How to Stay Cool on Hot River Trips

Late-summer river trips can be blissfully simple because you can get by with less gear: No need for fleece layers at night or extensive splash gear during the day. But as the average summer temperatures keep getting hotter, especially on some of the most popular western U.S. river sections, it’s smart to thoroughly prepare your river trip crew for searing temps.

Heat-related illnesses—heat stroke, heat exhaustion, or heat cramps—can become serious when medical help isn’t available, so prevention needs to be top of mind on a river trip. We’ve fine-tuned our hot-weather game plan based on our experience running stretches where daytime temps are routinely above 100 degrees, such as Desolation Canyon, Labyrinth Canyon, and Grand Canyon, among others. Here are our hard-won tips for keeping heat-related problems at bay so you can embrace and revel in those sun-baked days on the river. (Note: Some of these links are affiliate links, meaning we might make a small commission if you buy something.)

1. Bring plenty of water

Many of the permitted rivers in the western U.S. have heavy sediment, so it’s not practical to filter as much water as you’ll need for a typical scenario—for example, 16 people on a 5-day trip. When headed to a silty river in hot temps, bring drinkable water in jugs—and bring a filter as a backup. Plan on bringing about a gallon of water per person per day. (For more details on this topic, check out our post on choosing water containers and water filters.)

2. Encourage everyone to drink water

You would expect everyone to drink lots of water when it’s hot. But that doesn’t always happen. Unless you’ve brought massive quantities of canned or bottled water and have it on ice (impractical and not eco-friendly), everyone will need to embrace plain old water, which will likely be lukewarm at best. You can make it more palatable—especially for kids—by adding Nuun or some other hydration powder, which will also deliver some welcome electrolytes. On the river, make sure everyone has easy access to a water bottle (bring extras as someone will always forget theirs). Water bottles with straws like this HydroFlask are easier to use on the river as there are no lids to fumble and they’re less likely to spill. Keep a water jug accessible on one of the rafts, so when you stop for scouts or for lunch, you can easily pull out that jug and everyone can fill their bottles.

3. Stay hydrated with watery fruit

On hot river trips, we bring plenty of water-packed fruit—watermelon, grapefruit, oranges, etc. Fruit with heavy rinds hold up better on river trips than fragile fruits like berries. Top tip: Cut the fruit and pass it around—don’t ask people if they want it. If you cut the fruit and hand it to them, they will eat it and they will be more hydrated. (Especially kids, but this works with adults, too.)

4. Bring a sun shade (a tarp works)

At some point during your trip, you’ll want a way to create some shade with a simple tarp suspended by oars or a purpose-built sun shelter. Consider investing in a Bimini type of shade for rafts, especially the ones the kids are in. In sun-blasted camps, sun shelters such as the MSR Rendezvous are game-changers for providing instant relief. But a simple tarp suspended by cam straps works fine, too.

5. Sleep cool

On most western river trips, the temperature drops dramatically after the sun goes down. But if it’s too hot to sleep, you have some options. Bring a cotton sheet to throw on your sleeping bag and sleep on top of it to create some separation between you and that sticky-feeling sleeping bag fabric. Ditch your tent completely, throw your sleeping pad on the sand, and sleep out under the stars. Or rig up your sleeping pad across one of the raft thwarts and sleep on the boat, availing yourself of the cool river breeze. (Don’t put yourself in a position where you could accidentally roll off the boat into the water, and skip this idea if there’s any chance of flash floods.) 

6. Seize opportunities for water immersion

One of the most effective ways to avoid heat-related illness is to cool off in the water. In flat water, encourage everyone to jump in the water and swim around—including the people rowing rafts. Try to time lunch breaks near waterfalls or tributaries with cooler water so everyone can get a good dunking. 

7. Plan your day to minimize sun exposure during the heat of the day

Sun-soaked rivers in canyon country offer few opportunities for shade. On brutally hot days, try to launch early and get a few miles in before noon. Take a long break during midday, rig a shelter, and give everyone a break for an hour or two. Then bag a few more miles in the late afternoon when shadows are getting longer. 

8. Wear sun-protection clothing

Full-on sun-protection apparel should be the first line of defense against sun exposure, with sunscreen as a backup. The more skin you cover with light, UPF garb, the less sunscreen you’ll need and the cooler you’ll feel. Check out “Best Sun-Protection Clothing for River Trips” for our UV-protection clothing recommendations.)

9. Bring plenty of sunscreen, lip balm, and sunburn relief remedies

For river trips, mineral sunscreens are most effective, and a face stick like Sun Bum is easy to apply frequently even if you’re paddling a kayak. Bring several tubes of lip balm with sunscreen. For the inevitable cases of sunburn, bring aloe gel or another sunburn remedy.

10. Bring extra hats and sunglasses

Hats blow off, sunglasses get broken or left behind. Encourage hats with chin straps. This Sunday Afternoons hat is a great choice for kids as it includes some neck protection. This Outdoor Research hat is a variation on that theme. But any sort of hat is better than nothing, so I throw in several extra baseball hats for those who might need them. Same with sunglasses: Round up a few pairs of grocery-store sunglasses (make sure they have full UV protection) or pick up some inexpensive but good shades like the Tifosi Swank or Knockaround Paso Robles. And throw in a few Chums as well. 

11. Plan hikes carefully

Try to time side hikes early in the morning or late in the day. If you roll up to the petroglyphs that everyone has been dying to see at high noon, take care to keep the crew from overheating. Make sure everyone has water bottles available, even if you’re only going a half-mile. Encourage a round of sunscreen. If you’re headed to a cave, bring some snacks and enjoy the shade. 

12. Go light and cool on food

Extreme heat tends to sap appetites. Keep energy up with frequent breaks for light snacks: Pass around the melon, oranges, grape tomatoes, carrots, hummus, and nuts. For dinner, think about cold soups like gazpacho as an appetizer, and a cold grain salad with smoked salmon as the entree. (For river meal tips, check out “Time-Tested Guidelines for Raft Trip Meal Planning.”)  

13. Cut down on alcohol

As we all know, alcohol dehydrates. Consider chasing every alcoholic beverage with a swig of water, and think long and hard about drinking wine or hard liquor on hot desert trips. The explosion of non-alcoholic beers (Athletic Brewing’s Upside Dawn is our go-to) makes it easier for everyone to pace themselves. 

14. Watch for signs of heat-related illness

Despite your crew’s best efforts, someone might fall prey to heat stroke, heat exhaustion, sunburn, or other heat-related maladies during your river trip. Common signs of heat exhaustion include dizziness, headache, tiredness, nausea, and fainting. Remedies include moving the victim to a cooler place—find shade, rig a shelter, or get them into the water to cool off. According to the Centers for Disease Control, heat stroke (the signs include fever, confusion, and a fast/strong pulse in addition to the aforementioned symptoms) is a medical emergency. For that reason, consider bringing a SPOT or other satellite messenger device on hot desert trips. 

Safely savor a sun-drenched river trip

Long, lazy summer days on a wild river are an unmatched delight. With a few precautions and some savvy gear picks, a sun-soaked river trip can be the highlight of any river tripper’s year.

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