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Water |
Hazards |
![[River Crossing]](../LogCross7.jpg)
River Crossing
Updated 7/12/97
(Last significant change was 7/12/97)
Introduction 
Occasionally, hikers may not be used to crossing streams or rivers in mountainous areas. This brief
guide provides background and suggestions to make the crossing successfully.
Water Body Types
Common water bodies in mountainous areas are rivers, streams, deep water, lakes, and ponds.
Swift and Wide Rivers
Mountainous snow melt floods the river channels for a few weeks until only glaciers (permanent snow) remain. In flood conditions, the rivers swell to deep, wide, torrents that should not be crossed. When only glacier melt and rain runoff remains, the river may be 70 feet across and only two feet deep. Since the river bottom slopes steeply, the flow rate is still some three feet per second.
Swift and Narrow Streams
Small side-hill streams, as opposed to valley rivers, are narrow, since they do not drain as much land area. In some cases, they can be jumped, but many contain large rocks that can serve as stepping stones. These riverlets are often spanned by a fallen log that can serve as a bridge.
Deep Water
Deep water is likely to float you off the bottom. If you can't firmly touch the bottom, you will likely float downstream. If the water is in a lake, you can usually walk around it. Crossing of deep water is not recommended, even in a still lake.
Ponds
Shallow ponds often have a deep mud bottom. Unlike streams and rivers, they are not scoured by spring or summer flood waters. The suction effect of the mud on your feet may make walking and wading extremely difficult. Ponds, like lakes, are best avoided.
Hazards
There are several hazards that may harm you or make a crossing simply unpleasant. Be aware and avoid them or reduce their probability.
Hypothermia
If you are exposed to cold water (perhaps 40 degrees Fahrenheit), your body will quickly lose heat to the water. The longer the exposure, the more heat will be lost. The cold can cause loss of feeling and control in your legs. If you should fall, full body immersion can be a serious emergency. If you fall, you may have to remove the wet clothing and dry off to recover heat. In severe cases, a warm, dry person can sacrifice body heat by lying next to you to warm you. (This isn't as much fun as you might think.)
Current Forces
The current force is proportional to the square of the water speed. In swift water, you may risk having your feet swept out from under you. Be aware of any rolling rocks driven by the current.
Turbulent Flow
Turbulent swirling water may conceal problems under the surface. There may be a hidden pool that is causing a strong swirl that should be avoided. A rough peak in the water often occurs over a deflecting obstruction under the surface.
Trap Points
While most rivers have a smooth gravel bottom, in rock shelf areas, there may be crevices that could trap or wedge a foot. A broken leg or ankle could result.
Floating Objects
While unlikely in nonflood periods, logs or branches could be floating downstream. Lookouts may be needed to watch upstream for these hazards.
Waterfalls
Avoid crossing just above a waterfall. That would not be a good place for you or your pack to be adrift.
Safe Crossing Techniques
General
The issues discussed above are in preparation for crossing water safely. A consideration of things that could go wrong helps you to be prepared for emergencies and well as to avoid them.
Preparation
The first thing is to assess what the water looks like. Is it flowing swiftly, slowly, not at all? Can you see the bottom, and is it smooth, rocky, or littered with water-soaked logs? Sizing up the hazards can help you avoid them or to react properly if you should slip. In cold water, even if only knee high, you must be determined to go completely across before stopping. I remember one stream in the Maroon Bells of Colorado that was so cold that I couldn't feel my feet. The air temperature was perhaps 80 degrees, but the water came from melting snowfields near the ridge of the valley.
The most important thing is to unfasten the waist strap of your pack. If necessary, you can get free of it while keeping a hand on a shoulder strap. All items to go with you must be contained in or strapped onto the pack. Carry nothing but a support stick in your hands. If you decide not to cross where you are, remember to go upstream to find a narrower place. There often may be a trail by the bank that others have used, but some are used only for fishing.
Supports and Aids
The obvious need is for side support to keep you upright. Strong sticks may often be found near the crossing. Test them beforehand, as they could be weak or rotten. Avoid putting a lot of pressure on the stick, but use it just to keep your balance.
Individuals
If you are traveling alone, you must be especially cautious. Without others to assist, you must ensure a safe crossing.
Group
Groups can assist each other by crossing by threes. A large person walks on the upstream side, while the other two walk in the shelter of the legs. Each holds on to another with one hand and uses a stick for stability.
This Web page was created by: Frank R. Leslie, who welcomes contributions and suggestions
For more info, email fleslie@palmnet.net
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Page last modified on
Friday, June 09, 2000 03:31 PM
Original material © 1997, by Frank R. Leslie
Original material © 1997, by Frank R. Leslie