intake during the trek should be 2 to 3 liters. When you feel tired, take a break and hydrate and when you arrive at your campsite, drink a liter of water in short breaks. Try to drink 6 to 7 liters of water a day.
How much water do I need for an overnight hike?
A good general recommendation is about a pint of water per hour of moderate activity in moderate temperatures. You may need to increase the amount you drink as the temperature and intensity of activity increase. For example, a strenuous walk in high temperatures may require you to drink 1 liter or more of water per hour.
How much water do I need for a 5-hour hike?
If you are planning a 5-hour walk, you will need to bring at least 10 cups (2.3 liters) of water per person. Remember these are just general rules! Some people drink a lot more water. However, it is a good guide.
How much water do I need for a 2-day hike?
A general rule of thumb that many backpackers (including me) follow is to bring 1 liter of water for every 2 hours of hiking.