Terms + Concepts to Know
Rocks Make Whitewater: Is the rock friendly or not friendly?
Friendly rocks are fun
They create pillows, water flows smoothly over them, paddlers can bump into and off them or paddle over the top of them safely.
Unfriendly Rocks
Create dangerous situations. Be aware of the following
- Undercut Rocks: Create a siv that can entrap or pin boats or humans.
- Thin or sharp rocks: Paddlers or boats can get stuck on these rocks. They don’t create pillows, water rushes quickly by them.
RIVER FEATURES
Holes: Where the water rushes over a rock and creates a trough that the downstream water fills and that can create a foam pile.
Foampile: Upstream rushing water in a hole. The white and lighter color part.
Boil Line: The point where the water starts going downstream again and above which the water rushes upstream.
Corners: Where the foam pile disappears on the outside of the hole.
Hole Shapes
What the Foam Pile looks like in the river and how it takes up space.
Straight Hole: Foam pile runs straight across the river
Smiley Hole: The corners of foam pile are further downstream than middle.
Pocket or Frowney Hole: The corners of Foampile are further upstream than middle.
Diagonal Hole: Yup, the foam pile runs diagonally across the water.
Waves
What you play on when in whitewater, you bounce up and down, you can surf them. Waves can be so much fun on the river.
Peak: Top of wave
Trough: Bottom of wave
Shoulder: To right and left of the wave where wave begins to disappear into the current of the river.
Eddies
Slow water and slack water in a river created by an obstacle in the river or shoreline.
Top of an eddy: Very most upstream side, usually up against a rock or shoreline.
Bottom of eddy: Most downstream part where the eddy turns back into the current
Eddy Pocket: The most stationary or upstream-moving part of the eddy.
Eddy Lines: Separate the current going downriver from the upstream running slack water.
Crisp or Clear Eddy Lines: Sharp line between current and eddy
Boily, Wide or Mushy Eddy Lines: Not as distinct line, current fades into eddy
Picking your Paddle Line
When paddling whitewater, you will generally be moving from one eddy to the next eddy. From eddy to eddy, you will assess for your paddleable line taking the following items into consideration.
- Know what paddling techniques you’re good at to pick your line either paddling the easiest way through or using your skills to move through the line.
- The fastest current usually is denoted by waves or a V.
- The V shows the fastest current and oftentimes goes between the rocks. Water in a V is deep and moving so it’s a good choice for line selection.
- Look for obstacles such as holes and rocks, etc. along your chosen line to determine how you want to handle them.
- Number 1 Priority is to leave as much margin for error in your line as possible so if something goes not according to plan you have time to read what’s coming and calibrate your line.
Consider the Following Obstacles
Tunnel Vision: When a paddler looks right at the front of their boat rather than to the next eddy or obstacles along their line. Always focus on the target or where you want to go rather than right in front of your boat.
Fun with rocks: You can paddle around them, Catch the eddy behind them and if there’s enough water, paddle over them. Rocks sticking up above the waterline in the middle of the river is a pretty good indication that there’s an eddy on the backside of it.
Be aware of Current Differential: There can be a strong or smooth difference in speed between the current flow and the strength of the eddy and it’s important to know what those differences will mean for you.
River Rapid Class-ification: Choose your adventure
Knowing the skill level and experience of those adventuring with you allows you to choose the right river stretches [with paddleable features] for your group. There are six different whitewater rapid class levels to choose from, with different characteristics in each class.
General Classification Notes
- Class 1: Class 1 offers moving water with small waves and a few riffles. There are few to no obstructions, making this the easiest option for those who are new to whitewater rafting adventures.
- Class 2: Obvious, clear channels, small waves, and easy rapids signify class 2. These rapids are still fairly easy, but generally require a bit more maneuvering than class 1.
- Class 3: In class 3, you’ll find narrow passages that may require significant maneuvering, as well as rapids with higher, sometimes irregular waves. Class 3 is a good option for intermediate adventurers.
- Class 4: Very narrow or constricted passages and long, difficult rapids are some of the markers of a class 4 course. You may have to deal with cross-currents and powerful waves, as well as aggressive water. Class 4 may also require some scouting and the course isn’t always very clear.
- Class 5: If you are an experienced whitewater rafter, class 5 is still a difficult, and sometimes dangerous, choice. You’ll find violent rapids with high torrents, as well as obstacles that are extremely hard to maneuver. Class 5 should be left to experts, as even when you know what you’re doing, it can be a dangerous ride.
- Class 6: It is extremely dangerous to try to beat a class 6. In fact, these rapids are generally not commercially raftable, and should only be taken on by teams of experts. Even then, they are life-threatening and nearly impossible to navigate. Class 6 includes the fastest moving water, extremely turbulent waves, cross-currents that are nearly impossible to move through, and more. There is a very real and present risk of life with class 6 rapids.
Keep in mind that the classification of the water you plan to navigate is not set as a challenge, but instead as a safety precaution. You can find a guidebook for the section of river you plan to paddle to get an idea of what rapids, campsites, hikes, and geographic and historic features you will encounter on your adventure. It’s important to fully know and acknowledge your skill level and the kind of adventure you want to have and match it to the right classification and stretch of water you will paddle.