Choosing a campsite: flash floods, dead branches, wind and rockfall

Where you pitch your tent decides most of how safe your night will be. A flat gravel bar by a creek looks perfect at sunset; with rain upstream it can be part of the creek by midnight. This guide pulls together what the National Park Service, NOAA and Japan's river authorities say about choosing a site, plus the knots and habits that make pitching and striking camp go well.

Start with the rules

Camp where camping is allowed: a designated site in a campground, or where backcountry rules permit it. The NPS's version of the Leave No Trace principles says "Good campsites are found, not made," lists "maintained trails and designated campsites, rock, gravel, sand, dry grasses or snow" as durable surfaces, and asks you to protect streamside areas "by camping at least 200 feet from lakes and streams." Individual parks add their own rules, so check before you go.

Hazard 1: water that isn't there yet

Flash floods are the classic campsite killer because the storm can be somewhere else entirely.

• Grand Canyon: "Hikers have been killed in flash floods generated by thunderstorms as far as 25 miles away." "Never camp in a dry wash."
• Death Valley: "Do not camp in dry washes or drainages due to potential flash flood danger."
• NOAA: "Do not camp or park your vehicle along streams and washes, particularly during threatening conditions. Be especially cautious at night when it is harder to recognize flood dangers."
• The National Weather Service: "it doesn't have to rain directly over you for there to be flooding. If you notice even a slight rise in water level, seek higher ground immediately!"

If you must camp near a wash, Grand Canyon advises camping "as high as possible" and checking "for indications of past high water, such as stains on rock walls and debris lines."

Japan has a well-known example. On August 13–14, 1999, campers were on a sandbar in the Kurokura River in Kanagawa Prefecture when heavy rain set in. According to Japan's river ministry, most campers in the area left, but a group of 18 stayed despite repeated warnings. By the next morning the water was about 85 cm (nearly 3 feet) above normal and the group was stranded on the bar; 5 survived and 13 died. Japan's river offices now warn that a sandbar is "the river itself," even if grass grows on it, and that bare, unvegetated ground along a river is a sign that water runs there when it rises.

Hazard 2: what's above you

The NPS camping page is blunt: "Look up; if you see dead branches overhead, you should not camp under them." It also says to camp "Away from dead trees that might fall." Scouting America puts it this way: "Avoid campsites with hazard trees. Dead trees and dead limbs may fall at any time." And branches don't need a storm: one NPS park warns that "Branches and trees may fall whether or not they are dead, and when there is no wind," and advises looking for "dead, cracked, broken, or hanging branches" before choosing a place to camp.

Grand Canyon adds rockfall: "Watch and listen for rock falls and slides, especially during and after downpours. Do not stand at places where rocks have obviously fallen before." Fresh rocks at the foot of a slope are a reason to move.

Hazard 3: wind and lightning

NPS advice is to camp "Sheltered and away from the middle of a field if there is a lightning storm and from the edge of cliffs," and in the backcountry to "avoid staying on ledges or high peaks where wind and lightning could become a hazard." A line of trees or a low rise upwind can make a big difference to a tent (our view); just make sure those trees pass the "look up" test. For what to do when thunder rolls, see lightning safety outdoors.

A five-direction check (our suggestion)

And check the forecast for the whole watershed upstream, not just your site.

Pitching: three knots worth knowing

Scouting America's Cub Scout tent activity says to "Use taut line hitches to tie the free ends of guylines around stakes you've pushed into the ground and pull the lines tight." Its troop leader resources describe the bowline as forming "a fixed loop at the end of a line" and say "The clove hitch is used to secure a line to a pole." Between them you can tie a tarp to a tree (bowline or clove hitch) and tension it to a stake (taut-line hitch). Learn them with a person or a photo guide; knots are hard to learn from words alone.

Our suggested order: arrive in daylight, clear stones and sticks, put your head slightly uphill, face the door away from the wind, then pitch, stake and guy out every line before dark. Check the lines again before bed.

Striking camp: dry it before you store it

Packing up wet is often unavoidable; storing a tent wet is not. Sea to Summit's care guide says to separate the inner tent and rainfly "and hang them up until they are completely dry," and warns that "If a tent smells musty when you go to use it, it has begun to develop mildew." Japanese maker Montbell adds the opposite caution: don't leave a tent hanging in the sun for long periods, because UV significantly weakens the waterproof coating.

After a disaster

If you ever pitch a tent in a yard or park after a storm or earthquake, the same five-direction check applies, with new hazards above and behind: downed or sagging power lines, cracked trees, damaged walls (our view). Never run a stove, heater or generator in or near the tent; see carbon monoxide at camp. To practice a night on camping gear at home first, see disaster camping.

Our Japanese edition has a separate article on the same subject, focused on Japanese rivers and campsites: テントを張る場所の選び方と設営・撤収.