Carefully managing your water supply on a long hike can be a real chore. But you can’t tackle long distances if you’re dehydrated. Thus, on an extremely strenuous hike like the Grand Canyon, water becomes a critically important topic.

In my prior post discussing the best time of year for a rim-to-rim hike, I briefly touched upon water sources inside the Grand Canyon. This post will go into much greater detail on this subject, including:

• The amount of water most hikers need throughout a rim-to-rim hike
• Locations where can hikers can resupply inside the Grand Canyon
• Which sources run year-round and which ones are seasonal
• Backup plans if the National Park Service is unable to turn on the seasonal water points inside the Canyon

An in-depth understanding these topics is essential to ensuring you have a safe and successful hike.

Why water is so important

Hiking in Arizona’s arid climate, you quickly come to appreciate what a precious commodity water is in the desert. The sweat evaporates off your skin before you even realize your body is sweating to cool itself down. The sun bakes overhead, and your eyes instinctively start searching for liquid everywhere.

Few of us start out carrying with all our hydration needs at the start of a nearly 24-mile long rim-to-rim hike of the Grand Canyon. After all, water is incredible heavy, weighing in at approximately 2.2 pounds per liter.

If you’re planning to combat dehydration by consuming a liter of water every 3-4 miles of your hike, you’d have to carry over 17-20 pounds of water on a one-way crossing. That’s a lot of extra weight to add during such a physically grueling hike!

What’s more, during the warmer months, the National Park Service warns that your water and electrolyte needs can actually exceed 2 liters per hour while you’re hiking uphill in direct sunlight. This could easily increase your pack weight even more!

So it’s no surprise most hikers want to find ways to lighten their load. Resupplying along the route is one way to do this. However, to be successful, it’s critical to know exactly where your extra water sources are located so you can monitor your consumption, manage your resupply options, and plan for contingencies.

Finding potable water inside the Grand Canyon

Potable water is defined as water that’s safe for drinking and food preparation. This is the water you expect to come out of your water tap, drinking fountains, or other treated sources. This doesn’t mean it will be the best tasting water, but it will be safe for consumption.

Before discussing where you’re likely to find potable water on the trail, you’ll need pinpoint where you intend to hike. The two routes most rim-to-rim hikers take when traversing the Grand Canyon are the most direct ones:

• The Bright Angel Trail combined with the North Kaibab Trail; or
• The South Kaibab Trail combined with the North Kaibab Trail

I discuss all the pros and cons of the hiking each of these routes in my post HERE. But for now, the main thing you need to know is that the Bright Angel Trail has multiple potential water sources between the South Rim and the Colorado River, while the South Kaibab Trail has none.

Below is a side view of these rim-to-rim routes. The North Rim is depicted on the left, and the two trails leading to the South Rim are depicted on the right.

Year-round water sources

Let’s begin with the water sources you can depend upon no matter what time of year you take on this adventure. There are a total three (3) year-round water sources available inside the Grand Canyon:

• Bright Angel Campground
• Phantom Ranch
• Indian Garden Campground

Although it’s not depicted on the diagram above, Phantom Ranch rests only about ¼ mile up the North Kaibab Trail from the Bright Angel Campground. Thus, these two year-round sources are probably best treated as a single redundant source at the bottom of the canyon.

The only other year-round water source is at Indian Garden Campground, which is located halfway down the Bright Angel Trail. This is one reason the Bright Angel Trail is so popular with hikers.

However, it’s not all that uncommon for rim-to-rim hikers to descend from the South Rim in the early morning and reach the bottom of the Grand Canyon without refilling their water even once along the way.

This is possible for a few reasons. Walking downhill the entire way (usually in cooler temperatures) means you’re consuming less water during this leg of the journey. Most hikers are also properly hydrated prior to starting their rim-to-rim hike. So, it isn’t too difficult to carry the 2-3 liters needed to safely hike the distance down to Phantom Ranch without stopping.

As a result, some northbound (or NoBo) rim-to-rim hikers deliberately to use the shorter 6.8-mile South Kaibab Trail down to the Colorado River, even though it doesn’t have any available water sources like the Bright Angel Trail.

The return hike back up to the South Rim is a far different experience though. Most southbound (or SoBo) rim-to-rim hikers find they need significantly more water than expected while climbing up toward the South Rim.

This increased thirst during an ascent can be a result of the warmer daytime temperatures inside the canyon, your body’s physical fatigue during the second half of your rim-to-rim hike, and the significant elevation change during the last few miles below the rim.

Most rim-to-rim hikers will need at least 4 liters to safely hike up to the South Rim from the Colorado River. Thus, it’s considered much safer to use the Bright Angel Trail during your ascent because it has one year-round and two seasonal water sources to keep you hydrated.

Seasonal water sources

Now that you know where the year-round sources are located, let’s discuss the five (5) seasonal water sources inside the Grand Canyon. They are located at:

• 1 ½ Mile Resthouse
• 3 Mile Resthouse
• Cottonwood Campground
• Roaring Springs
• Supai Tunnel

Bright Angel Trail

The first two of these seasonal sources are on the Bright Angel Trail just below the North Rim. As their names indicate, they’re approximately 1 ½ miles and 3 miles down in the canyon from the Bright Angel Trailhead.

Both of these water points are adjacent to bathrooms and outdoor structures where you can take a rest from the sun. Since the resthouses are located closer to the Grand Canyon Village, they can become crowded though. This is especially true in the middle of the day when temperatures rise dramatically inside the canyon.

North Kaibab Trail

The remaining three seasonal water sources are along the North Kaibab Trail. Although this trail is 14 miles long, all its seasonal water sources lie within the 7 miles closest to the North Rim. So if you’re a NoBo hiker, your first chance to refill your water on the North Kaibab Trail won’t be until seven miles after Phantom Ranch.

This stretch of the North Kaibab Trail can be quite difficult mentally and physically, even though the elevation change is minimal. First, the trail runs through the infamous box of inner canyons. Most hikers try to rush through this section because of their dangerously high temperature between 10 am and 3 pm.

Once you get through ‘The Box,’ you’ll find yourself trekking through five more miles of flat, shadeless Sonoran desert before reaching the first seasonal water source at Cottonwood Campground.

After departing Cottonwood Campground (~17 miles into your NoBo rim-to-rim hike), there are two more seasonal water points before you reach the North Rim. These are Roaring Springs and Supai Tunnel.

Roaring Springs is only two miles beyond Cottonwood Campground and requires a short detour off-trail to a small picnic area. Consequently, many hikers choose to continue on to Supai Tunnel without stopping.

Bypassing Roaring Springs could be a risky choice though. After all, the North Rim of the Grand Canyon lies 1,000 feet higher than the South Rim. And the 4,200-foot vertical gain from Cottonwood Campground to the North Rim will sap every last bit of your energy.

The final seasonal source is at Supai Tunnel, which will be nearly 22 miles into your NoBo rim-to-rim hike (and just 1.7 miles below the North Rim finish line). Topping off your water here is strongly encouraged, as North Kaibab Trail has an average slope of 13% during the last two miles below the trailhead.

Of course, if you’re starting at the North Rim and hiking SoBo, you’ll encounter all these water sources on the North Kaibab Trail in reverse. In that case it’s easier to think of them in terms of your 2-mile mark (Supai Tunnel), 5-mile mark (Roaring Springs), and 7-mile mark (Cottonwood Campground) of your rim-to-rim hike.

Of these potential resupply points, Cottonwood Campground is a critical place for SoBo rim-to-rim hikers to top off their water, as the next source is seven more miles away at Phantom Ranch.

When are these water sources available?

The National Park Service usually turns on the seasonal water from May 15th to October 15th. Thus, it’s common for hikers to use these May/October dates as benchmarks when planning their rim-to-rim hike.

However, there is no guarantee everything will actually be turned on when planned. The pipes running to these seasonal sources are decades old and in frequent need of repair or replacement. Freezing temperatures could also cause the National Park Service turn the water off earlier than planned.

In March 2017 (two months before my own R2R2R hike), a rock slide below the North Rim destroyed some of the water pipes. Repair crews closed the trail for 5+ weeks to repair the damage and get everything back up and running to Cottonwood Campground and Roaring Springs.

The trail re-opened in May. Nonetheless, the Park Rangers warned us it was still ‘hit or miss’ on whether we’d have water along the North Kaibab Trail due to the ongoing pipe repairs.

Important Tip: Always check with the Park Rangers at the Backcountry Information Center to get the most up-to-date info about the water sources inside the Grand Canyon. These Rangers can provide you with current trail conditions and the status of when water sources will be shut off – whether its for routine maintenance, unexpected repairs, or freezing temperatures.

Other backcountry sources

While it’s fine to plan around these potable water sources, this isn’t a fool-proof strategy. All rim-to-rim hikers need a back-up plan too.

Your body is 60% water, and it needs constant replenishment. This is especially true when taking on demanding physical activities or being exposed to the sun for extended periods of time.

The water sources discussed above aren’t the options along the trail. There’s also the opportunity to collect water from the Colorado River, creeks, or even potholes after monsoon rains. However, these natural water sources could contain waterborne bacteria, so all collected water must be treated before drinking to ensure you don’t get sick.

If some (or all) of your pre-planned water sources are unavailable, you can treat any collected water with a water filter, iodine tablets, or even boiling it. This will make it safe for consumption.

During my own R2R2R hike, I carried my Sawyer Squeeze Water Filter the entire way. Although I didn’t end up needing it, there’s incredible peace of mind in knowing I could survive in an emergency situation. And it was definitely worth the extra 3 ounces it weighed!

How much water will you actually need?

So, finally, we get to the big question you’ve been waiting for me to answer. How much water does the average hiker actually need during a rim-to-rim hike?

Well, it depends… There’s so many variables to consider.

What time of year will you be hiking? How hot will it be inside the canyon? Do you know how much fluid you normally consume during a physically demanding hike? How much do you sweat? Do you plan to hike rim-to-rim in one day? Or will you be hiking it over multiple days? How much gear are you carrying on your back?

Based on my own experience hiking in May 2017, I’d estimate that most rim-to-rim hikers should expect to drink at least 6-8 liters from one rim to the other – if they are doing it in a single day and with a very light load.

Of course, this isn’t a magic number. Water consumption can vary quite a bit between hikers. So, this estimate may could be on the low side if you’re someone who needs to drink a lot on the trail to remain hydrated.

Also, it’s important to remember that water alone is not sufficient in the Grand Canyon. As you sweat from the physical exertion of this rigorous hike, you will be losing a lot of electrolytes. Replenishing them with sport drinks and/or salt is critical to avoiding dehydration and heat injuries.

Interested in more information about planning a rim-to-rim hike of the Grand Canyon?

Check out the upcoming blog posts on:

• Deciding Whether to Hike the Grand Canyon in 1 Day, 2 Days or More
• Gear Every Rim-to-Rim Hiker Should Consider Taking
• How to Fuel Your Body to During Your Rim-to-Rim Hike

The material provided in this blog is informational only. Hiking in the Grand Canyon is an inherently risky activity. Every hiker is responsible for their own health and safety, and should plan for their rim-to-rim hike with those risks in mind. Outdoor Pilgrim is in no way responsible for the use or misuse of this information. Please hike responsibly!