Water for Day Hikers: What to Pack, Why, and How Much

Water on your day hikes – this is such an important topic! Unfortunately, I see so many beginner and experienced hikers out on the trails not prepared when it comes to water. Why is it so important? How much water should you carry on a hike? How do you carry it? What if you run out? I’m going to answer these questions and more in this blog post.

This post may contain affiliate links. Read my full disclaimer here. 

water for day hiking thumbnail

Why is water so important on your day hikes?

3 days

Did you know that humans can survive about three days with no water – only 3 days! Being able to stay hydrated on the trail should definitely be a priority.

Now, that 3-day generalization is assuming that you’re hydrated when that countdown starts. Most of us are not hydrated at any given moment.

We drink tons of coffee and soda, and things that are actually dehydrating us, and we’re not drinking enough water.

In reality, that 3-day window is probably a lot less.

So, what are some of the things we can do to better prepare for a day hike and stay hydrated while we’re on a hike?

Prefer to watch it?

Check out the YouTube video below for all the details!

What Not to Do

I recently went on a hike with a friend that was about 7 miles with 3,000 feet of elevation gain in the middle of summer.

We get to the trailhead at the same time as another group doing the hike.

Only 1 person in the entire group was carrying a backpack and water. Everyone else was carrying literally nothing!

No water and no other essential hiking gear. This is something that I see happening a lot.

Water Bottles

The second most common thing I see is hikers carrying just one water bottle in their hands while they’re hiking.

While I guess that’s probably better than nothing, it’s still a limited amount of water, and probably not enough for the duration of the hike.

Not to mention, it can be annoying to hold it the entire time. You also have no way of getting more water if you run out.

Sometimes, people pack water bottles in their backpacks while they’re hiking so they don’t have to hold them in their hands.

This is not a great system in my opinion because now, every time you want to drink, you need to stop and dig your water bottle out of your bag.

That’s probably not something you’re going to stop to do often, and therefore, you won’t end up drinking frequently enough to stay hydrated.

women day hiking in utah

How to Carry Water on Day Hikes

This brings me to what I use to carry water on my day hikes.

I use something called a water reservoir or a bladder.

They come in different sizes and there are many benefits to using one:

  1. They hold a lot more water than a single water bottle. (I have a 2L size.)
  2. They easily fit into your backpack.
  3. It’s very easy to sip on water and drink frequently throughout the hike without having to stop.

Not only can I carry 2 liters of water easily in my backpack, but I also end up sipping on water frequently throughout my hike.

Gear Highlight:

HydraPak 2 L water reservoir
HydraPak 2 L water reservoir for hiking
Osprey Sirrus 24 L day hiking backpack
Osprey Sirrus 24 L day hiking backpack
blue Osprey Sirrus 36 L day hiking backpack
Osprey Sirrus 36 L day hiking backpack

How Much Water Should You Carry?

How much water you carry will depend on factors such as the time of year, length, water availability on the trail, and duration of your hike.

We’ll talk more about water availability and safe drinking water below.

According to an article on REI.com, “A good general recommendation is about a half-liter of water per hour of moderate activity in moderate temperatures.”

I typically fill up my water reservoir completely, unless I’m certain of water sources along the hike.

Carrying the water weight doesn’t bother me. I’d rather carry extra than not have enough.

In general, I think listening to your body and developing the habit of sipping on water frequently throughout the hike is more important than trying to stick to a rigid rule, but it can be a helpful guideline as you’re getting started.

Please note that the recommendation is for “moderate activity” in “moderate temperatures”.

Amanda using a Sawyer Squeeze to get more drinking water on a hike

How will you get more water on the trail?

So the water bladder makes it easy for us to carry a lot of water and drink it frequently throughout the hike, but it’s still a finite amount of water.

What if I need more? What if I have to stay out longer than expected?

I want a way to get more safe drinking water when I’m out on a hike if I need it.

To accomplish this, we need to do some research and planning at home, and we need to carry the appropriate gear.

Research at Home

Before I head out on a hike, I’m doing research at home about the hike and getting a good sense of the landscape as a whole and where the water sources are.

For example: Am I hiking up to a lake that has water year-round? Will I cross a stream or river at any point? Does the trail parallel a river?

If I’m hiking up to a lake, I know that I will be able to get more drinking water with my filter if I need it. So having this info in your head beforehand is important.

There might be hikes where you don’t have access to water.

In the desert, that happens a lot. Even still, it’s important info to know because then you can access the risk of what you’re doing and perhaps pack even more water on the hike.

Water filters or purifiers

Now you know where the water sources are, so we need the proper gear in order to get more safe drinking water out on the trail.

I’ve found that most day hikers don’t carry any sort of water purification or water filtration system with them. The mentality is: “I’m just going on a day hike I can carry the amount of water that I need.”

And yes, while that may be true, it’s still important to carry a water filter on your day hikes.

Regardless of the length of the hike, I’m always packing my Sawyer Squeeze water filter.

Sawyer Squeeze water filter for hiking

I’ve been using this filter for years and I love it. It’s lightweight, small, and has a great flow rate. It’s very easy to use and take care of too. This allows me to filter water from the lake or stream that I’m hiking by and get more water if needed.

It’s also nice because if I’m on a really hot hike, I can get cold water from a stream that’s so refreshing compared to the room temp water in my backpack.

There are many water filter options on the market, so do some research to find the best fit for you.

“Two is one, one is none”

There’s an old adage: “two is one, one is none” when it comes to your life-saving gear.

In other words, you want backups.

What if the water filter that I’m totally dependent on fails me? What if I lose it? What if I drop it and it breaks?

For backup, I personally choose to carry water purification tablets.

box of water purification tablets

I would much rather use my filter, and luckily I’ve never had to use the tablets, but they are there just in case.

Also, when I’m hiking with Nick, he also always carries a water filter, so within our group of two, we have more than one filter.

A water filter is something that you should encourage everyone in your group to carry.

Taking care of your gear

Whatever you choose to use for water purification or filtration, you must make sure that you take the time to read the instructions and make sure you understand how to use it, how to take care of it, and how to store it properly BEFORE your hike.

I’ve said this so many times, but it bears repeating – you don’t want to buy a new piece of gear and take it on a hike and try to figure out how to use it when you’re out on the trail and need it.

For example, the Sawyer water filter I mentioned above should never freeze. If it freezes, you’ll need to replace it.

It’s also good practice to make sure you’re gear is working properly before a trip.

Knowing the ins and outs of your gear is important.

Day hiking in Montana


The last thing I want to talk about is electrolytes. Staying hydrated is more than just drinking water.

As you hike and sweat, your body is losing water and electrolytes. In order to stay hydrated, you need to replenish both.

Potassium, sodium, magnesium, and chloride are major electrolytes that need to be replenished.

Your body’s cells use electrolytes to carry electrical impulses that help your cells communicate.

I’ll carry electrolyte packets and a small collapsible water bottle to mix them into when I’m on the trail.

orange HydraPak collapsible water bottle

I love having a small water bottle since I don’t want all the water in my water bladder to have electrolytes.

I’ve noticed that drinking electrolytes make a huge difference for me. I feel so much better and more energized on the trail after I drink a packet.

Below are some of my favorite options:

  1. LMNT (Elemental Labs) – these are my favorite, but be warned – they are salty AF
  2. Nuun tablets – these are the classic choice! They come in tablet form and are pretty mild-tasting.
  3. MTN OPS straight-to-mouth sticks – I love the convenience of these. They don’t need to be mixed with water.

Self Awareness

Now you’re ready to hit the trails with water and the ability to get more on the trail so you can stay hydrated!

This is so important, so make sure to share this blog post with your hiking buddies so everyone in the group can be prepared.

Make sure you take care of yourself and that you remain self-aware and proactive when it comes to your health and hydration out on the trail.

You are responsible for yourself, and if you’re with a group, speak up if you need a break.

Start your hike well-fed and hydrated. If you have any other questions about water for day hikers, please comment below!

Leave a Reply

Your email address will not be published. Required fields are marked *

One Comment