Last updated: August 7, 2020
Rivers and streams can be a refreshing way to experience national parks. You can swim, boat, fish and so much more!
On the surface, rivers and streams can seem calm, warm or shallow. Yet every year even the most experienced park visitors become victims to deceptively strong currents, cold water temperatures, and unexpected changes in depth. Whether you’re floating down a lazy river, fishing, or cooling off from a long day's hike, it is important to understand water safety in and around these tempting waters.
Use the NPS Trip Planning Guide and Checklist to help plan your trip.
The NPS Trip Planning Guide provides key safety considerations to help you avoid some of the most common mistakes people make when visiting national parks. Learn about the park’s environment, pick the right activity for your skill and experience level, and pack the right gear and equipment for your activity.
Find out which water activities are allowed
Visit the park’s website to learn which water activities are available. Take note of park recommendations for specific recreation sites. For example, swimming may not be recommended or may even be prohibited because of the hazards in the water.
Get Required Permits
Find out if you need a permit for your activity and make sure you have all the required documents before you head out.
Check water and weather conditions
Visit the park’s website to learn about water and weather conditions before you head out. Information may also be found at visitor centers and ranger stations once you get to the park.
Unseen Water Hazards
Rivers and streams can appear calm on the surface but there may be:
Strong undercurrents that can pull under even a strong and experienced swimmer
Strainers (branches that act like a sieve and keeps people/ boats/ gear from passing through) and blockages such as trees, debris, etc. that can cause you to become trapped underwater or pinned against the object
Narrow gaps between rocks that can trap you under water
A slippery and uneven bottom that can make it easy to lose your footing
Unstable riverbank, especially during and after floods and heavy rain.
Cold Water Temperature
Even on a nice sunny day, the water temperature can be extremely cold below the surface. Hypothermia can quickly set in and overwhelm even the strongest of swimmers. Hypothermia occurs when your body loses heat faster than it is produced and is no longer able to warm itself. Learn more about how to prevent, recognize, and respond to cold related illness.
Water moving in a river or stream is called a current.
Currents can be powerful even if the top of the water looks calm.
In as little as six inches of water, there can be currents strong enough to knock you off your feet and sweep you downstream.
In summer, water levels can rise quickly and without notice from heavy rain or snow melting in nearby mountains.
Do not underestimate the power of currents and overestimate your swimming abilities.
Kayaker in white and green water
Know the different types of currents and understand where they will take you if you plan to recreate in, on, or around rivers and streams. The water may look calm on the surface but strong currents lie underneath. Water levels change currents. Low levels reduce the flow of water leading to slower currents. High levels, like those that occur after snow melt or during flooding, can turn a calm river or stream into raging water rapids.
Some rivers have whitewater. Whitewater is caused when river currents bounce off boulders to form frothy waves. Whitewater can be lots of fun in a raft or boat. It also means business, so you should have the skills to safely navigate rapids before attempting whitewater sections of a river. There is an international standard of whitewater difficulty that most river rapids are rated by:
Class I – Fast moving water with riffles and small waves. There are few or no obstacles, which can be easily maneuvered around.
Class II (Novice) - Easy rapids with wide, clear channels and small waves. Some maneuvering may be required.
Class III (Intermediate) - Rapids with high, irregular waves. Tight passages and obstacles require complex maneuvers in fast current. Scouting (looking at a rapid before paddling) is advised for inexperienced parties. Selecting the right vessel is necessary to be able to navigate the rapids.
Class IV (Advanced) - Intense, powerful but predictable rapids. Complex maneuvering is often required in constricted passages and turbulent water. Rapids may require “must” moves above dangerous hazards. Scouting is often necessary.
Class V (Expert) - Extremely difficult, obstructed or very violent rapids. Rapids may continue for long distances down congested chutes with complex and demanding routes, which expose a paddler to added risk. Scouting should happen from shore but may be difficult. There is a significant hazard to life in the event of mishap, and rescue opportunities are usually challenging. Class V is the upper limit of what is possible in a commercial raft.
Use the international standard levels for rapids to help you choose the best experience for you and your group including selecting the:
Right difficulty level based on your skill, experience, and fitness
Proper vessel for the river you will be traveling on (e.g. canoe, kayak, raft)
Gear and equipment for you and your vessel (e.g. life jackets, radios, floatation bags, helmets, etc.)
Read on for more information on some specific safety considerations based on the activities below:
Many trails in National Parks run along rivers and streams
If you are hiking:
Always stay on the established trails or developed areas. Maintain 6ft distance away from the water.
Keep a close watch on children even if they are far from the water. Supervision of children is especially important as they can quickly enter the water and get in trouble when your attention is diverted, even if only for a moment.
Do not walk, play, or climb on rocks and logs near rivers and streams. Water polishes rocks along the water's edge making them slippery when wet or dry.
Do not cross above rapids or falls. You can be swept off your feet and go over the falls. Look for another place to cross where the water is shallow and calm.
Unbuckle your pack's waist strap when crossing a river or stream. This will make it easy to take off the pack if you fall and prevent you from being pulled under by its weight. Consider putting your pack in a waterproof backpack, which can become a floating device to help your head stay above water. Lake Clark National Park & Preserve has additional information on river crossings.
Always wear a life jacket when on, in, or around water
If you are fishing, swimming, or wading:
Wear a properly fitting life jacket. Don’t assume you have the swimming skills to keep you afloat in the water. Even the strongest swimmers can drown.
Do not fish, swim, or wade upstream from a waterfall. You can be quickly swept off your feet and go over the falls even if the water appears shallow or calm.
Learn more about swimming and fishing in national parks.
Close-up of rafters in whitewater
If you are in a vessel:
Learn more about how to be prepare yourself and your vessel for boating before you go, how to have a fun and safe trip on the water during your visit , and what to do if someone goes overboard.
If you have a water related emergency:
- Call 9-1-1 for help. Time is of the essence. Be ready to tell the 9-1-1 operator the circumstances of your emergency (e.g. where you are located, the number of people impacted, etc.) A distress call can also be made on Channel 16 of the marine VHF radio.
- DO NOT attempt a rescue by jumping into the water. Many people have drowned while trying to save someone. Only a person who is trained in water rescue should enter the water to rescue someone in trouble
The National Park Service provides different recreational and scenic opportunities on rivers across the country. Learn more about where these rivers can be found.