Marc's WhiteWater Gear Reviews

River Kayaks Explained

River kayaks are designed primarily for downriver paddling.
In general, river runners are designed for down-river speed, catching eddies, and the occasional surf on a green wave (while creek boats are designed to run tight, steep, and technical whitewater).
There are a few design characteristics set river boats apart:
Weight, rocker, edge profile and volume distribution.

The same principles do apply on WhiteWater River Canoes.

Weight

We’ll start with the most obvious. Weight is not your friend. Neither kayaking, loading it onto your car, during portage or in a rescue and retrieval situation.

Rocker

The term rocker refers to the curvature or angle of a boat’s hull toward the bow and stern. Boats with longer effective waterline / lower rocker are faster but do not turn as easily as boats with shorter effective waterline. Boats with longer effective waterlines typically are better suited to river-running, where speed is key to moving through large waves and holes and the boat needs to avoid being easily knocked off line.
Shorter waterlines / higher rocker tend to be slower but turn more easily. These boats are better suited to more technical whitewater where maneuverability is more important than speed.

The shape of the rocker largely determines how a boat will behave when entering the water from a vertical drop (i.e. a waterfall). Boats with rocker that remain constant as you move toward the bow or stern (called linear rocker) have a smaller possible range of boat angles that still allow the bow to stay on the surface when landing a vertical drop.
These linear rocker are common on river-runners.

Edge

Hard edges provide a “keel line” (a linear feature that resists spinning in the water) when the boat is put on edge, which allows the boat to maintain momentum moving in a relatively straight or broadly curved, trajectory. This makes boats with hard edges excellent at “carving” in and out of eddies when moving down river. Hard edges also allow for more dynamic surfing, providing good directional boat control on a wave. As a result, hard edges are more common on river running boats. The drawback of hard edges is that they provide a place for water to pile up, or “catch,” on the boat, and they can hang up more on rocks. This makes boats with hard edges more challenging to paddle in boily and dynamic water, as well as shallow rivers that involve maneuvering over, around, and on lots of rocks.

Volume displacement

When volume is centered on the cockpit of a boat, the ends tend to be thinner in profile. Such boats feel “sportier” because the bow and stern engages the water more. This also allows the paddler to make dynamic moves like squirts more easily, and usually results in more maneuverability while surfing (because of less weight and volume in the ends). For these reasons, river running boats tend to have proportionally more of their volume around the cockpit than in the bow and stern.

Creek Kayaks Explained

Creek kayaks are designed primarily for downriver paddling.
In general, creek boats are designed to run tight, steep, and technical whitewater (while river runners are designed for down-river speed, catching eddies, and the occasional surf on a green wave).
There are a few design characteristics set creek boats apart:
Weight, rocker, edge profile and volume distribution.
The same principles do apply on WhiteWater Creeking Canoes.

Weight

We’ll start with the most obvious. Weight is not your friend. Neither kayaking, loading it onto your car, during portage or in a rescue and retrieval situation.

Rocker

The term rocker refers to the curvature or angle of a boat’s hull towards the bow and stern. Boats with longer effective waterline / lower rocker are faster but do not turn as easily as boats with shorter effective waterline. Boats with longer effective waterlines typically are better suited to river-running, where speed is key to moving through large waves and holes and the boat needs to avoid being easily knocked off line.
Shorter waterlines / higher rocker tend to be slower but turn more easily. These boats are better suited to more technical whitewater where manoeuvrability is more important than speed.

The shape of the rocker largely determines how a boat will behave when entering the water from a vertical drop (i.e. a waterfall). The advantage of a progressive rocker is twofold:
first, it takes stress off the paddler’s back when landing larger drops, a
nd second, it allows for more efficient transfer of vertical energy (from falling) into horizontal energy (moving quickly away from the hole at the bottom of the drop).
This makes progressive rocker very desirable on creek boats and less common on river-runners.

Edge

Creek boats with indistinct or soft edges tend to have a “mushy” feel, because they do not engage with water as much as hard edges. They do allow for faster “pivoting” turns, however, as well as smoother moves off rocks, and do not get hung up in boily water as easily. Creek boats tend to have softer edges.

Volume displacement

Boats with proportionally more of their volume distributed into the bow and stern tend to resurface more quickly and under more control. This is the result of increased buoyancy in the bow and stern.
They also tend to be more resistant to burying the bow off ledges, and punching holes (instead they ride over holes).
For these reasons, creek boats tend to have more volume distributed in the bow and stern than river-runners.

Kayaks

The White Water River and Creek

‘Whitewater is formed in a rapid, when a river’s gradient increases enough to generate so much turbulence that air is entrained into the water body, that is, it forms a bubbly or aerated and unstable current; the frothy water appears white. The term is also loosely used to refer to less turbulent, but still agitated, flows. The term “whitewater” also has a broader meaning, applying to any river or creek itself that has a significant number of rapids.’

The Kayak / Canoe

There are five main “categories” in whitewater kayaking, and thus, Kayaks:

River running

A principal design characteristic of riverrunning kayaks is their comparatively longer length and narrower breadth. The longer length at the waterline not only helps to carry speed but the longer arcs thus created between stem and stern allow the boater to more efficiently and gracefully carve into, through and out of eddies and other currents.
(More on this topic can be found on this River Kayak page.)

Creeking

Creek boats usually have increased “rocker,” or rise, fore and aft of the cockpit for manoeuvrability.
(More on this topic can be found on this Creeking Kayak page.)

Slalom

Pro level slalom competitions have specific length (350 cm (140 in) for kayaks), width, and weight requirements for the boats, which will be made out of kevlar/fiberglass/carbon fiber composites to be lightweight and have faster hull speed. Plastic whitewater kayaks can be used in citizen-level races.

Playboating

Kayaks used for playboating generally have relatively low volume in the bow and stern, allowing the paddler to submerge the ends of the kayak with relative ease.

Surf kayaking
(‘out of category’, but relevant)

There are a number of speciality surf kayak designs available. They are often equipped with up to four fins with a three fin thruster set up being the most common. Speciality surf kayaks typically have flat bottoms, and hard rails, similar to surf boards. The design of a surf kayak promotes the use of an ocean surf wave (moving wave) as opposed to a river or feature wave (moving water). They are typically made from glass composites (mixtures of carbon fiber, Kevlar and fiberglass) or rotomolded plastic. Many kayaks, such as those used in whitewater kayaking on rivers or tidal rapids, are used. Many whitewater designs can be fitted with fins, to assist in control on moving surf waves.