Preparation for crossing suspect ice
Crossing any frozen water is a risky business, but especially avoid ice which has water flowing beneath it. The depth of ice varies as the moving water washes against the underside and wears it away. A fall through ice about moving water is potentially very dangerous. It is very likely to result in death if you are swept beneath the ice. If you must cross river ice, look for a spot where the river is broad and flows in a straight course. Avoid sleep gradients where fast turbulent water is likely to occur.
When crossing suspect frozen water, ensure everything is ready to be ejected. Carry your rucksack on one arm, loosen ski bindings, take wrists out of the wrist loops of ski poles. If you go into the water you can then jettison anything which hinders your self rescue. The other alternative to carrying the equipment is to tow it behind you, so that if you do take a swim there will be dry gear waiting for you when you get out. Another benefit of towing equipment is that the total weight of you and your equipment is spread over a greater area and so there is less likelihood of a breakthrough. If possible, keep to hand a sharp instrument to be used as an ice-pick. If you go through the ice, finding hand holds to help you get out of the hole will be your greatest difficulty. The ice-pick will enable you to do this.
Only expose one person to danger at a time.
Extract from "Survival Advantage" by Andrew Lane
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