Home |
Search |
Today's Posts |
#6
|
|||
|
|||
"Mike Taylor" wrote in message ... 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 Hi Mike: You're falling into the trap. While I understand the desire to rate rivers based on the features of the water (as you say: "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"), my point is 'the moving water is rated in comparison to WHAT?" You use (as is common, and standard) such terms as "life-threatening features", "big features", "dangerous", and "keepers" to determine river grading. But those terms are variable: what is 'life-threatening' or 'dangerous' will vary greatly on the paddler skill, boat style and material, water temps, and a host of other factors. "Big" to an open canoe can be 'miniscule' to an 18 foot, 2 ton row boat. What is a 'keeper' to a kayak may be a mild splash to a 28-foot snout rig with two outboards. What may be 'life threatening' (even such things as low-head dams or strainers) may be merely 'cautious' to someone who is a solid paddler with experience around and in these thigs. Even your proposed scale uses terms like "big, but not unfriendly". Big to whom? Unfriendly to whom? That does not mean the same thing to all boats or boaters. Now, imagine that we are talking about a kayaker, in a playboat like an old Perception Mirage (I'm dating myself here), not a squirt boat, and they are well-acquainted with the river; it's 'home water'. Let's assume it is midseason, define this kayaker as wearing appropriate clothing, they are in a group large enough to provide adequate safety at any rapids, give them solid skills (this will need to be more well-defined, but lets agree that they have a dependable roll in all but the worst keeper holes, can high and low brace all day, and if they gave driver's licenses for kayaks, they'd have one). Now, when the rapid is rated a class 3, it's class 3 for them, and this has some meaning we can work with. You, on the other hand, have a low-volume squirt boat, are a bit shakey in your skills, and have never seen the river before, and are paddling with only me. The guidebook rates it Class 3.2, which means "Class 3.2 for our 'Standard Boater'. You say "OK, I'm in a smaller volume boat, thats .25 grade higher. I'm also a beginner in this style boat, thats another .5 grades higher, I don't know the river; add another .1 grade, we're alone (add another .25) and the water temps are much colder than usual (its a late fall trip), so add another .1. The result; its a Class 4.4 for me. I am not personally comfortable running anything over class 4.0, so I'm skipping this." I, on the other hand, will say "OK, I'm in a raft, that makes the rapid 2 grades easier. We're alone (add .25), I'm a solid oarsman, so there's no modification there. The water temps won't affect me, so there's no modification there, and I don't know the river, so add .1 to the grade. That makes the rapid Class 1.55 for me, so not only am I going to run it, but I'll carry you and your boat on through." Similarly, we come across an unrated rapid. In the current system, we might debate the rating. I'll say "it looks simple for my raft, just some rocks and splashy waves; its a class 2-3" and you'll say "hell, no! In my kayak, its very tricky. That's a class 4!" The result is what we have today; a TON of class 3+/4- rapids, with little continuity between them. But in this new system, despite our different boats and different skills, we look at this rapid for the sake of our 'Standard Boater'. With him (or her) in mind, we will easily and quickly agree on the river rating (say, class 3.5), and then modify it for each of our own situations. No matter what happens with future developments in materials or styles, the rating that we give this rapid will not change. Just the new equipment will change the rating for the paddlers. --riverman |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Problem with 3 hp Sears Gamefisher / Tanaka 300 | Boat Building | |||
DRAFT: June-Dec 2003 Whitewater Accident Summary | General | |||
Digital maps for Nahanni/Keele River systems | General | |||
back with a problem now | General | |||
Thoughts on volume (CFS) and river levels and such (sort of rambling) | General |