Wilderness Safety

There are many rewards and benefits associated with visiting wilderness. However, wilderness travel involves an element of risk. Learn more about personal safety and responsibility...[Photo]: Roaring falls over rock streambed.


"When all the dangerous cliffs are fenced off, all the trees that might fall on people are cut down, all of the insects that bite are poisoned...all of the grizzlies are dead because they are occasionally dangerous, the wilderness will not be made safe. Rather, the safety will have destroyed the wilderness."

- R. Yorke Edwards (Canadian environmentalist)


Stream Crossings | Lightning | Hypothermia

Altitude Sickness | Avalanches | Weather

Purifying Water | Emergencies


Don't underestimate the power of swift water - it can be deadly. Look for a natural bridge such as logs or rocks to cross, but be careful - they can be extremely slippery. If none are available, wade the creek or stream where it is wide and shallow. Make sure your crossing is not above rapids or a river gorge in case you fall into the current. Unbuckle the waist strap or hipbelt of your pack and use trekking poles or a long stick for stability. It is safer to wear shoes while crossing water. If you are with a group, cross together while holding onto each other; never tie yourselves into ropes. Cross in early morning when water level is lowest.


Watch for approaching storms and go to a safe area before they arrive. During lightning storms avoid mountaintops or ridges, open areas, a lone tree, shallow caves, and the base or edge of cliffs. Forested areas away from the tallest trees are safer.

If you are in a treeless area and cannot get to a safer place, put insulating material (poncho or foam pad) on a small rock and sit on it - only your buttocks and feet should touch the material. Clasp your hands around your knees. This method should be used only if there are no alternatives.


Be aware of the danger of hypothermia, which occurs when body temperature become subnormal, potentially leading to mental collapse and even death. Hypothermia is caused by combinations of cold, wetness and wind, and is aggravated by exhaustion. Most hypothermia cases develop in air temperatures between 30 and 50 degrees Fahrenheit, but it can happen during any season. Stay dry, because when clothes get wet, they lose almost all of their insulating value - wool and synthetics provide better insulation when wet than cotton and down products.

Signs of hypothermia are uncontrollable shivering; vague, slow, slurred speech; memory lapses and incoherence; stumbling, drowsiness, and exhaustion. The victim may deny any problem - believe the signs, not the victim. Even mild hypothermia demands immediate treatment.

Shelter hypothermia victims from wind and rain; give warm drinks; get them into warms clothes and a sleeping bag and keep them awake.


Plan your trip to allow time for a slow ascent with gradual adjustment to altitude. Altitude illness can strike anyone - young or old, fit or unfit; too little sleep, dehydration, malnourishment, alcohol and/or drugs may make things worse. Typically, serious altitude illness occurs at altitudes over 10,000 feet, but in the Sierra there have been serious cases starting at over 8,000 feet.

Awakening during periods of normal sleep with temporary shortness of breath or gasping for breath is common. The higher the altitude, the more common this syndrome becomes - this syndrome alone is normally no cause for alarm.

Acute mountain sickness is usually a mild illness consisting of a headache, nausea, difficulty sleeping and fatigue. When acute mountain sickness becomes severe, two life-threatening illnesses may result:

  1. High Altitude Pulmonary Edema (HAPE)
    HAPE has the following signs: extreme shortness of breath; the need to sit up to breath; extreme fatigue; mild wheezing or sudden onset of cough; and the inability to sleep. The most obvious sign is a bubbling or gurgling sound from the chest, audible without the use of medical instruments. Victims experiencing HAPE should immediately retreat to lower elevation and seek medical help, as the condition can lead to death.
  2. High Altitude Cerebral Edema (HACE)
    HACE symptoms include a very severe headache, vomiting, confusion and loss of balance or coordination. Immediate descent to lower altitude is the only treatment and cure. Get immediate help; the condition can progress rapidly and death may result. The victim may be walked slowly to low altitude if his/her condition is not too severe. Very weak victims should be carried to a lower elevation. If your party is unable to evacuate a victim, find a ranger who can call for additional assistance by radio.


While the Sierra Nevada has a reputation for mild winters and low avalanche danger, avalanches do occur and can be deadly. Become familiar with danger signs, potential avalanche terrain, and be sure to check weather and avalanche reports prior to entering the wilderness, More...

WEATHER  www.forecast.weather.gov

Winter generally begins mid-November when autumn precipitation refuses to melt away, though winter conditions may begin as early as September or as late as January. Temperatures are generally mild and typically range from 0-40 degrees Fahrenheit.

Spring begins in April and lasts through June, providing great spring skiing and opportunities for solitude for those willing to travel over snow and ice. Early season hikers and climbers should be prepared for winter conditions, icy passes, and significant stream flows. Check weather forecast, severe snow and wind storms can still occur.

Summer brings comfortable temperatures between 30 and 70 degrees Fahrenheit, though at high altitude the sun can certainly feel hotter. Protect yourself against sunburn and early season mosquitoes, generally prevalent in July and early August. Afternoon thunderstorms are quite common during the summer months and visitors should carry rain jackets and storm protection. See lightning for more information.

Autumn can be one of the most pleasant seasons in the Sierra, though the threat of an early winter should be taken seriously. Storms can drop snow that either melts quickly away or brings the coming winter season. Cold nights and warm days are typical. Visitors can experience a greater sense of solitude during the autumn season.


An intestinal disorder called giardiasis (gee-ar-dye-a-sis), as well as others, may be contracted from drinking untreated "natural" water. This disorder is caused by a microscopic organism, Giardia lambia, the cystic form of which is often found in mountain streams and lakes. Such water may look, smell and taste good, but you should be aware of possible danger. Many cases of giardiasis have been attributed to untreated water in the Sierra Nevada.

Although giardiasis can be incapacitating, it is not usually life threatening. Symptoms usually include diarrhea, severe gas and bloating, loss of appetite, abdominal cramps, and weight loss. These signs may appear a few days to a few weeks after ingestion of Giardia and may last up to 6 weeks. Treatment should be sought and generally includes powerful doses of antibiotics.

Three ways to treat water are to boil it, treat it with iodine based chemicals, or use a filter or purifier:

  1. Boiling: Bringing water to a momentary full boil is enough to kill Giardia, though boiling for at least 5 minutes is recommended. Plan to bring extra fuel as boiling at high altitudes takes more time and energy.
  2. Iodine: Iodine tablets or drops are lightweight and simple to use. Iodine tablets do kill Giardia, but take at least 30 minutes to work and leave an iodine flavor that can be counteracted to some degree by complimentary pH tablets. Be sure to read all warnings on product labels.
  3. Filter: Using a 2-micron filter will effectively filter out Giardia and other particulates; smaller sizes (and purifiers) can be used to filter out other dangers as well. Filtering water is relatively quick and leaves no taste in drinking water, however you should be familiar with your filter and carry a replacement cartridge or know how to maintain a ceramic filter.


When you travel into wilderness, plan to be self reliant. There is little to no cell reception in most of the forest. If you do request a rescue, be aware that help may be several days out. Air evacuation may be delayed by high wind or rough terrain. Leave detailed travel plans with someone you trust to initiate a rescue if you are overdue. If you are lost or unable to self rescue, stay in one place, preferably in an open area visible from the air.

Search and rescue teams are all volunteers in this area. Rescue should only be requested in true emergencies. To initiate a rescue, contact the local Sheriff's Office with the following information: Nature of the emergency, include who, what, where and when, and the current location of the person needing assistance, if the location is unknown it may be helpful to provide a description of the vehicle and travel plan.

Contact numbers:

Mono County Sheriff (760) 935-4066

Inyo County Sheriff- Search and Rescue

  • Bishop (760) 873-7887
  • Independence (760) 878-0383
  • Lone Pine (760) 876-5606
  • Olancha  (760) 852-4313