rating rivers

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aldenb

rating rivers

Post by aldenb »

I am in the middle of writing a guidebook, and so i find myself thinking about rating rapids.

one thing that I am thinking about is American Whitewater's new system of rating drops class 5.0, 5.1, 5.2, ect. According to this system, moving from 5.0 to 5.1 is like moving from class III to IV. I don't know if I like this system. It seems like almost nothing is unrunnable anymore, so why have this reserved category of class VI? Why not just call stuff class VI or VII? If they have a race every year off Gorilla Falls and 65 people do it while very tired, and yet everybody is scared out of their wits on the Stikine Canyon, surely we can call one cl V and the other cl VI, no?

What is often funny to me is that I am constantly asking people how they would rate rivers, and there are so many different scales out there, nobody agrees! it seems like if someone portages a rapid it MUST be class V, if they're shaky it's class IV, if it's OK with them it's class III or class II.

i feel like with rating rivers you have to take in the difficulty and the danger as main things.

i dont know, just thought i'd throw some stuff out there for discussion or whatever. after all, it is winter!
Alden
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the great gonzo
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Rating rivers: Addison's Scale

Post by the great gonzo »

Alden, I agree with you that the current rating system is flawed in that it is not open and flexible enough and tends to downrate rapids.
Another problem is that the rating system puts objective difficulty as vell as consequences in the same number.
Recently I read an article by Corran Addison (don't know how old it actually is) where he proposes a new rating system.
It is composed of three parts:

A) Difficulty (how hard are the moves to sucessfully run a rapid, regardless of the consequences). His proposed scale is from 1 to 10 with the possibility to add higher numbers if more difficult rapids are run.

B) Danger (what are the consequences of a mistake), scale 1 to 6 with one being virtually no danger and 6 being virtually certain death.

C) Exposure, i.e. how far away is help.

This is, in my opinion, the best proposed rating system I have seen so far.

martin

here s the link to the article.

http://www.kendo.freeserve.co.uk/river%20grade.htm
Everyone must believe in something. I believe I'll go canoeing - Henry David Thoreau
Timzjatl
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Post by Timzjatl »

the current rating system also doesn't take into conscideration the type of rapid. If you spend all of your time in big water class 5.0, say the upper gauley, you certainly aren't prepared for class 5.0 creeks... I'd gladly run my playboat down a big water class 5, like say Lost Paddle on the Gauley, but I'd sure as heck rather have my creek boat for even class 4 creeks. However, with its faults, the current rating system does a good job of giving us an overall idea of the difficulty of runs, and the dangers involved. It is up to the paddler to find out all of the other neccessary information to make the descision for themselves wether the run is fit for him or her.
Just my .02
Jim
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Post by Jim »

Alden-

The following made the rounds a few years ago. Unfortunately, I do not know who wrote it, so I cannot give credit to a good author.

Jim


This is my suggestion for the new International Scale of River Difficulty: Someone asked an anonymous boater about his class IV comfort level and he answered something along the lines of "I'm comfortable that I can usually find an eddy to swim to." Thus, the interviewer was inspired to offer this International Scale of River Difficulty:

Class I: Easy Fast moving water with riffles and small waves. Swimming is pleasant, shore easily reached. A nice break from paddling. Almost all gear and equipment is recovered. Boat is just slightly scratched.

Class II: Novice Straightforward rapids with wide, clear channels which are evident without scouting. Swimming to eddies requires moderate effort. Climbing out of river may involve slippery rocks and shrub induced lacerations. Paddles travel great distance downstream requiring lengthy walk. Something unimportant is missing. Boat hits submerged rock leaving visible dent on frame or new gash in plastic.

Class III: Intermediate Rapids with moderate, irregular waves which may be difficult to avoid. Water is swallowed. Legs are ground repeatedly against sharp, pointy rocks. Several eddies are missed while swimming. Difficult decision to stay with boat results in moment of terror when swimmer realizes they are downstream of boat. Paddle is recirculated in small hole way upstream. All personal possessions are removed from boat and floated in different directions. Paddling partners run along riverbank shouting helpful instructions. Boat is munched against large boulder hard enough to leave series of deep gouges. Sunglasses fall off.

Class IV: Advanced Water is generally lots colder that Class III. 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 experienced while about to swim large drops. Frantic swimming towards 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 permanently removes waterproof box with all the really important stuff. Paddle partners running along stream look genuinely concerned while lofting throw ropes 20 feet behind swimmer. Paddle partners stare slack-jawed and point in amazement at boat, which is finally pinned by major feature. Climbing up riverbank involves inverted tree. One of those spring-loaded pins that attaches watch to wristband is missing. Contact lenses are moved to rear of eyeballs.

Class V: Expert The water in this rapid is usually under 42 degrees f. Most gear is destroyed on rocks within minutes if not seconds. If the boat survives, it is need of about three days of repair. There is no swimming, only frantic movements to keep from becoming one with the rocks and to get a breath from time to time. Terror and panic sets in as you realize your paddle partners don't have a chance in hades of reaching you. You come to a true understanding of the terms maytagging and pinballing. That hole that looked like nothing when scouted, has a hydraulic that holds you under the water until your lungs are close to bursting. You come out only to realize you still have 75% of the rapid left to swim. Swim to the eddy? What #%^&*#* eddy!? This rapid usually lasts a mile or more. Hydraulic pressure within the first few seconds, removes everything that can come off your body. This includes gloves, shoes, neoprene socks, sunglasses, hats, and clothing. The rocks take care of your fingers, toes, and ears. That $900.00 dry suit, well it might hold up to the rocks. Your paddle is trash. If there is a strainer, well, just hope it is old and rotten so it breaks. Paddle Partners on shore are frantically trying to run and keep up with you. Their horror is reflected in their faces as they stare at how you are being tossed around! They are hoping to remember how to do CPR. They also really hope the cooler with the beer is still intact. They are going to need a cold one by the time you get out! Climbing out of this happens after the rapid is over. You will probably need the help of a backboard, cervical collar and Z-rig. Even though you have broken bones, lacerations, puncture wounds, missing digits & ears, and a concussion, you won't feel much because you will have severe hypothermia. Enjoy your time in the hospital, with the time you take recovering you won't get another vacation for 3 years.

Class VI: World Class Not recommended for swimming.
aldenb

boatin

Post by aldenb »

jim, that is GREAT! i bet the guy who wrote that was an open boater. I used to go boating with an open boater friend down south, he would swim nasty rapids all the time. usually he'd be in his boat smoking a cigarette at the top of the rapid, and by the end he was doing the backstroke. a real yahoo. right out of the "paddlesnake" videos!

i remember reading that tom mcewan used to make his kids swim rapids to get comfortable, to "de-mystify" the river. i think this is a good excercise. i used to force myself to swim nantahala falls, that was actually kind of scary! not to mention FREEZING! i just always want to keep swimming in the back of my mind.
Alden
DanielHolzman
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River rating compated to rock climbing

Post by DanielHolzman »

The "Coran Addison" system of rating referred to has actuallly been around a long time in the rock climbing community, where it works very well. In climbing, the difficulty of the moves is rated from 0 to (currently) 15, with an open end to accommodate ever more difficult climbs. The first number of a climb, before the decimal point, is related to the need for fall protection, thus a class 5 climb requires a rope, a class 4 climb a rope is recommended but not considered mandatory.

Thus, a climb rate 5.9 means rope required, degree of difficulty 9. On the more difficult climbs, typically 10 and higher, the climb may receive a letter suffix from A to D, with A being the easiest, D the hardest, thus 5.10A is easier than 5.10D.

The difficulty of protecting a climb using normally available gear is typically indicated with either a G (good protection), R (limited protection), or X (death wish climb, minimal or no protection possible). Note that this rating has absolutely nothing to do with the difficulty of the moves, thus a 5.5X climb tells you that the hardest move is grade 5, but protection is sketchy to non-existent.

The sustained difficulty of a climb is typically noted in the route description, thus a climb with a single 10 move is rated 5.10, same as a climb that is sustained 5.10, clearly far more difficult, but not indicated in the rating, which refers only to the difficulty of the hardest single move on the pitch. However, note that climbs are typically rated pitch by pitch (pitch is a sustained segment of climbing between belay stances).

The difficulty of access to a climb, and problems associated with remoteness, evacuation, and length of climb, are often addressed via an alpine system that rates climbs by CLASS, with a class 5 climb being a multi-day climb featuring bivouac on the rock. This system is somewhat less successful than the decimal degree of difficulty system, in my opinion, because rapid, alpine style ascents have radically altered the time it takes for competent, in shape climbers to ascend routes. For example, climbers in Yosemite have successfully ascended TWO previously multi-day routes in a single day, thus calling into question the meaning of a class 5 designation for the climbs.

So, to relate this all to boating....

To adopt a system like this, we would need to rate the individual river segments on a decimal system from 0 to open ended, where 0 would indicate essentially flat water, and a 10 might indicate a very difficult rapid, possibly equivalent to a 5.2 under the AWA system. The danger factor could be rated from G to X, with rapids like Dimple on the Yough rating an X due to numerous fatalities, whereas say 7 foot falls on the Chatooga might rate a G due to ease of rescue and limited danger factor. The remoteness factor could be handled in the river commentary, as it is typically handled today.

The AWA (and the Keelhaulers, and probably other groups) have published standardized ratings of rapids based on difficulty, and there would be little difficulty adjusting a decimal rating scale of difficulty to the standardized lists already published. The risk factor would be based on relatively objective standards such as presence of sieves, strainers, or other hazards, possibility of entrapment, presence of potentially fatal holes etc.

One important difference between rock climbing and rivers is that the rock climb is presumed to be static, whereas the difficulty of a river may vary widely with flow. Thus is may be necessary to assign different degrees of difficulty to a river based on cfs, but this is commonly done in guidebooks anyway, whereas I have never seen a rock climbing guidebook indicate that a 5.9 would be a 5.11 in rainy weather, for example.

Conclusion: the key to a workable system is to separate difficulty of move, danger of rapid, and remoteness of the run, since these factors are typically independent and should be evaluated as such. Whether we use the AWA or a decimal system is not nearly as important as separating the three factors.
aldenb

boatin

Post by aldenb »

hey daniel,
very interesting. i had no idea climbing had a system for rating degree of danger. when i see climbs rated (like in magazines) I never see an X or G or anything like that.

you raise an interesting thing though, and that is: if there is a class V move on a class III river, what do you rate the river as a whole. You defnitely clarified my thoughts about one particular river, where the crux is unportageable. that river is getting cl V
Alden
NZMatt
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CLimbing Ratings

Post by NZMatt »

HI Alden, Daniel and y'all

If you want some more info on clmibing ratings, check out the british system. I can't remember the exact details, but it includes both a rating for the hardest move on the climb, as well as a "word" rating (e.g. severe) for the overall difficulty of the climb, which incorporates exposure, distance from rescue, and other potential hazards. There may also be a rating for the protection, but I can't recall.

The main thing that is true for all the climbing grading systems (and there are many of them, e.g. in Australia and New Zealand we use a system that is open ended, a simple numeric and currently has the highest rating set somewhere around 36 - corresponding roughly to the American 5.14d, but I digress) is that these are all OPEN ENDED systems and that is one area where the current river rating system truly fails.

As you note, there needs to be an accounting of flow in any rating system, but you also need to realise that there will be regional variations in how hard a grade really is. In climbing, 5.10 at the Shawangunks in NY is significantly harder than 5.10 in Yosemite. Similarly, a black diamond in skiing varies significantly in diffculty from ski field to ski field and also from region to region. The climbing and skiing systems are useful models, and may provide a starting point, but the inherent differences of paddling may require different solutions.

Just some thoughts.

Good luck!

Matt
NZMatt

Hmmm....new country, new rivers...-
Still not enough c-boaters....
Kalifornia_Kid
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no perfection

Post by Kalifornia_Kid »

:roll:
There are too man different kinds of whitewater to ever acheive a perfect system. Just my opinion of course. But even if you could devise an absolutely perfect system (by the way, I think the new system kinda bites), people would still argue about what class a rapid is, and why its rated that way. Ultimately, the burden has to be on the paddler, not a guidebook or a rating. You look at the rapid, consider you options, (i.e. consequences, exposure, etc) and then you make a decision. If you screw up bad in a place you shouldn't, a class III can kill you just as easy as a V. As for the guidebook, I've helped write a couple, and your disclaimer should say something like (these ratings are only an estimation and only legit at normal flows, 1000 to 3000, or whatever, also, obstacles not listed in the guidebook may appear at any time). If you try and make it too exact and meticulous, like pointing out precise routes, you're just leaving yourself open for a lawsuit.
Good Luck
Kalifornia Kid
Camille
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objectivity

Post by Camille »

It seems to me that it is impossible to objectively classify a river. As noted in most guide books, ratings are arbitrary guides at best. Besides the difference between east coast and west coast rivers, new school and old school boaters, and c-1, kayak, and open boaters will greatly change what rating you're going to get. For a guidebook I like the idea of keeping around the I-VI system just because people are used to it but begin to incorporate some of the other (great) ideas that have been discussed.

good luck with the book-where/what are you covering?
camille
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