Touring - Fording deep rivers

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pedalwhirl
08-03-08, 03:04 AM
Hi
I´m planning a tour which will take me through some very rough mountain roads. There are numerous unbridged waters on the way which need to be forded.
So how do you cross a river that is more than knee deep?
Does one have to carry the bike over in order to keep the hubs and drive train dry?
Or is it OK to walk the bike over, oil the chain, mount and go?
Try to keep the hubs and BB out of the water as much as possible, even if they have cartridge bearings.
Do you have experience in fording deep rivers by judging their flow? It's not something to be toyed with, as a moderate to fast current will sweep you away, even if knee deep, and if you get trapped underwater on the upriver side of a snag, you won't survive. This happens a lot in Australia with fresh-water anglers.
I would suggest an inflatable mattress (of the old type that you blow up and are not self-inflating). You can then float your items across. Also, I would suggest taking with you a long piece of rope to tether you to at least one shore should you get into trouble. A ship's chandlery should be able to help with something that is lightweight, strong and of a thickness that will suit your needs.
It might seem being overprepared, but from what you are implying, I would prefer to be overprepared rather than underprepared.
pedalwhirl
08-03-08, 06:19 AM
well... I´m actually studying hydraulic engineering so I hope I´ll be able to cross a river without killing my self :)
Well the good thing is that this tour is following a mountain road and the rule of thumb is that you cant drive over a river which can not be waded (If the ford looks nasty you put your waders on and try to wade it first, before you go in on your 4x4), so all of these fords should be wadable, at least in the morning...
jamawani
08-03-08, 06:57 AM
well... I´m actually studying hydraulic engineering so I hope I´ll be able to cross a river without killing my self
I would be less worried about my hubs -
And more worried about my own safety.
You give very little info, but enough to suggest considerable risk.
You say mountains - which implies faster moving water and colder water.
An unbridged road with knee-high water will have very little traffic.
Holding your bike over your head INCREASE your center of gravity.
Hikers drown every year making unsafe stream crossings.
Anything more than knee high and fast moving is very risky - esp. solo.
A light inflatable raft is one alternative. And a prudent one.
staehpj1
08-03-08, 06:57 AM
Maybe I'd be abusing my bike, but knee deep wade able water I would probably just push my bike through. I have never needed to do this on tour, though. I have ridden or pushed through knee deep water many times on a MTB though and never found it to be all that bad on hubs and BB although I did use boat trailer grease on those bikes. I would think modern sealed bearing would be fine and if you have cup and cone bearings I would just repack a bit sooner if in doubt.
staehpj1
08-03-08, 07:17 AM
I would be less worried about my hubs -
And more worried about my own safety.
You give very little info, but enough to suggest considerable risk.
You say mountains - which implies faster moving water and colder water.
An unbridged road with knee-high water will have very little traffic.
Holding your bike over your head INCREASE your center of gravity.
Hikers drown every year making unsafe stream crossings.
Anything more than knee high and fast moving is very risky - esp. solo.
A light inflatable raft is one alternative. And a prudent one.
Good points on the safety issue, but...
It doesn't need to be more than knee deep to be dangerous. It is quite possible to be swept away and under a snag in knee deep water if it is swift and you lose your footing.
A wading staff to lean on helps a lot. Using your bike to lean on can actually work very well, at least up to knee deep. Keep the bike on your downstream side and keep a good bit of your weight leaned on it. This assumes that the bottom is flat and smooth enough. If it is dicey move one foot at a time with the bike braced in place and move the bike only when both feet are planted. Carry the Panniers over on a separate trip using a staff of some sort if necessary. If the water is too swift/deep to do that safely, don't cross.
If necessary find a place up or down stream that is safer.
In still or slow moving water holding the bike over your head or floating it on some kind of raft might be fine even if the water is a good bit deeper. I wouldn't do either in swiftly moving water.
It is actually fun to practice these techniques in a place where you know you will only be flushed into a shallow pool. When I was ww kayaking we usually spent 1 day a year drilling on some of these techniques as part of a rescue techniques session.
If unsure, don't attempt it.
Bekologist
08-03-08, 07:58 AM
I foresee complications fording a river with a bike.
rules of thumb fording rivers:
wading staff held upstream- heavier current, use a heavier log. like, a big one - the size of your leg and 8 feet long!, to help break the current and weight you down as you lean on it. upstream.
don't tie yourself to any rope on shore...wrap it around the staff or your hand, but don't tie it onto yourself- that's a good way to get held under once you loose your footing.
I haven't tried it, but wonder if rolltop ortliebs would offer enough flotation for a loaded bike to be floated across?
alternately, Sevlor makes a very lightweight nylon backpackers raft designed specifically to ford rivers and cross lakes, etc.
staehpj1
08-03-08, 09:17 AM
wading staff held upstream
I don't know if there has been a recent change in thinking on this, but...
This is counter to what I was taught in ww rescue classes and also to what is printed in The Orvis Fly-fishing Guide. I don't claim to know for sure how using the staff upstream will work because I have never tried it, but I can say that I have used one downstream in classes, in normal stream crossings, and in rescue situations and the technique has been effective. It works well, but I would advise practicing it in relatively controlled conditions before relying on it in a more dangerous situation.
staehpj1
08-03-08, 09:20 AM
I haven't tried it, but wonder if rolltop ortliebs would offer enough flotation for a loaded bike to be floated across?
I wondered the same and bet they would, depending on what was in them. I know that my old 80's style MTB floats for a bit when naked until the frame tubes fill.
Bekologist
08-03-08, 08:01 PM
sourdough advice fording streams is wading stick upstream to break the current. surprised ww rescue would instruct opposite how river hydraulics operate.
see the illustration at http://www.wilderness-survival.net/crossing-1.php
this is river crossing 101 - ford with pole on upstream side.
I would also strongly suggest that panniers are removed from the bike and taken across separetely. Waterproofness is irrelevant, but the additional surface area and force might be very relevant.
In addition, scope out the crossing, whether it is well used or not, with a staff at least to see if there are any washaways or holes that you might stumble into. What you see through the surface sometimes is not what you get underneath with rushing water.
If you are wearing shoes like Shimano MTB ones, check how slippery the soles are on wet rocks. You might be in for a bit of a shock -- the MTB shoes I have are not at all good in those circumstances. And the cleat could interfere with good footing right when you need it.
You might be a hydraulics engineering student, but overfamiliarity or overconfidence with *anything* to do with water can be fatal.
You also should keep a check somehow on prevailing weather conditions upstream. There have been several tragedies involving canyon rafters caught out by raging torrents resulting from torrential downpours further up in the mountains. One occurred not so long ago in Europe.
pedalwhirl
08-05-08, 12:46 AM
Hi, thanks for all your answers.
I stumbled into some advices from a guy that has done the same route as I was planning. I have translated them and...
Never overestimate yourself. My respect for these rivers has been growing year by year.
4°C cold and gray glacier rivers should be enjoyed with precaution, you can not see to the bottom.
Glacier rivers usually have quite high flow velocities.
Should the glacier river look too dangerous to cross, wait till the next morning, most of these rivers run shallow in the early hours
Wait, if possible, for a jeep to cross first and observe the depth and currents. If you get offered a lift over a dangerous river, accept it!
The depth is usually less up and downstream of the jeep fords.*
Freshwater rivers are usually around 8°C and can be crossed relatively easily at depths up to 60 cm, given that the current is not to strong
Always keep your bike on your down stream side. That way it won´t get pushed at you if things go bad.**
Never cross perpendicular to the current, cross at a 45° angle, heading upstream, that way the lateral forces will be less***
* It is right that the fords tend to be deeper, they usually consist of a main pool, and at the downstream end of that pool a small break can be seen in the surface of the water where it returns to its undisturbed riverbed, that is where you want to cross!
** I guess this makes sense, but I would be inclined to have my bike on the upstream side, to break the current so I would be able to stand more securely.
*** Intuitively I would do this in the downstream direction, just as you cross on a 4x4.
Dan The Man
08-05-08, 10:08 PM
I graduated from mechanical engineering, and I can say with confidence that understanding fluid dynamics, or hydraulic engineering has absolutely nothing to do with wading across a river.
I thought this thread was a metaphore
pedalwhirl
08-06-08, 01:36 AM
I graduated from mechanical engineering, and I can say with confidence that understanding fluid dynamics, or hydraulic engineering has absolutely nothing to do with wading across a river.
how can knowing alluvial channel hydraulics and river morphology not benefit you while crossing a river?
Dan The Man
08-06-08, 01:38 AM
The same way that I know trigonometry doesn't teach you how to be a pool shark.
pedalwhirl
08-06-08, 01:42 AM
no, but it should get you started...
Have you considered using a raft? I'd imagine that river running on a cycle tour would be rather exciting!
Check out: Alpaca Rafts (http://www.alpackaraft.com/index.cfm?section=tips-and-technique&page=Choosing-and-Outfitting-Your-Raft&viewpost=2&ContentId=2640)
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