The International River Grading System
Where gradings are given for rivers or sections of rivers, they conform to
the International River Grading System which is described below. Uses described
are those commonly in practice for each grade. It is the responsibility of
canoeists or group leaders to decide whether a section is appropriate for their
personal experience and skill level, or that of their charges, for the use they
intend; and to obtain necessary consents for a particular use.
Rivers with long, flat stretches of slowly moving water with occasional
simple rapids, waves low, course easy to steer.
Use: Inland touring, instruction of novices and possibly racing and touring
events. In flood conditions these sections are often high volume and the
'normal' characteristics are replaced by a much higher graded flow. Trees along
the normal channel may create difficulties.
Fairly frequent rapids, usually with moderate regular waves or easy eddies.
Use: Touring for proficient canoeists. Moving water skills required. May be
suitable for teaching such skills. White-water races and lower-division slalom
competitions. In flood conditions the technical difficulty increases
dramatically and the river may only be suitable for proficient canoeists. These
sections have a steeper gradient and may include obstructions within the
Rapids numerous with fairly high irregular waves, broken water, eddies and
boils. Course not always recognisable. Inspection from the bank sometimes
Use: The proficient white-water canoeist will seek out this grade of water.
Generally the grade is given because there are a series of steps which give
relatively short stretches with a steep gradient. There will always be technical
difficulty with steering and route choice, Suitable only for canoeists with
well-developed skills. Used for training for advanced proficiency and white
water competition, short stretches suitable for slalom competition, longer
stretches for white-water racing. In flood the technical difficulties are often
increased by the dramatic change in the water features: waves are higher;
stoppers deeper and hold the canoe/kayak more easily.
Very difficult, long extended stretches of rapid with high irregular waves,
difficult broken water, eddies and whirlpools - course often difficult to
Use: Sought by the committed white-water canoeist. Used for International
slalom competition and white water racing. Generally the river will have a
stepped profile, much of the grade will be because of the waterfalls or drops up
to 3m high. The channel is often narrow and steep sided. It is often necessary
both to inspect the section from the bank and prepare bank
support as a safety standby. Canoeists will not choose to swim in this grade
of water if avoidable. Unlikely to be used for training. In flood some sections
wash out, others will be one or even two grades higher.
Water features are similar to grade 4 but they are larger and less
predictable. Course always very difficult to choose and will involve significant
risk to the canoeist and equipment.
Use: These sections are usually relatively short and will always be inspected
from the bank. There will always be a need for bank support for safety. In
flood, if the section is not washed out, it may be considered too risky as even
a moderate change in volume may alter the grade significantly. Only the most
proficient canoeists, in small teams, will attempt this type of water. Not used
for competition or events.
This is at the extreme limit of canoeing. Definite risk to life.
Use: These sections usually have a steep gradient or may be a single large
fall. The section will usually be paddled when there is a low volume of water
and there will always be significant bank support - often involving
pre-placement of rescue lines.