The temperature of the air and water should not enter into the rating system
at all. I want to know that a class V in Alaska is the same as a class V in
Costa Rica. I'll use my judgement as a reasoning human being to figure out
that glacial melt in Alaska might require different gear than tropical
water. My local river at 3,000 cfs should be rated as class III after a
summer rain storm or in December when the water temp is about freezing.
It's the moving water that's rated, not the weather. or the gear or the
type of boat or the skill of the paddler. If you're a newbie, then a class
III could be a river of death, but knowing roughly what is meant by class
III should inform you enough to influence your decision to run the river.
The thing that has always bothered me about the rating system is that it
doesn't seem to take into account life-threatening features differently than
just big features. A line of bus-sized waves seems to sway the rating
higher, even though nothing dangerous would be likely to happen to a person
with average water savvy. If two of those ten waves are hard keepers, or
there are undercut banks, I'd like to see rating tons higher.
Maybe the rating scale needs to be like the Richter scale and have the
difficulty increase exponentially for every 0.1 point. (That's a class 4;
but a 4.4 after a heavy rain.)
Or maybe the tenth could be coded to mean something:
0.1 caution after heavy rains
0.2 parts of river inaccessible/unexitable
0.3 drops of death
0.4 open boats not recommended
0.5 big but not unfriendly
0.6 cold water - danger of hypothermia
etc.
I guess that might lead to class IV.3.4.6

Mike in Lunenburg, NS


"riverman" wrote in message
...
(This is a repost from another thread. I thought it might be worth its own
discussion.)


What do you think:
a) Two identically skilled paddlers in the same type boat,
on the same day, paddling the same river together. One is dressed
appropriately, one is underdressed significantly. Is the rapid rated the
same for each of them?
b) Two paddlers on the same river the same day, one is a novice, one is an
expert. Is the rapid rated the same for each of them?
c) One is in a canoe, one is in a raft. Is the rapid rated the same for
each
of them?
d) A rapid is rated a class 5 (unrunnable) in 1992, but since then, new
materials and techniques makes it quite runnable by advanced boaters. Is
it
still a class 5 rapid?

Most folks would say YES to questions a-c, and claim that the rapid rating
is based on the characteristics of the water, not the boater. But they
also
say NO to question d, although the rating is now being based on the
characteristics of the boater.

I was thinking about this on the way home, and began to get a grip on the
problem with the rating system, and why people argue enlessly about
whether
canoes can run class 4, or whether class 5 is runnable, or wheter a
certain
rapid ought to be downgraded once its been run enough times, or even if a
class 3 in an open boat is a class 3 in a squirt kayak.

With most quanititative measurements, the questions being asked are
innate,
and divorced from the observer. For example: how high is the wave at 5000
cfs? How fast is the current behind that rock? Whats the volume of water
at
4 feet on the guage? Asking the question implies measureing something
without actually interacting with or affecting the measurement. As a
result,
the answer is identical for all observers.

But when try to give a rating system to a river or rapid, we are asking a
very specific question: how hard is the river to run? That implies
explicitly that we are imagining someone interacting with that river,
which
means we have to clearly define who that person is. And as obvious as that
statement is (I guarantee that almost everyone reading this is saying
"well,
duh!"), as obvious as that question is, we go to great lengths to avoid
answering it! Rating systems try to quantify all sorts of unbiased,
measurable data: stuff like how much whitewater there is, how many rocks,
accessibility to egress and rescue, size of the waves, etc. Often, rating
systems try to avoid the 'how likely is an average boater to capsize'
types
of assessments, and they step fully into the trap: no one has ever clearly
defined who they are talking about, but they MUST because of the question
being asked.

The solution is simple. The first step has to be to clearly and
unambiguously define as much about that 'imaginary person' as possible.
What
boat, what clothing, what skills, etc. And that imaginary person has to be
standard for all rivers, everywhere. Of course, we can always invoke the
'reasonable man test', as they do in law. "A reasonable person in such a
situation", but I don't think the disparate types of boaters could ever
come
to agreement on what a standardized 'reasonable man' is. But until it is
clearly defined, any attempt to make a river rating system is doomed to
failure.

Anyway, my proposal: some recognized authoritative body must clearly
define
who the 'Reasonable Boater' is: what skills, what boat, what gear, as well
as what the environmental situation is: what temp (air and water), what
river level, what sky conditions are, etc. Then, all rating systems
worldwide would be correlated and usable. If a person was in a more stable
boat than the Reasonable Boater Standard, they could modify *all* river
rating worldwide by just adjusting the rating system on their local river
accordingly. Sort of their personal handicap.

In this way, a river's actual rating is meaningless. There is NO 'class 4
rapid', because no one is really the Reasonable Boater. But what is class
4
for YOU may be class 3 for someone who is a much stronger paddler, and
class 5 for a newbie. Which actually represents reality much more, since
people will argue all day about whether a class 4 rapid is runnable.

--riverman