High-Altitude Stand Up Paddle Boarding:
Preparing for Cold Water and High Elevation
Paddle boarding on an alpine lake looks beautiful in photos, but paddling at 9,000 feet and above demands respect. High-altitude waters introduce physical and environmental challenges that can quickly turn a casual afternoon into a stressful situation if you are unprepared. To have a safe day on the water, you need to understand how the elevation affects your body, how the mountain environment impacts water temperatures, and what specific gear configurations are non-negotiable.
The Reality of High-Altitude Water Temperatures
The first thing to understand about alpine lakes is that they stay freezing cold year-round. Even in July and August, when daytime air temperatures feel perfect, the water in high-elevation lakes consists of recent snowmelt. Water temperatures rarely rise above 50 to 55 degrees Fahrenheit.
Falling into water this cold triggers an immediate physiological reaction known as cold water shock. This causes an involuntary gasp for air, which can be dangerous if your head goes under. Because of this, dressing for the water temperature, rather than the air temperature, is a critical safety rule.
- Avoid cotton entirely, as it holds moisture and strips your body heat if it gets wet (but honestly, wear what you have on your first handful of outings).
- Opt for synthetic, quick-drying layers like polyester and nylon — “sun shirts” are a great option for layering and protecting from the baking sun (I have a PFG button up and hooded sun shirt, both do their job well).
- If you plan to paddle far from shore layer for the wind, even if it isn’t windy when you leave shore (we paddle in puffy jackets + rain layers to cut the biting wind in the middle of Lake Dillon Reservoir, no joke).
- Your feet will likely get wet while you launch from shore — plan accordingly by opting for sandals or at least leaving your socks behind (I personally prefer something similar to these slides and these hiking sandals).
High Altitude Weather & Wind
At 9,000 feet, the air is thin, meaning there is less oxygen available with every breath. Stand up paddle boarding is a full-body workout that requires constant core stabilization and upper body strength. When you combine that physical exertion with high altitude, your heart rate escalates much faster than it would at sea level.
You will tire out more quickly than you expect, especially when paddling against a headwind. Pace yourself during the first 30 minutes to gauge your energy levels. And be aware of which way the wind is blowing (while also knowing it will change at anytime, especially on Lake Dillon Reservoir). If the paddle out seems easy it will likely be a rough paddle back as you’ll be paddling into the wind. This is another “ask me how I know” situation, I’ve had long, draining paddle back to shore (from poor planning and from changing wind).
Weather shifts rapidly in the high country. A blue-sky morning can transform into a lightning storm with high wind gusts in under an hour. On mountain reservoirs and lakes, wind patterns are notoriously unpredictable. The wind frequently picks up by early afternoon, creating choppy water and strong whitecaps that make paddling back to shore incredibly difficult.
Quick Wind Tip
Always start your paddle session by traveling directly into the wind. That way, when you are tired and ready to head back, the wind will be at your back to help push you toward your launch point. If the wind catches you and you can no longer make forward progress while standing, drop down to your knees or lie flat on your stomach and paddle with your arms like a surfboard. This reduces your wind resistance and gives you more leverage to power through the chop.
Non-Negotiable Gear and Local Regulations
State Park rangers and local marine deputies strictly enforce safety rules on the lake of Colorado. They will give fines and restrictions to people who are not following the regulations (I have no personal experience with this, but I have seen it happen).
Life Jackets (PFDs): Every paddle boarder must have a US Coast Guard-approved Type III life jacket on board. Wearing it is the smartest choice, but at a minimum, it must be securely strapped to the deck bungees within arm’s reach.
Sound-Producing Device: You are required to carry a whistle attached to your life jacket or body. If weather conditions deteriorate or you need assistance, a whistle is the only way to signal for help over the roar of the wind. Many life jackets come with whistles attached.
You may also want to carry a dry bag for snacks, a beach towel to sit on (or dry off with), and sand toys if you’re going out with a kid. You can see my full list of tried-and-tested gear that I take out on the water with me here: Benable Gear List.
