Cutting down bushes for power lines, clearing agricultural land from agricultural lands, destroying and cutting down wild vegetation. Trimming trees in protected zones of overhead lines is a requirement of federal law Clearing trees from power lines

Occupational safety in construction. Part 2. Construction production.

The TTK is intended to familiarize workers and engineers with the rules for the production of work, as well as for the purpose of using it in the development of work production projects, construction organization projects, and other organizational and technological documentation.

2. GENERAL PROVISIONS

( PUE) . Chapter 2.5. Overhead power lines with voltages above 1 kV (Seventh Edition)
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Passage of overhead lines through plantings*

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* Plantings mean natural and artificial tree stands and shrubs, as well as gardens and parks.


2.5.206. As a rule, you should avoid laying overhead lines through forests of group I*.

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* The division of forests into groups is given in the Forest Code of the Russian Federation.


2.5.207. To allow overhead lines to pass through plantings, clearings must be cut.

The width of clearings in plantations should be taken depending on the height* of the plantations, taking into account their future growth within 25 years from the moment the overhead lines and forest group are put into operation.

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*Here and below, the height of the stand is understood as the average height of the dominant species in the upper tier of the stand, increased by 10%. In plantings of different ages, it means an increase of 10% in the average height of the dominant generation in terms of stock.


1. In plantations with a prospective rock height of up to 4 m, the width of the clearings is taken to be equal to the distance between the outermost wires of the overhead line plus 3 m in each direction from the outermost wires. When overhead lines pass through the territory of orchards, clearing of clearings is not necessary.

2. When passing overhead lines in forest plantations of group I, parks and orchards, the width of the clearing is calculated according to the formula

Where is the width of the clearing, m;

Horizontal distance between the outermost, most distant phase wires, m;

- the smallest permissible horizontal distance between the outermost wire of the overhead line and the crown of trees, m (these distances must be no less than those given in Table 2.5.21);

- horizontal projection of the sag of the wire and the supporting garland of insulators, m, at their greatest deviation in accordance with 2.5.73 (clause 1), taking into account the type of terrain in accordance with 2.5.6;

- radius of the horizontal projection of the crown, taking into account long-term growth within 25 years from the moment the overhead line is put into operation, m.

Table 2.5.21

The smallest horizontal distance between overhead line wires and tree crowns

For other tree species, the radii of crown projections are determined during specific design based on the data of the owner of the plantings.

3. In forests of groups II and III, the width of the clearing is taken equal to the larger of the two values ​​calculated using the formula given in paragraph 2 and the formula

Where is the height of the plantings taking into account future growth, m.

4. For VLZ, the width of clearings in plantings should be taken to be no less than the distance between the outermost wires plus 1.25 m in each direction, regardless of the height of the plantings. When passing overhead lines through the territory of orchards with trees more than 4 m high, the distance from the outermost wires to the trees must be at least 2 m.

5. Individual trees or groups of trees growing outside the clearing and threatening to fall on the wires or supports of the overhead line must be cut down.

2.5.208. In depressions of the relief, on slopes and in ravines, a clearing is cut taking into account the prospective height of the plantings, and if the vertical distance from the top of the tree crowns to the overhead line wire is more than 9 m, the clearing is cut only under the overhead line in width equal to the distance between the outermost wires plus 2 m in each direction.

After installation is completed, areas where slopes are broken in clearings should be planted with shrubs.

2.5.209. Along the entire width of the clearing along the overhead line route, it must be cleared of felled trees and shrubs, stumps must be uprooted or cut to ground level, and reclamation must be carried out.

SNiP 3.05.06-85 Electrical devices
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2.20. Before the start of electrical installation work on the construction of overhead power lines with voltages up to 1000 V and above, preparatory work must be carried out in accordance with SNiP 3.01.01-85*, including:
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*SNiP 3.01.01-85 is not valid. SNiP 01/12/2004 “Construction Organization” is in force. - Database manufacturer's note.


Inventory structures have been prepared in the locations of construction sites and temporary bases for storing materials and equipment; temporary access roads, bridges and installation sites were constructed;

clearings have been made;

The demolition of buildings envisaged by the project and the reconstruction of intersecting engineering structures located on or near the overhead line route and interfering with the work were carried out.

Cutting clearings

3.116. The clearing along the overhead line route must be cleared of felled trees and shrubs. Commercial timber and firewood must be stacked outside the clearing.

The distances from wires to green spaces and from the axis of the route to stacks of combustible materials must be indicated in the project. Cutting down bushes on loose soils, steep slopes and areas flooded during floods is not allowed.

3.117. Burning of branches and other logging residues should be carried out within the permitted period of time.

3.118. Wood left in stacks on the overhead line route for the fire-hazardous period, as well as the “shafts” of logging residues remaining during this period, must be bordered by a mineralized strip 1 m wide, from which grass vegetation, forest litter and other combustible materials must be completely removed down to the mineral soil layer. .

Rules for electrical installations ( PUE) . Chapter 2.4. Overhead power lines with voltage up to 1 kV (Seventh Edition)
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2.4.8. When passing overhead lines through forests and green spaces, cutting down clearings is not required. In this case, the distance from the wires to trees and bushes at the greatest sag of the SIP and their greatest deviation should be at least 0.3 m.

When passing overhead lines with bare wires through forests and green spaces, cutting down a clearing is not necessary. In this case, the distance from the wires at the greatest sag or greatest deviation to trees and bushes must be at least 1 m.

The distance from insulated wires to green spaces must be at least 0.5 m.

3. ORGANIZATION AND TECHNOLOGY OF WORK EXECUTION

The accepted cutting area for clearing construction is divided into sections according to the number of teams. Each team performs work in the following sequence in the cutting area allocated to it.

The fellers move first, followed by the limbers, and then the skidders.

To fell a tree in the desired direction, you must first cut or saw it on the side in which it will fall, and then saw it on the side opposite to the cut or cut. Hems are of the following types: normal or straight, simplified, oblique, miter, two parallel cuts.

Practice has established the following undercut dimensions: depth 1/4 (the diameter of the tree at the undercut location); the distance between the hem planes is 0.6-0.8.

For strongly inclined trees, the cut is made from the side of the slope of the tree, while the depth of the cut should be equal to 1/3, and the distance between the planes of the cut should be 0.8.

Trees are felled from the middle of the cutting area with the tops or butts in the direction of the skidding (depending on the type of skidding - with the tops or butts forward).

After completing the cut, they begin cutting down the tree. The cutting plane must be perpendicular to the axis of the tree.

The permissible bevel of the cut of trees used for the production of business assortments should not exceed 1/10 of the diameter of the sawn end.

The saw bar or hand saw blade should be positioned horizontally, since trees usually stand vertically; In some trees, the deviation of the axis from the vertical at the stump does not exceed an angle of 6°. The cutting plane should be at the height of the upper edge of the hem.

In mountainous conditions, on slopes up to 20° steep, the order of felling trees is the same as on the plain; on slopes steeper than 20°, simultaneous logging and skidding is not permitted.

On slopes with a steepness of more than 30°, trees are felled across the slope so that the stumps of trees cut down below prevent trees felled from rolling down.

On slopes up to 30° steep, in order to avoid blockage, simultaneous felling of no more than 10-15 small-branched trees or 4-5 large-branched trees is allowed.

To avoid blockage, trees in the upper row should be felled after the trees in the lower rows on the slope have been removed.

Municipalities in situations involving pruning trees and violating the integrity of green spaces refer to administrative offenses provided for in Part 1 of Art. 4.4 of the Regional Law of October 25, 2002 No. 273-ZS “On Administrative Offences”. However, it is not taken into account that there are also requirements of federal legislation that have supreme legal force in relation to regional regulations, that is, they are priority.
In the case of pruning tree crowns in protected zones of overhead power lines, energy workers comply with the requirements of the Government Resolution Russian Federation dated 24.02.2009 No. 160 “On the procedure for establishing security zones of electric grid facilities and special conditions for the use of land plots located within the boundaries of such zones.”
General terms and conditions the use of land plots in the power transmission line security zone is the use of such plots without seizure from the owners/possessors, but within their boundaries a special regime for their use may be introduced, limiting or prohibiting those types of activities that are incompatible with the purposes of establishing zones.
From paragraphs 21-23 of the Decree of the Government of the Russian Federation dated February 24, 2009 No. 160, it follows that in order to ensure trouble-free operation and operation of electric grid facilities in security zones, network organizations construct and maintain clearings along overhead power lines and along the perimeter of substations if the specified zones are located in green spaces, cutting down and filing of trees and shrubs within the minimum permissible distances to their crowns, as well as cutting down trees that threaten to fall. At the same time, network organizations are obliged to ensure the maintenance of the clearing in a fire-safe condition, maintaining the required width of the clearings in the sizes provided for by the legislation of the Russian Federation, by cutting down, pruning the crowns of trees (shrubs) and other means, to cut down or trim the crowns of trees growing in clearings whose height exceeds 4 meters.
Moreover, according to clause 10 of the Government of the Russian Federation of February 24, 2009 N 160, within the protective zones of overhead lines, any activities, including planting and cutting down trees and shrubs, are prohibited without written approval network organizations equally for legal entities and individuals.
The priority for power grid organizations is reliable power supply and safety for consumers. Taking into account the wishes of citizens about the aesthetic and environmental appearance of the city, power engineers carry out pruning of crowns according to the minimum possible requirements - the height should not exceed 4 meters, although the legislation allows for complete clearance of the security zones of overhead lines from vegetation. In addition, responsibility for the proper condition of green spaces and their care are the responsibility of the municipality (norms of the Rules for the protection of green spaces in the city of Rostov-on-Don, approved by the Decision of the Rostov-on-Don City Duma of February 21, 2012 N 239, in subparagraph 6 paragraph 2 of which defines the list of persons entrusted with the protection and maintenance of green spaces). The distribution network company always meets halfway and issues approval for these types of work and is ready to temporarily de-energize the line to ensure safety, but such requests from the municipality, unfortunately, are received infrequently.

For reference:
Why do you need tree pruning at all?! Trees under overhead power lines pose a threat to uninterrupted transmission electrical energy, and within the limits settlement the threat triples.
Firstly, when there is strong wind or heavy wet snow, branches bend or break off and fall onto the wires, causing short circuits or broken lines. Secondly, in the case of a strong wind, tree branches can connect wires of different phases, the resulting electric arc has a temperature of thousands of degrees, and then even a wet tree will flare up like a match. And thirdly, there is a high probability of electric shock to a person or a severe fire. When a tree grows to the level of electrical wires, they begin to interact. It is known that wood does not conduct electricity, but everything changes if it rains - a wet tree is no longer a dielectric and can conduct current to the ground or even to an unsuspecting person and this can lead to an irreparable tragedy.
Imagine that such a tree grows next to your house and how events could unfold in an unfavorable scenario.
And if the line is high-voltage, the safe distance to the wire can be measured in meters (!), since when a tree branch approaches the wire, a discharge can occur, which can also cause injury to a person standing under the tree and a fire. To avoid such troubles, employees network company clearing clearings along the route of overhead lines. In addition to pruning trees, it also includes the elimination of grass, shrubs, and reeds. Please note that our services only cut down branches that pose a threat, preserving the tree itself as much as possible.

Quite often, residents of the private sector, on whose property there are tall trees, have to deal with the fact that the crown of green spaces touches power lines. In case of strong wind or snowstorm, this is fraught with the short circuit of the wires, their breakage and the creation of an emergency situation. In addition, when a wire falls to the ground, there is a danger of electric shock to people passing nearby.

Electric grid companies, according to sanitary standards, are required to clear the area through which power lines pass. For power lines with voltage less than 1 kW, the size of the security zone is 2 meters, and for power lines 6; 10 kW – 10 meters. But network farms do not always cope with their responsibilities and private landowners have to take care of the condition of the trees on their property themselves.

Requirements for clearing power lines

Clearing power lines from trees without turning off the voltage is permitted if the height of the trunk does not exceed 4 meters, and the branches are located at a distance from the wires:

• 1 meter at power line voltage up to 1 kV;
• 2 meters at power line voltage from 6 to 35 kV.

In other cases, power lines must be de-energized.

Tree crown pruning and felling can be carried out both by employees of power grid organizations and by specialists from certified companies on a contractual basis. In the second option, everything is provided technical events, preventing people from being electrocuted and trees falling onto overhead lines.

Before starting work, the area is cleared and guy ropes are provided when the entire tree is felled. The forest is cut in parts and the crown is trimmed using hydraulic lifts or aerial platforms. Cut branches and fragments of the trunk are thrown to the ground, and in the presence of dense buildings they are lowered using a rope or cable.

Clearing power lines in St. Petersburg

The Travo-Kos company provides a full range of services for cleaning tree and shrub vegetation that threatens power lines. The work is carried out by workers (at least 2 people) with appropriate qualifications, third electrical safety group and permission to work at heights. They are equipped with working tools, ladders, and personal protection and special equipment with telescopic lifts.

After inspecting the customer’s territory, our company’s engineer selects the optimal method for felling trees and trimming the crown, which complies with the instructions for safe work when clearing power lines from green spaces.

Cost of clearing power lines