International Scale of River Difficulty 

I; Easy
Fast moving water with riffles and small waves. Swimming
is pleasant, shore is easily reached. Almost all gear and equipment
is recovered. Boat is slightly scratched.

II; Novice
Straightforward rapids with wide clear channels which
are evident without scouting. Swimming to eddies may require moderate
effort. Climbing out of river may involve slippery rocks and shrub
induced lacerations. Paddles travel a great distance downstream
requiring a lengthy walk. Canoe hits a submerged rock leaving a ding
on gunwale.

III: Intermediate
Rapids with moderate irregular waves which may
be difficult to avoid. Water is swallowed. Legs are repeatedly ground
against sharp pointy rocks. Several eddies are missed while swimming.
Difficult decision whether or not to stay with boat is made. Decision
to stay with boat results in moment of terror when swimmer realizes
they are downstream of boat. Paddle is recirculated gently in small
hole way upstream. All personal possessions are removed from boat and
floated in different directions. Paddling partners run along river
bank shouting helpful instructions. Boat is munched against a large
boulder hard enough to leave serious gouges. Sunglasses fall off.

IV: Advanced
Intense powerful but predictable rapids requiring
precise swimming in turbulent water. Swimming may require “must”
moves above dangerous hazards. “Must” moves are downgraded to
“strongly recommended” after they are missed. Sensation of
disbelief is experienced while about to swim large drops. Frantic
swimming toward shore is alternated with frantic swimming away from
shore to avoid strainers. Rocks are clung to with death grip. Paddle
is completely forgotten. One shoe is removed. Hydraulic pressure
removes car keys and credit cards from zippered paddle jacket pocket.
Paddle partners running along river bank look genuinely concerned
while lofting throw ropes 20 feet behind swimmer. Paddle partners
stare slack jawed and point in amazement at the canoe which is
finally stopped by a major feature. Climbing up the river bank
involves an inverted tree. One of those little spring loaded pins
that attaches watch to watchband is missing. Contact lenses are moved
to rear of eyeballs.

V: Expert
Not recommended for swimming.