Warning: Hiking in Colorado subjects you to volatile and dangerous weather, difficult terrain, and risks of rockfall and avalanche, among other things. Hikers die every year due to being unprepared.
Avalanches
In the winter and spring, there is a risk of avalanche, even on established hiking trails. A good example of a dangerous trail that is very popular would be the Grays Peak Trail, which hundreds of people use on a given day during the summer. In the winter, this trail crosses an avalanche slope on Kelso Mountain which has led a number of people to trigger avalanche slides. [1] [2] If you are traveling into backcountry terrain (anywhere not at a ski resort), ensure that you understand the risks of avalanche danger, check the CAIC website for snow conditions, and definitely consider taking an avalanche awareness class.
Altitude Sickness
Many people who visit Colorado and even people who live in Colorado experience altitude sickness at some point and it generally becomes a possibility once a person goes above 6000 feet in elevation. Physical fitness does not appear to impact a person's susceptibility to altitude sickness. A mild form of altitude sickness (known as Acute Mountain Sickness or AMS) is the most common issue and it can present itself as dizziness, shortness of breath, nausea, vomiting, headaches, and trouble sleeping. AMS occurs in approximately 20% of people going rapidly to 8000 feet and 40% of people going rapidly to 10000 feet.
More serious forms of altitude sickness include High Altitude Pulmonary Edema (HAPE) and High Altitude Cerebral Edema (HACE), both of which can be life-threatening. HAPE results in fluid in the lungs and manifests as a persistent cough and other symptoms similar to bronchitis. HACE results in brain swelling, which can cause a person to appear unsteady or intoxicated, a severe headache, severe nausea and vomiting, retinal hemorrhaging, and possibly loss of consciousness and death. When traveling to Colorado for hiking, it is generally a good idea to stay at a lower elevation for one day and night prior to embarking on a hike to higher elevations, since it will give your body a chance to adjust. Coming to Colorado and attempting to climb a high peak the same day presents a substantial risk of some kind of altitude sickness. More information on altitude sickness.
Cardiovascular Effects at Altitude
Generally, you will experience decreased cardiovascular performance at higher elevations in Colorado due to the decreased levels of oxygen in the atmosphere. At 14,000 feet there is roughly 40% less effective oxygen available for you to breathe than there is at sea level. When climbing a high peak, you will likely feel increasing shortness of breath the higher you go in elevation since the oxygen levels decrease and your body struggles to get the oxygen it needs to fuel your activity. This drop in oxygen can cause a hike to take much longer than originally anticipated since you will be moving slower. It is a good idea to pace yourself and take breaks as needed to hydrate, snack, and catch your breath. When going uphill it can often take an hour for most people to go 1-2000 vertical feet.
Group Mentality and Summit Fever
In hiking groups or popular hiking trails, people often feel like they are safe in dangerous conditions just because they are with other people doing the same hike or they see other people continue to go up the 14er, even as lightning strikes around them. It is important to identify when to turn around and trust your own instincts. A lot of the hikers in Colorado are tourists who may not understand the dangers associated with lightning, storms, etc. and they will continue to attempt a summit even if there is a storm rolling in. Sometimes you may follow someone assuming they know where they are going only to find out that they have no idea or they are headed somewhere else entirely. Many hikers also feel "summit fever" where they are reluctant to turn around after committing so much effort to getting to the trailhead, hiking so close to the summit, etc. That summit isn't worth dying over and it will be there another day!
Hypothermia
Many unprepared hikers dress only for sunny conditions and some do not realize the significant difference between temperatures in Denver and temperatures at 14000 feet. It might be 90 degrees F in Denver and sub-freezing on Mount Evans with 60 mph wind gusts. Hypothermia is a common issue in Colorado due to hikers not checking the weather and not taking appropriate layers, such as insulating layers and storm shells. If it rains and becomes windy, cotton jeans can become very cold and leave you shivering.
Lightning
One of the major environmental risks in Colorado is lightning. Many hikers have horror stories of their hair standing on end or their trekking poles buzzing after a storm cloud moves in. Lightning storms can move in quickly, especially in the summer months, as clouds form in the morning and move across the state. If you see a storm cloud heading your way, you should plan to head for treeline and/or the trailhead. On mountains, it can be hard to see incoming storms, especially if you are on an east face. You might reach the summit and see a storm that is minutes away. Lightning can strike up to 10 miles away from a storm. If the sky is clear for you, but you can see a storm at a nearby peak, you're still in danger. It is always a good rule to start early and be prepared to turn around if a lightning storm moves in.
Rockfall and Unstable Terrain
The Rockies are called that for a reason. In Colorado, there are a lot of mountains covered with loose rock and boulders, as well as smaller rocks. Large rocks are sometimes unstable and stepping on them can cause them to roll over onto you (this killed one of my former coworkers on a 14er) or roll down the mountain and hit someone. Even a small rock can quickly pick up speed and hurt someone if the mountain is steep enough. If you are using rocks for handholds, they can come loose and cause you to lose your balance or fall. Finally, many trails in Colorado are covered in small loose rocks called scree, which can make it hard to get solid footing and can slide out from under you. A steep descent down a scree slope can be an unpleasant end to a hike when you are tired and just want to get back to the trailhead.
Snow and Ice
One thing that often surprises people visiting Colorado is that the mountains have deep snowfields that can persist well into the summer and often cover popular hiking trails. What that means is that if you come in the spring or summer (April, May, June, July, and even into August) you may encounter conditions that require you to wear snowshoes or traction devices to avoid postholing (your leg punching into deep snow) or slipping on snow and ice. Microspikes and similar products are a great option for a lightweight traction control that fits over your boots and can easily be put on and removed when snowfields are encountered on a hike. Other helpful gear to have includes trekking poles (similar to ski poles) and even ice axes for steep snowfields. Before using an ice axe or traversing, ascending, or descending snowfields, it is a good idea to learn self-arrest techniques since a fall could mean a long slide or tumble that can result in injury or death. Even with proper gear and training, it is still possible for a person to slip and fall without being able to self-arrest.
Sunburn and Snow Blindness
At high elevations, you are getting bombarded with a lot more UV and other radiation than you would be at sea level or in Denver. Sunburn is a significant concern in Colorado year-round. Another risk from the sun is snow blindness, which is a sunburn of the eyes that can leave you unable to see and in serious pain. This is most common on sunny days at elevations with a lot of snow reflecting UV radiation into your eyes. It is very important to have UV protection for your skin (clothing, hat, and/or sunblock) AND your eyes.
Weather Deterioration
Due to the high mountains in Colorado, weather conditions can change rapidly. You might have blue skies one minute and then a storm rolls in, making it so that you can no longer see more than 20 feet and no longer know where you are. This has led to many people getting lost or killed due to disorientation. The terrain in Colorado can make it hard to see storms moving toward you, since they can be hidden by the high peaks. It is important to be prepared for rapid weather changes by having appropriate clothing and gear as well as checking weather conditions for the area and elevation that you are headed to.
Important Questions on Preparation
Before you leave for the mountains, ask yourself important questions like these:
- Would you still be warm with your gear if you were caught in a storm or lost/injured and had to stay overnight?
- Would that one bottle of water keep you going if your hike takes longer than expected or you had to stay overnight?
- If you don't make it back before dark, do you have a light?
- If you don't make it back home, does someone know where you are and that they should call for help?
- If your phone or GPS battery dies, will you still know how to get back to the trailhead?
Search and Rescue
In the event that you are lost or injured in Colorado, it can take search and rescue days or weeks to find you or your corpse. Don't expect that you can take on a difficult ridge unprepared and ring up search and rescue to pick you up later in the day if it doesn't work out. To get rescued, search and rescue personnel first have to know where you are and that you need finding. They also need good weather conditions and some people have had to wait out storms for multiple days before being rescued. When people have to rescue you, they are often putting their own lives at risk and it should only be considered a last resort when self-rescue is impossible.
Personal Locator Beacons
A useful tool to have when hiking in remote areas is a personal locator beacon (PLB), which can detect your location and transmit a distress signal to satellites monitoring the entire planet. Having one of these devices can mean a difference between dying in the wilderness and getting rescued. PLBs are intended for emergency use only, so only use them when self-rescue is impossible.
Leave No Trace/Trail Etiquette
To avoid having a negative impact on the environment, wildlife, and other people while hiking and camping, it is important to practice the seven principles of Leave No Trace (LNT). Many hikers are not aware of these principles and their behavior can leave an impact that can damage our mountains for years or tens of years, such as destroying fragile alpine tundra, leaving graffiti, and starting forest fires by not properly managing camp fires. These are sort of the golden rules of the outdoors and can be found here. If you see someone violating these principles, it is a good idea to bring it to their attention or notify the authorities, since we are all part owners of our public lands.
Informational Links
Colorado Avalanche Information Center
Colorado Outdoor Search and Rescue Card
COTREX - Colorado Trail Explorer
SNOTEL - Snowpack Levels in Colorado
Local Outdoor Organizations
Colorado Fourteeners Initiative
Friends of Mt Evans and Lost Creek Wilderness
Friends of the Dillon Ranger District
Rocky Mountain Field Institute
Trails and Open Space Coalition
Volunteers for Outdoor Colorado
Wildlands Restoration Volunteers
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