Organization and guidance of crossings over water barriers. OBZhD

BASICS OF SAFE LIFE
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Organization and guidance of crossings over water barriers. Basics of safe life

Fundamentals of Safe Life Activities (OBZhD)

water barriers are one of those obstacles, the overcoming of which requires certain knowledge, skills and abilities. There are several technically complex, but relatively safe ways to build a crossing (for example, a hinged crossing). However, these methods imply the presence of special equipment and equipment (carabiners, ropes, clips, etc.). This equipment is not always available, so it is useful to know how to overcome water obstacles using improvised means.

It is unacceptable to cross the river on the move. Careful reconnaissance of the banks of the river is needed in both directions. It is better to stay for a few hours or a day than to put your life in danger.

In this section, we will consider some of the ways to cross simple water obstacles that do not require special equipment.

Crossing over water

Small rivers or streams can sometimes be overcome by jumping, using a pole as insurance: they put it in the middle of a water obstacle, lean on it and, pushing off, jump over to the opposite bank.

On shallow rivers, it is possible to cross over protruding stones. A necessary condition for this type of crossing is protruding stones located at a distance of a step or a small jump that can be made from a place. Before using this method, you need to make sure that the stones are stable - with the help of a pole. If the stones are unstable, wet or icy, then when passing through them there is a danger of falling into the river stream. In this case, this method of crossing should be replaced with a safer one.

Crossing on a log or tree the safest and most convenient.

It is used in cases where it is impossible to cross in another way, and at hand there is a log or tree of suitable size 2-4 meters longer than the riverbed. For the crossing, the narrowest place of the river with raised banks is chosen so that the water does not flood the crossing.

Throwing or fusing a tree, its root part - the butt - must be fixed. At the thin end of the log, a rope is fixed. When throwing the log, it is first lifted vertically upwards, and then, supporting it with ropes, it is carefully lowered above the stream.

For a safety support, a pole is used, which is placed against the current, or a long pole is used as a railing.

Crossing over natural debris. On the rivers flowing in the forest zone, there are often blockages from trees or logs blown down by the stream. They can be used to go to the other side, after checking the stability of the logs.

Crossing over luggage. This method of crossing is used on narrow, but fast and deep rivers and streams, fording through which is associated with a risk for those crossing. Several thin logs are laid through the obstacle, fastened together with improvised means. For insurance, strong poles are used, fixed on the banks or held by the participants. For a safety support, you can also use a 3-5-meter pole, which is placed upstream. When crossing to the opposite bank, the pole is transferred to the next ferryer.

When using this type of crossing, it is not necessary to use living trees as luggage - there are always enough fallen trees in the forest.

Crossing the snow bridges. Such bridges are usually formed in the fans of winter and spring avalanches into the river valleys. When organizing this method of crossing, it is necessary to check the strength of the snow bridge by probing with a pole. If the bridge is not strong, it is overcome by crawling.

In the highlands - above the forest zone - water barriers are easiest to overcome crossing the tongue of a glacier, from which, in fact, the river flows.

Crossing the river

The main conditions for a successful crossing of the river is the choice of a safe place for fording.

The external signs of a ford are the expansion of the river in its straight section, ripples on the surface of the water, reaches, shallows, rifts, numerous branches of the river, as well as paths and roads descending to the river. After choosing the place of the crossing, the speed of the current and the depth of the river are determined. Wading the river is recommended at the following depth:

if the flow velocity is up to 1 m/s - no more than 0,9 m;
flow velocity up to 2 m/s - no more than 0,7 m;
flow velocity up to 3 m/s - no more than 0,5 m.

With a river flow speed of more than 3-4 m/s, even with the same flow depth - 0,5 m - fording is dangerous, and you need to look for other places or use another way of crossing.

Crossing sites can be classified as impassable, impassable and passable.

impassable sections of the river are characterized by the inaccessibility of the approach to water: steep or steep slopes, canyons; heavily waterlogged, viscous banks and bottom of the river; pits, whirlpools; large width, depth or fast current - 3 m / s or more.

Impassable water areas are characterized by the following features: a wide floodplain of the river, a strong current (2-3 m/s), low swampy banks, adverse weather conditions (rain, snow).

passable rivers have a shallow depth and an average flow - up to 2 m / s.

Crossing place choose, paying attention to the following points:

the shallowest places are found in the widest regions of the river and, conversely, the greatest depth and speed of the current are found in its narrowings;
signs of shallow water can be wide stretches with an increased flow rate along the entire width of the river; places where the river is divided by islands into several branches; stones protruding above the water; islands across the entire width; aquatic vegetation;
in the daytime, in calm weather, the surface of the water over shallow places - spits, rifts - is more even and lighter than over deep ones, where it has a wavy appearance and a dark color;
small ripples on the surface of the water indicate shallow water;
areas with steep banks are usually deep.

Пcrossing with a pole it is used in a wide range of depth and speed of the river: from 2,5 m/s, at a depth to the waist, and up to 4 m/s, at a depth to the knee. This method is widely applicable in practice.

After choosing the place of the crossing, they begin to conduct reconnaissance. It is carried out by one person, with minimal insurance, which can be a strong pole (stick) 2-2,5 m long. First you need to make sure that in the event of an unexpected loss of stability and a fall, the person crossing into the water will not be blown away by the flow of water, that the impact force of the flow is small and will allow him to quickly restore stability. Wading is possible when the depth of the stream is not higher than the middle of the thigh. If there is a dangerous place near the crossing point downstream (a sharp narrowing of the stream, as a result of which the speed of its flow increases significantly, as well as a steep cliff or waterfall), then the crossing point should be moved 30-40 m upstream.

It is necessary to cross only in boots: this way there is less chance of injuring your feet on the stones at the bottom of the river. The person crossing begins to move obliquely towards the other bank - at an angle to the current, leaning on a pole placed upstream. In order to reduce the pressure of the flow, it is desirable to reduce the area of its influence, for which it is recommended to carry out the crossing in half a turn. It is necessary to go in small steps, slowly, feeling the bottom of the river. It is necessary to constantly have at least two points of support: leg - leg or pole - leg. When moving the pole, its lower end should not be raised high, much less completely removed from the water. Since when carrying the pole there is not sufficient stability of the person crossing in the stream, very often there is a need for immediate support on the pole. It is important to remember that a pole placed downstream is not a means of insurance.

In the event that crossing one at a time is fraught with dangers (for example, the depth of the river reaches the waist, and the current speed is 3 m / s), they are crossed in a line or wall (Fig. 37).

Organization and guidance of crossings over water barriers

Rice. 37. Crossing the wall: a - correct, b - incorrect position; F1, F2 - the forces of the impact of the flow on the crossing

When crossing with a wall, it must be borne in mind that the force of the impact of the flow on those crossing, depending on their relative position along the river, is not the same. The whole weight of the load is assumed by the one going upstream - he, cutting through the stream, plays the role of a kind of breakwater. Given this, the strongest participant in the movement is placed upstream.

The main requirements for the following: do not run ahead, do not lag behind, strictly maintain the position of the wall parallel to the flow axis, in no case increase the "cross section" of the crossing group. If these conditions are not met, the wall will collapse and all participants will be in the water.

When crossing the wall, collective action is important. Based on the foregoing, there should be no more than four people crossing the wall.

The methods described above are quite sufficient for successfully fording passable rivers.

Basic rules for crossing water obstacles:

before the crossing, it is necessary to carefully reconnoiter the coast and assess the situation - taking into account the strength and speed of the flow, the depth and topography of the channel, the possibility of using supports;
it is necessary to determine the method of crossing;
it is important to choose the place and time of the crossing;
it is better to spend more time on reconnaissance, looking for a safe and convenient place to cross, than to take unnecessary risks by crossing in an inconvenient or dangerous place;
the more experienced should go first at the crossing;
when crossing with support on a pole, they should rest upstream;
it is necessary to cross the wade in shoes (in boots).

Authors: Aizman R.I., Krivoshchekov S.G.

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