External sewerage networks are located outside residential premises. The system is designed to drain Wastewater and their further purification. Installation of an external sewer system is strictly regulated by regulations - SNiPs.

Classification of external sewer networks

External sewer networks, depending on the method of their organization, are divided into several types:

• systems where household wastewater and rain or melt water are transported separately and to different collectors are called separate;
• networks where rainwater and household wastewater is transported separately, but enters a common collector and is called semi-separate;
• systems without dividing water into domestic and rainwater are called all-floating.

The most effective, from an environmental point of view, is a separate sewer system. It is more expedient to install the same sewer system for domestic needs on a personal plot.

Main elements of external sewer networks

The external sewer network is complex design. As a rule, it includes:

• metal or polyethylene pipelines of various diameters intended for the passage of liquid;

• for various purposes: for viewing, for rotating the system, for arranging level differences. In most cases, reinforced concrete is used for devices, but durable plastics can also be used;

• collectors, which are large-diameter pipes into which water flows from the storm sewer network or domestic systems;
• specialized . Installed in places where it is impossible to equip the passage of liquid by gravity;

• various local types intended for primary wastewater treatment;

• discharges of water into external sewer networks or into bodies of water, for example, ponds.

Do-it-yourself installation of domestic external sewerage

Installing sewerage: external networks and structures is quite simple if you adhere to the basic rules:

• trenches dug for should contain a slope sufficient for gravity flow of liquid. If you do not comply with these standards, you will need to install additional pumping stations, which will complicate the work and negatively affect the cost of the system.
• Before installing the pipeline, the necessary equipment is installed: local treatment systems, wells provided for by the project.
• on a long straight section of the pipeline, the distance from one well to another should be at least 15 - 18 meters.
• It is more convenient to start installing the pipeline from the last outlet pipe.
• It is more expedient to connect pipes by welding into a socket.

If the above rules are observed, the sewer system will work flawlessly for a long time.

Sewerage project

Like many other types of construction work, installation of an external sewer network begins with a project. It is best to entrust such work to specialists, but you can develop it yourself.

At the first stage of design, it is necessary to establish where wastewater will flow in the future. It can be:

• centralized external sewer network. To connect to this system, it is necessary to carry out work to collect the documentation established by law. This connection is considered the best;
• special sealed wastewater storage tank. Such a system is periodically cleaned by machines, so it is advisable to install the tank closer to the fence and roadway for ease of access by equipment;
• local treatment facilities for further use of water, for example, for watering a garden or for discharging treated water into the nearest body of water.

At the next stage, it is necessary to study the climatic conditions of the area in which the external sewage system is supposed to be located:

• find out the depth of freezing of the ground, on which the depth of the network depends. If it is not possible to lay pipes and structures below the freezing layer, then you will need to purchase special insulation for pipes, for example, glass wool.

• examine the terrain. Is it possible to install gravity sewerage on the site or will the use of pumping stations be required?
• find out the type of soil and the level of groundwater. If the water is located close to the surface, then the possibility of laying pipes below the freezing depth is completely excluded. The type of soil affects the layer of protective cushion for the pipes, which is constructed from sand. If the site has heavy soils, then the protective layer should be larger.

At the last stage, some indicators necessary for the correct operation of the sewer network are calculated:

• amount of wastewater. It is estimated that one person needs about 200 liters of water per day.
• pipeline laying slope. According to SNiP requirements, for pipes with a diameter of no more than 200 mm, it is enough to make a slope of 2 cm for every 2 m of the pipeline.
• the required volume of a septic tank for an autonomous sewage system. The average course of wastewater disinfection occurs within 3 days.

It is better to entrust the design of external sewerage to specialists. As a last resort, you can carry out design work yourself, strictly following the recommendations.

Sewage installation

Installing a sewer system is somewhat easier than designing it. You can do this work yourself. For this:

1. trenches are dug for pipelines and designated structures. The minimum margin in dimensions should be at least 20 cm, which is necessary for the convenience of laying the network.

1. A layer of sand is placed at the bottom of all trenches.
2. structures are installed: pumps, wastewater treatment plants, wells and so on.
3. An external sewerage network is being installed.

1. pipelines are laid in trenches and covered with a layer of sand.

1. The soil is laid using the backfill method.

An external sewer network is necessary on a personal plot. This system of structures will help preserve the environment. environment and without additional effort obtain water for watering garden plants.

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External sewer networks.

IN Lately There is a massive construction of suburban housing, which is not surprising. People do not want to breathe polluted air and choose country life. But living conditions outside the city are radically different from those in the city, where there is hot, cold water and sewerage. Therefore, homeowners try to equip their homes with all possible communications in order to get as close to urban comfort as possible. Moreover, among other tasks, there must be the installation of internal sewerage, external networks and structures.

Types of sewerage

Depending on where the plumbing fixtures are located in the house, the type of sewer system is selected:

• gravity
• pressure

In the first case, wastewater is discharged from the house through external pipes into a septic tank or cesspool in a natural way - by gravity. This is possible if all plumbing fixtures in the house are installed above the outlet pipe.

But there are situations when bathhouses, swimming pools, baths and similar structures are installed in the basement or basement of a building. And in this case, a pressure sewer is required that removes wastewater using a pump.

In addition, the lead household waste divided into:

1. general alloy
2. separate
3. semi-separated

The all-alloy sewer system is designed to collect all wastewater - both domestic and rainwater - into a single sewer network and then discharge it into a collector or septic tank, and then outside the site.

A separate network involves the installation of separate collectors or septic tanks for domestic wastewater and rainwater.

The semi-separate system works on the principle of collecting household and rain waste into different pipelines connected in one collector.

Why is a pressure sewer better than a gravity sewer?

When removing wastewater using pumps, a number of positive effects are observed:

• The risk of blockages is eliminated, since the equipment is equipped with a cutting mechanism that crushes solid household waste.
• You can install pipes of smaller diameter, which allows you to save on construction costs.
• Such systems are more durable, since they can use both cast iron pipes and plastic ones, which are highly durable.
• Quick installation.
• Low cost of the sewer system.
• Small volume of excavation work.
• Pumping equipment does not require large areas and can easily be located in the basement of a house.

Sewer design

If the installation of a gravity sewer can be done without a project, “by eye,” then in the case of pressure networks, an engineering calculation is required.

The design of the sewerage system is carried out in conjunction with the design of the house. However, it depends on many factors:

• From the layout of the interior spaces.
• Soil type.
• Groundwater level.
• Depth of soil freezing in the winter months.
• On the number of sanitary and household appliances in the house.
• Depending on the number of people permanently residing in the house.
• If plumbing fixtures are installed at a considerable distance from each other, then, most likely, you will have to make two sewer exits from the building. Moreover, they can be directed to one collector or two.

When installing external networks, sewerage standards SNiP 3.05.04-85 must be observed. Therefore, it is best to entrust the preparation of the project to specialists. After all, they know all the nuances of constructing sewer networks - both gravity and pressure. In addition, they will intelligently link them with the water supply. Therefore, a project drawn up by professionals will ensure long-term effective work the entire wastewater disposal and disposal system.

Components of the sewer network

Internal sewerage

Regardless of what type of wastewater disposal is used - a gravity or pressure system - each consists of an internal and external part.

Internal sewerage includes:

• Sanitary fixtures - bath, toilet, kitchen sink, washbasin, urinals and bidet.
• Household appliances that use water - washing machines and dishwashers.
• Pipes.
• Various elements for connecting plumbing fixtures - elbows, elbows, tees.
• Sewer riser.

The external system consists of the following elements:

• A pipeline that carries wastewater from a home to a sewer or septic tank.
• Treatment facilities - cesspools, septic tanks, biological treatment stations.
• Drainage well.
• Aeration field.
• Inspection wells.
• Fan pipe.

As a rule, when building a country house, treatment facilities are arranged individually for each house, because they use gravity systems.

Note! A pressure sewer can connect several private houses or even an entire village.

Pipes for external networks

Pipes for external sewerage

For the installation of internal and external sewerage networks, pipes made of various materials are used:

• cast iron
• polyvinyl chloride
• polyethylene

Recently, cast iron pipes have been used less and less due to their high weight, high cost and susceptibility to corrosion. The polymers from which modern products are made for installing water supply and sewerage systems are characterized by high technical characteristics, among which:

• durability
• absence of corrosion processes
• a light weight
• easy installation
• low cost
• resistance to aggressive environments, which is typical for sewage

The ease of installation of sewerage systems lies in the fact that each pipe has a socket on one side, and on the other, an annular bulge that is inserted into the socket. The tightness of the connection is ensured by the presence of a rubber O-ring.

Despite the widespread popularity of plastic pipes, cast iron products are not yet losing their positions and are also used in laying sewer lines. They can usually be seen in areas where plastic products cannot be used.

Treatment plants

System with treatment plant Leader

The following are used as treatment facilities:

• cesspools - the simplest way collection of household waste and sewage
• septic tanks
• deep biological treatment stations

A cesspool is suitable for those houses where sewerage is used periodically - for example, for a summer residence. Where people live permanently, it is better to install septic tanks. In them, wastewater treatment occurs in 2 or 3 chambers, and the discharged purified water does not harm the surrounding landscape and soil.

If wastewater treatment in septic tanks reaches 75-80%, then biological stations They provide wastewater purified to 90-95%. After all, the sewage products in them, in addition to simple sludge, decompose with the help of various microorganisms. In addition, such devices are equipped with control sensors, which greatly facilitates their use.

The choice of treatment plant depends on several factors:

1. average daily volume of water consumed
2. type of soil on the site
3. type of sewerage - gravity or pressure
4. soil freezing depth
5. groundwater level
6. distances to the place of discharge of treated wastewater
7. discharge conditions - drainage well or aeration field

Features of installation of treatment facilities

Installation of an external highway

You can build septic tanks with your own hands, or you can install a factory-made product. But in any case, SNiP regulates the installation of external sewerage networks taking into account sanitary standards and rules. In this case, permissible distances to sources are determined drinking water and residential buildings.

Important! When the groundwater level is high on the site, and the installation of an aeration field is impossible, the optimal solution would be a storage septic tank.

It is a container with a neck from which a sewage disposal machine periodically pumps out sewage.

In all other cases, it is cheaper and easier to install septic tanks with several purification chambers and discharge of purified water into a drainage well or onto an aeration field. At the same time, you will have to call special equipment to pump out wastewater much less often - only to remove bottom sediment.

When using pressure sewerage, wastewater is removed from the house using pumps or sewerage stations. They can be installed both inside the house and outside.

Biological treatment systems

Intra-house pressure sewerage includes a pump, a solid waste grinding mechanism and a storage tank. They are installed in basements due to the noise produced by the pump and possible unpleasant odors from the storage device.

An outdoor station can provide drainage from several buildings at the same time. But initially they are all collected in one container, from where they are pumped to the main treatment facility. Here they are completely cleaned and further discharged.

Regardless of the chosen system, you should always be guided by SNiP for external sewerage. This document sets out all the requirements for the construction of septic tanks and other elements of the system.

Conclusion

Comfortable life outside the city will actually be such if the installation of all life support systems - water supply and sewerage - is carried out in accordance with building codes and regulations. A well-designed autonomous system for the collection and disposal of household waste and human waste products is the primary task of every homeowner. After all, it helps not only to enjoy all the benefits of civilization, but also to preserve the nature around us.

To avoid problems with the sewer system of a country house, when laying its street part it is necessary to comply with a number of sanitary and construction standards. Installation work can be entrusted to professionals or done by yourself. If the second option is chosen, then before you begin installing an external sewer system, you should familiarize yourself with the advice of experienced plumbers, otherwise correcting the mistakes made will result in a considerable waste of money and nerves.

The entire sewer system of a private house is divided into internal and external parts. The intra-house component ensures the collection of wastewater from plumbing fixtures and its supply to a single riser, which is connected to the street part of the drainage system.

General sewerage diagram for a private house

The main task of external sewerage networks is to transport wastewater to the disposal site and the disposal itself (in the case of an autonomous septic tank). They consist of pipelines and treatment facilities.

You can get rid of collected waste by:

• connections to a centralized system (if there is one);
• arrangement of an individual septic tank or cesspool.

In the first case, it is enough to lay pipes and equip sewer well. And in the second, in addition to installing external sewer networks, you will need to install a local cleaning system.

Important! According to sanitary standards, wastewater must be disposed of in such a way that it does not pollute aquifers and the surrounding area. Failure to comply with these requirements may result in significant fines.

Diagram of connecting the cottage to the centralized sewer network

For a private home, one of four methods of individual wastewater treatment is suitable:

1. A cesspool is inexpensive, but not very convenient.
2. Septic tank storage tank - you will have to constantly invite sewer trucks.
3. A two-chamber septic tank with post-treatment - in the first chamber, heavy fractions settle, and in the second, purified water is discharged into the ground.
4. Biological treatment station – special microorganisms are used to decompose sewage.

The first option is the cheapest, and the last is the most expensive. But in any case, an external sewerage pipeline will have to be laid to them.

Design and selection of materials

Regulatory requirements

Before you begin installing an external sewer system yourself, you need to prepare its design. There are certain requirements for the laying of pipes and the location of the septic tank.

When developing a project you will have to take into account:

• relief of the local area;
• distance to drinking wells and reservoirs;
• general climatic conditions;
• number of people living in the cottage (average daily volume of wastewater);
• soil characteristics (composition, groundwater level, freezing depth);
• technical conditions for connecting to a centralized system or the need to organize access for sewage disposal equipment for pumping out sewage.

All these requirements are specified in the codes of practice “Sewerage. External networks..." (SP 32.13330.2012) and "Single-apartment residential houses..." (SP 55.13330.2011), which replaced the SNiPs of the same name.

During installation autonomous system cleaning, you won’t have to collect a bunch of permits and then pay for utilities. But you will constantly need to monitor the condition of your septic tank and, if necessary, call the sewers.

Important! The entire sewerage system of a private house is built on the principle of gravity flow of wastewater. Installation of horizontal sections of sewer pipes outside the cottage should be carried out with a slope towards the treatment system.

Optimal slope for street sewer pipes

A slight slope of the pipeline ensures gravity flow of sewage. Do not tilt it too much, this can lead to blockages of solid fractions at the entrance to the sump. The optimal slope largely depends on the diameter of the pipe:

1. D500 mm – slope 30 mm/linear meter.
2. D1000–1100 mm – slope 20 mm/linear meter.
3. D1600 mm – slope 8 mm/linear meter.

Errors made during the design and installation of external sewer networks will lead not only to constantly forming blockages, but also to the poisoning of drinking water sources with fecal waste. Therefore, it is so important to follow SNiPs at all stages of sewerage creation.

What kind of pipes are used for external mains?

When installing external sewerage, building regulations allow the use of pipes from:

• become;
• cast iron;
• asbestos cement;
• polymers;
• ceramics.

Steel pipes are susceptible to corrosion and are rarely used. Cast iron is a classic, but due to its internal roughness, pipelines made from it are prone to silting. They are gradually being replaced by other materials.

Asbestos cement is cheap and non-corrosive, but is inferior in durability to high-quality plastic. Ceramic products have the greatest resource of strength and reliability, but they are also the most expensive. The optimal choice based on a combination of parameters is plastic.

Plastic pipes are easily connected using the joining method

Plastic pipes for external network sewers can be:

1. Polyvinyl chloride (PVC).
2. Polypropylene (PP).
3. Low pressure polyethylene (HDPE).

All of them are suitable for laying a sewer pipeline outside a private house. To install them, you can use special glue or cold welding technology. But it is much easier to select products with a socket at the end, and mount the main line by inserting one pipe into another.

Advice! PVC pipes may crack at temperatures below -15 C. They must be carefully insulated.

Technology for installing a house sewer network

In a private house, the installation of external sewerage usually begins after the walls and roof have been erected. To do this, a trench is dug to the septic tank, and pipes are laid there.

Limits of soil freezing depths in Russia

The depth of installation depends on the level of soil freezing on the plot. To prevent the sewer pipe from freezing, during installation it must be placed below the freezing point of the soil. It is different for each area.

In “cold” areas, instead of digging deep trenches, the sewer line is insulated. For this purpose, moisture-resistant insulation and/or heating cables are used.

Heating cable fastening technology

The laying of the external sewer network is as follows:

1. A trench is dug from the house to the septic tank, and a sand cushion 10–15 cm thick is compacted at its bottom.
2. The pipeline is laid with a slope away from the building.
3. The pipe is insulated and the heating cable is installed.
4. The trench is being backfilled.

Important! The sewer pipe laid in the trench should not have any sagging. Before backfilling, you must make sure of this, otherwise clogging will occur.

Often a pedestrian path or parking lot is built on top of a sewer pipe. In this case, the installation of external sewerage is carried out in a “case”. If mechanical load is periodically placed on the ground above the pipeline, the pipe must be protected. The figure below shows one of the options for such a case.

Sewer pipe in a case

The pipe (7) is wrapped with support rings (6), sealant (3 and 4) and closed with a case (5). At its ends, docking units are formed from clamps (1) and cuffs (2). Only such protection can guarantee the durability of the sewer pipeline.

And lastly, upon completion of installation work and before filling the pipeline with soil, it must be tested. A test run of water will allow you to check the tightness of the structure and correct installation.

Video: laying sewer pipes for a country house

The design and installation of external networks of the sewer system of a private house is strictly regulated by building codes. If these rules are grossly violated, both problems with the operation of the sewer system and negative impacts on nature. WITH installation work Even a beginner can handle it. But when preparing a project, it is better to consult with a competent engineer.

Correctly completed design and installation of external sewerage networks determines the duration and quality of their operation. The basic provisions and rules for the construction and repair of an external sewer network are determined by SNiP 2.04.03-85. The document regulates the full cycle of work on the installation of an engineering system from pipeline installation to construction of treatment facilities. SNiP sewerage external networks and structures will help you select the optimal material and build effective system disposal of wastewater and rainwater.

What is external sewerage

External sewerage includes branched pipelines and system elements necessary for transporting wastewater from residential buildings and other facilities to treatment facilities. The design of the utility network is carried out simultaneously with the preparation of water supply plans. The systems are interconnected by the need to maintain a balance between water consumption and disposal. Installation and maintenance of urban external sewerage is the responsibility of public utilities. Maintenance of autonomous sewage systems in private houses is carried out by the owners themselves.

There are two ways to transport wastewater:

• non-pressure or gravity;
• pressure, requiring the installation of pumping equipment.

Types of sewerage

To ensure the safe operation of external sewage systems, SNiP offers several methods:

• duplication of communications - providing the ability in case of an emergency to switch the flow to a parallel pipeline or channel;
• reliable power supply, availability of an alternative (backup) source;
• allowing for reserve when designing network capacity

Attention. When installing sewerage structures, a certain sanitary zone must be observed to the construction sites of residential and public buildings.

Structural diagrams

According to SNiP, external sewerage is divided into several systems according to the installation method:

• All-alloy - according to this installation scheme, all wastewater - domestic, storm, melt - is directed into one sewer collector or container.
• Separate - the system is designed so that household wastewater and melt (rain) water are transported through different pipelines and end up in various treatment facilities or storage tanks.
• Semi-separate wastewater and storm sewer are sent through different mains into one container.

All-alloy scheme

Attention. It is prohibited to discharge wastewater into water bodies that has not been treated to established standards.

Classification of sewer system

External engineering communications are installed in various places and have their own purpose.

Yard network – used to serve one building. It consists of the following elements: small diameter pipes (150 mm), building outlets, intake and inspection wells. This concept is used for a system connected to a central sewer system; it is not used for an autonomous system.

Yard network

Intra-block network - the network is arranged inside the block, it consists of the same elements as the yard network.

The street network is designed to transport wastewater collected from all neighborhoods. Such a pipeline is called a collector; its function is to collect wastewater and discharge it to a pumping station or treatment plant.

Attention. Ground laying of sewer pipelines in populated areas is not permitted.

Schemes of drainage networks

Depending on the characteristics of the terrain, one of the external drainage schemes is selected:

• perpendicular - used for rainwater sewer collectors to quickly transport water to the general flow;
• zone - a rare option, applied to objects with a significant difference in height; a pump is installed in the lower collector;
• cross-section - the main collector is installed along a river or other body of water to intercept wastewater;
• radial - wastewater is directed to various treatment facilities.

Components of an external sewer system

The utility network consists of several main parts:

1. Pipeline is a pipeline made of pipes of various lengths and diameters, laid with a slope.
2. Wells - structures vary in purpose, they are: drainage, inspection, differential and rotary. The wells are equipped with brackets for lowering repairmen and hatches with covers.
   
   Pipeline and well
3. Outlets into water receivers are elements that ensure the free exit of wastewater from the pipeline into the reservoir.
4. Collectors are underground tunnels in the form of large-diameter pipes (from 2000 mm), through which wastewater is transported to the end point of the network.
   
   Collector
5. Local treatment facilities are installations used for treating and discharging wastewater into water bodies. These include septic tanks, biological treatment stations and other equipment. The number of houses served depends on the size and capacity of the structure.
6. Pumping stations - installed at individual facilities that require a dosed supply of wastewater.

The choice of method for disposing of domestic and rainwater waste depends on a whole list of factors that are taken into account at the design stage:

• properties and nature of the soil;
• climatic features such as freezing depth;
• volume of transported wastewater;
• groundwater level;
• distance from the point of release from the building to the treatment plant.

Attention. The lowest permissible pipeline slope depends on the minimum sewer flow rate.

Selection of material for the pipeline

The materials used for the installation of lines and channels must be resistant to aggressive environments and the effects of abrasive particles contained in the liquid. To prevent gas corrosion of the upper part of the collector, ventilation is installed to prevent gas stagnation.

SNiP for external sewerage provides for the use of pipe networks made from the following materials for installation:

• polyethylene;
• polyvinyl chloride;
• polypropylene;
• steel;
• asbestos cement;
• cast iron;
• reinforced concrete.

Polymer pipes

Cast iron pipes

Reinforced concrete pipes

In rare cases, when installing a network, pipes made of ceramics and glass are used; such materials are allowed by the rules.

Polymer products are the optimal choice when installing external utility networks. They have all the qualities that ensure reliable and long-term operation of the system:

• resistance to mechanical stress;
• frost resistance;
• high throughput due to smooth surface;
• corrosion resistance;
• durability.

Rules for installing sewer networks

Pipe diameter

The capacity of the free-flow network depends on the size of the pipes. Building codes determine the minimum diameter of gravity pipes:

• street network – 200 mm;
• autonomous sewerage – 110-150 mm;
• intra-block – 150 mm;

The size of the rain and all-alloy street system is 250 mm, the intra-block system is 200 mm.

Speed

SNiP presents tables that determine the speed of movement of wastewater depending on the size of the pipeline or tray. These indicators help to avoid silting of sewer networks. The flow contains suspended particles, which, if the speed is insufficient, settle on the surface of the line.

Basic calculation data:

• diameter 150-250 mm – 0.7 m/s;
• 600-800 mm – 1 m/s;
• more than 1500 mm – 1.5 m/s.

The lowest speed of movement of clarified waste through trays and pipes is 0.4 m/s. Maximum wastewater transportation speed:

• through metal and plastic pipes – 8 m/s;
• for concrete and reinforced concrete – 4 m/s.

For rainwater drainage, the indicators are:

• metal and plastic pipes – 10 m/s;
• concrete and reinforced concrete – 7 m/s.

Pipeline slope

One of the basic rules when laying a pipeline is compliance with the slope norm. For systems where the fluid moves under the influence of gravitational forces, this parameter is critical. Negative consequences installation errors in the direction of decreasing or increasing the slope lead to improper functioning of the network, blockages and breakdowns.

Attention. The standard indicator is calculated per 1 linear meter of pipe.

For autonomous sewerage pipes that are smaller in size than central networks, the following standards apply:

In special conditions related to the terrain, a decrease in slope is allowed:

• pipes 150 mm up to 0.008;
• pipes 200 mm up to 0.007.

Storm water inlets are connected to the general system with a slope of 0.02.

Network depth

The minimum depth of the sewer pipeline depends on the thermal engineering calculation. The practice of operating utility networks in the area is also taken into account. The pipes are laid 0.3-0.5 m below the freezing point of the soil. The maximum depth depends on several factors:

• pipe material;
• type of soil;
• pipeline diameter;
• laying method.

Requirements for wells

Wells are an integral element of the sewer network, therefore the norms and rules for their installation are described in SNiP.

Manholes

To inspect the pipeline, special elements are installed - inspection wells. Their installation is carried out in two cases:

• at pipe joints;
• at the section where the direction of the pipeline changes.

SNiP determines the diameters of wells depending on the size of the pipes:

• main line up to 600 mm – well 1000 mm;
• pipeline from 700 mm and more - pipe size + 400 mm in length and 500 mm in width.

Inspection well

On straight sections of the gravity network, inspection structures are located every 35 m, for medium-diameter mains (500-600 mm) - 75 m, for large pipes (1500-2000 mm) - 200 m. The working part of the structure is equipped with a hanging ladder for descent.

Storm drain

Storm drainage serves to quickly drain rain and melt water. It can be open, closed or mixed. An open network consists of trays and channels, a closed network consists of stormwater inlets and an underground pipeline, a mixed network is a combination of pipes and trays. To reduce the length of the system, the discharge is carried out into the nearest body of water or ravine.

When installing rainwater drainage systems, it is necessary to provide for the installation of structures for cleaning the most contaminated wastewater generated during rainstorms. For this purpose, sand traps, settling tanks and filters are installed. It is also recommended to design the possibility of using purified rainwater for irrigation and industrial needs.

Wastewater treatment devices

BUILDING REGULATIONS

EXTERNAL NETWORKS AND STRUCTURES
WATER SUPPLY AND SEWERAGE

SNiP 3.05.04-85*

STATE CONSTRUCTION COMMITTEE OF THE USSR

Moscow 1990

DEVELOPED BY VODGEO Research Institute of the USSR State Construction Committee (candidate of technical sciences) IN AND. Gotovtsev- topic leader, VC. Andriadi), with the participation of the Soyuzvodokanalproekt of the USSR State Construction Committee ( P.G. Vasiliev And A.S. Ignatovich), Donetsk Industrial Construction Project of the USSR State Construction Committee ( S.A. Svetnitsky), NIIOSP named after. Gresevanov of the USSR State Construction Committee (candidate of technical sciences) V. G.Galitsky And DI. Fedorovich), Giprorechtrans of the Ministry of River Fleet of the RSFSR ( M.N.Domanevsky), Research Institute of Municipal Water Supply and Water Purification, AKH named after. K.D. Pamfilova of the Ministry of Housing and Communal Services of the RSFSR (Doctor of Technical Sciences) ON THE. Lukins, Ph.D. tech. sciences V.P. Kristul), Tula Promstroyproekt Institute of the USSR Ministry of Heavy Construction.

INTRODUCED BY THE VODGEO Research Institute of the USSR State Construction Committee.

PREPARED FOR APPROVAL BY Glavtekhnormirovanie Gosstroy USSR ( N.A. Shishov).

SNiP 3.05.04-85* is a reissue of SNiP 3.05.04-85 with amendment No. 1, approved by Decree of the USSR State Construction Committee dated May 25, 1990 No. 51.

The change was developed by the VNII VODGEO of the USSR State Construction Committee and TsNIIEP engineering equipment State Committee for Architecture.

Sections, paragraphs, tables to which changes have been made are marked with an asterisk.

Agreed with the Main Sanitary and Epidemiological Directorate of the USSR Ministry of Health by letter dated November 10, 1984 No. 121212/1600-14.

When using a regulatory document, one should take into account the approved changes to building codes and regulations and state standards published in the journal “Bulletin of Construction Equipment” of the USSR State Construction Committee and the information index “ State standards USSR" Gosstandart.

* These rules apply to the construction of new, expansion and reconstruction of existing external networks 1 and water supply and sewerage structures in populated areas of the national economy.

_________

1 External networks - in the following text “pipelines”.

1. GENERAL PROVISIONS

1.1. When constructing new, expanding and reconstructing existing pipelines and water supply and sewerage structures, in addition to the requirements of projects (working projects) 1 and these rules, the requirements of SNiP 3.01.01-85 *, SNiP 3.01.03-84, SNiP III-4-80 * must also be observed and other rules and regulations, standards and departmental regulatory documents approved in accordance with SNiP 1.01.01-83.

1 Projects (working projects) - in the following text “projects”.

1.2. Completed pipelines and water supply and sewerage structures should be put into operation in accordance with the requirements of SNiP 3.01.04-87.

2. EARTHWORK

2.1. Excavation and foundation work during the construction of pipelines and water supply and sewerage structures must be carried out in accordance with the requirements of SNiP 3.02.01-87.

3. INSTALLATION OF PIPELINES

GENERAL PROVISIONS

3.1. When moving pipes and assembled sections that have anti-corrosion coatings, soft pliers, flexible towels and other means should be used to prevent damage to these coatings.

3.2. When laying pipes intended for domestic and drinking water supply, surface water or waste water should not be allowed to enter them. Before installation, pipes and fittings, fittings and finished units must be inspected and cleaned inside and outside of dirt, snow, ice, oils and foreign objects.

3.3. Installation of pipelines must be carried out in accordance with the work project and technological maps after checking compliance with the design of the dimensions of the trench, fastening of the walls, bottom marks and, for above-ground installation, supporting structures. The results of the inspection must be reflected in the work log.

3.4. Socket type pipes gravity pipelines should, as a rule, be laid with a socket up the slope.

3.5. The straightness of sections of free-flow pipelines between adjacent wells provided for by the project should be controlled by viewing “into the light” using a mirror before and after backfilling the trench. When viewing a circular pipeline, the circle visible in the mirror must have the correct shape.

The permissible horizontal deviation from the circle shape should be no more than 1/4 of the pipeline diameter, but not more than 50 mm in each direction. Deviations from the correct vertical shape of the circle are not allowed.

3.6. The maximum deviations from the design position of the axes of pressure pipelines should not exceed ± 100 mm in plan, elevations of trays of non-pressure pipelines - ± 5 mm, and elevations of the top of pressure pipelines - ± 30 mm, unless other standards are justified by the design.

3.7. Laying pressure pipelines along a flat curve without the use of fittings is allowed for socket pipes with butt joints on rubber seals with a rotation angle at each joint of no more than 2° for pipes with a nominal diameter of up to 600 mm and no more than 1° for pipes with a nominal diameter over 600 mm.

3.8. When installing water supply and sewerage pipelines in mountainous conditions, in addition to the requirements of these rules, the requirements of Section. 9SNiP III-42-80.

3.9. When laying pipelines on a straight section of the route, the connected ends of adjacent pipes must be centered so that the width of the socket gap is the same along the entire circumference.

3.10. The ends of pipes, as well as holes in the flanges of shut-off and other fittings, should be closed with plugs or wooden plugs during breaks in installation.

3.11. Rubber seals for installation of pipelines in low temperatures outside air is not allowed to be used in a frozen state.

3.12. To seal (seal) butt joints of pipelines, sealing and “locking” materials, as well as sealants, should be used according to the project.

3.13. Flange connections of fittings and fittings should be installed in compliance with the following requirements:

flange connections must be installed perpendicular to the pipe axis;

the planes of the flanges being connected must be flat, the nuts of the bolts must be located on one side of the connection; The bolts should be tightened evenly in a cross pattern;

elimination of flange distortions by installing beveled gaskets or tightening bolts is not allowed;

Welding joints adjacent to the flange connection should be performed only after uniform tightening of all bolts on the flanges.

3.14. When using soil to construct a stop, the supporting wall of the pit must have an undisturbed soil structure.

3.15. The gap between the pipeline and the prefabricated part of the concrete or brick stops must be tightly filled with concrete mixture or cement mortar.

3.16. Protection of steel and reinforced concrete pipelines from corrosion should be carried out in accordance with the design and requirements of SNiP 3.04.03-85 and SNiP 2.03.11-85.

3.17. On pipelines under construction, the following stages and elements of hidden work are subject to acceptance with the drawing up of inspection reports for hidden work in the form given in VSNiP 3.01.01-85: preparation of the foundation for pipelines, installation of stops, size of gaps and sealing of butt joints, installation of wells and chambers, anti-corrosion protection of pipelines, sealing of places where pipelines pass through the walls of wells and chambers, backfilling of pipelines with a seal, etc.

STEEL PIPELINES

3.18. Welding methods, as well as types, structural elements and dimensions of welded joints of steel pipelines must comply with the requirements of GOST 16037-80.

3.19. Before assembling and welding pipes, you should clean them of dirt, check the geometric dimensions of the edges, clean the edges and the adjacent inner and outer surfaces of the pipes to a metallic shine to a width of at least 10 mm.

3.20. Upon completion of welding work, the external insulation of pipes at the welded joints must be restored in accordance with the design.

3.21. When assembling pipe joints without a backing ring, the displacement of the edges should not exceed 20% of the wall thickness, but not more than 3 mm. For butt joints assembled and welded on the remaining cylindrical ring, the displacement of the edges from the inside of the pipe should not exceed 1 mm.

3.22. The assembly of pipes with a diameter of over 100 mm, made with a longitudinal or spiral weld, should be carried out with an offset of the seams of adjacent pipes by at least 100 mm. When assembling a joint of pipes in which the factory longitudinal or spiral seam is welded on both sides, the displacement of these seams need not be made.

3.23. Transverse welded joints must be located at a distance of no less than:

0.2 m from the edge of the pipeline support structure;

0.3 m from the outer and inner surfaces of the chamber or the surface of the enclosing structure through which the pipeline passes, as well as from the edge of the case.

3.24. The connection of the ends of joined pipes and sections of pipelines when the gap between them is larger than the permissible value should be made by inserting a “coil” with a length of at least 200 mm.

3.25. The distance between the circumferential weld seam of the pipeline and the seam of the nozzles welded to the pipeline must be at least 100 mm.

3.26. The assembly of pipes for welding must be carried out using centralizers; It is allowed to straighten smooth dents at the ends of pipes with a depth of up to 3.5% of the pipe diameter and adjust the edges using jacks, roller bearings and other means. Sections of pipes with dents exceeding 3.5% of the pipe diameter or having tears should be cut out. The ends of pipes with nicks or chamfers with a depth of more than 5 mm should be cut off.

When applying a root weld, the tacks must be completely digested. The electrodes or welding wire used for tack welding must be of the same grade as that used for welding the main seam.

3.27. Welders are allowed to weld joints of steel pipelines if they have documents authorizing them to carry out welding work in accordance with the Rules for Certification of Welders approved by the USSR State Mining and Technical Supervision.

3.28. Before being allowed to work on welding pipeline joints, each welder must weld an acceptable joint under production conditions x (at the construction site) in the following cases:

if he started welding pipelines for the first time or had a break in work for more than 6 months;

if pipe welding is carried out from new grades of steel, using new grades of welding materials (electrodes, welding wire, fluxes) or using new types of welding equipment.

On pipes with a diameter of 529 mm or more, it is allowed to weld half of the permissible joint. The permissible joint is subjected to:

external inspection, during which the weld must meet the requirements of this section and GOST 16037-80;

radiographic control in accordance with the requirements of GOST 7512-82;

mechanical tensile and bending tests in accordance with GOST 6996-66.

In case of unsatisfactory results of checking a permissible joint, welding and re-inspection of two other permissible joints are performed. If, during repeated inspection, unsatisfactory results are obtained at at least one of the joints, the welder is recognized as having failed the tests and can be allowed to weld the pipeline only after additional training and repeated tests.

3.29. Each welder must have a mark assigned to him. The welder is obliged to knock out or deposit a mark at a distance of 30 - 50 mm from the joint on the side accessible for inspection.

3.30. Welding and tack welding of butt joints of pipes may be carried out at ambient temperatures down to minus 50° C. Moreover, welding work without heating the welded joints may be performed:

at outside air temperature to min. 20 ° C - when using pipes made of carbon steel with a carbon content of no more than 0.24% (regardless of the thickness of the pipe walls), as well as pipes made of low-alloy steel with a wall thickness of no more than 10 mm;

at outside air temperatures down to minus 10 °C - when using pipes made of carbon steel with a carbon content of over 0.24%, as well as pipes made of low-alloy steel with a wall thickness of over 10 mm. When the outside air temperature is below the above limits, welding work should be carried out with heating in special cabins, in which the air temperature should be maintained not lower than the above, or the ends of the welded pipes for a length of at least 200 mm should be heated in the open air to a temperature not lower 200 °C.

After welding is completed, it is necessary to ensure a gradual decrease in the temperature of the joints and adjacent pipe areas by covering them after welding with an asbestos towel or other method.

3.31. When multilayer welding, each layer of the seam must be cleared of slag and metal spatter before applying the next seam. Areas of weld metal with pores, cavities and cracks must be cut down to the base metal, and the weld craters must be welded.

3.32. When manual electric arc welding, individual layers of the seam must be applied so that their closing sections in adjacent layers do not coincide with one another.

3.33. When performing welding work outdoors during precipitation, the welding sites must be protected from moisture and wind.

3.34. When monitoring the quality of welded joints of steel pipelines, the following should be done:

operational control during the assembly and welding of the pipeline in accordance with the requirements SNiP 3.01.01-85 *;

checking the continuity of welded joints with the identification of internal defects using one of the non-destructive (physical) control methods - radiographic (X-ray or gammagraphic) according to GOST 7512-82 or ultrasonic according to GOST 14782-86.

The use of the ultrasonic method is allowed only in combination with the radiographic method, which must be used to check at least 10% of the total number of joints subject to control.

3.35. During operational quality control of welded joints of steel pipelines, it is necessary to check compliance with the standards of structural elements and dimensions of welded joints, welding method, quality of welding materials, edge preparation, size of gaps, number of tack welds, as well as serviceability of welding equipment.

3.36. All welded joints are subject to external inspection. On pipelines with a diameter of 1020 mm and larger, welded joints welded without a backing ring are subject to external inspection and dimensional measurements from the outside and inside of the pipe, in other cases - only from the outside. Before inspection, the weld seam and adjacent pipe surfaces to a width of at least 20 mm (on both sides of the seam) must be cleaned of slag, splashes of molten metal, scale and other contaminants.

Based on the results of external inspection, the quality of the weld is considered satisfactory if the following is not detected:

cracks in the seam and adjacent area;

deviations from the permissible dimensions and shape of the seam;

undercuts, depressions between rollers, sagging, burns, unwelded craters and pores coming to the surface, lack of penetration or sagging at the root of the seam (when inspecting the joint from inside the pipe);

displacements of pipe edges exceeding the permissible dimensions.

Joints that do not meet the listed requirements are subject to correction or removal and re-control of their quality.

3.38. Welded joints for inspection by physical methods are selected in the presence of the customer’s representative, who records in the work log information about the joints selected for inspection (location, welder’s mark, etc.).

3.39. Physical control methods should be applied to 100% of welded joints of pipelines laid in sections of transitions under and above railway and tram tracks, through water barriers, under highways, in city sewers for communications when combined with other utilities. The length of controlled sections of pipelines at sections of transitions should be no less than the following dimensions:

For railways- the distance between the axes of the outer tracks and 40 m from them in each direction;

for highways - the width of the embankment at the bottom or the excavation at the top and 25 m from them in each direction;

for water barriers - within the boundaries of the underwater crossing determined by section. 6SNiP 2.05.06-85;

for other utility lines - the width of the structure being crossed, including its drainage lines near the structure, plus at least 4 m in each direction from the extreme boundaries of the structure being crossed.

3.40. Welds should be rejected if, upon inspection by physical control methods, cracks, unwelded craters, burns, fistulas, and also lack of penetration at the root of the weld made on the backing ring are detected.

When checking welds using the radiographic method, the following are considered acceptable defects:

pores and inclusions, the sizes of which do not exceed the maximum permissible according to GOST 23055-78 for class 7 welded joints;

lack of penetration, concavity and excess penetration at the root of a weld made by electric arc welding without a backing ring, the height (depth) of which does not exceed 10% of the nominal wall thickness, and the total length is 1/3 of the internal perimeter of the joint.

3.41. If unacceptable defects in welds are detected by physical control methods, these defects should be eliminated and the quality of a double number of welds should be re-tested compared to that specified in clause. If unacceptable defects are detected during re-inspection, all joints made by this welder must be inspected.

3.42. Areas of the weld with unacceptable defects are subject to correction by local sampling and subsequent welding (as a rule, without overwelding the entire welded joint), if the total length of the sampling after removing the defective areas does not exceed the total length specified in GOST 23055-78 for class 7.

Correction of defects in joints should be done by arc welding.

Undercuts should be corrected by surfacing thread beads no more than 2 - 3 mm high. Cracks less than 50 mm long are drilled at the ends, cut out, thoroughly cleaned and welded in several layers.

3.43. The results of checking the quality of welded joints of steel pipelines using physical control methods should be documented in a report (protocol).

CAST IRON PIPELINES

3.44. Installation of cast iron pipes produced in accordance with GOST 9583-75 should be carried out with sealing of socket joints with hemp resin or bituminized strand and device asbestos-cement lock, or only sealant, and pipes produced in accordance with TU 14-3-12 47-83, rubber cuffs supplied complete with pipes without a lock device.

Compound asbestos-cement mixtures for the lock device, as well as sealant, are determined by the project.

3.45. The size of the gap between the thrust surface of the socket and the end of the connected pipe (regardless of the joint sealing material) should be taken, mm, for pipes with a diameter of up to 300 mm - 5, over 300 mm - 8-10.

3.46. The dimensions of the sealing elements of the butt joint of cast iron pressure pipes must correspond to values ​​given V.

Table 1

	Embedment depth, mm
	when using hemp or sisal strands	when installing a lock	when using only sealants
100-150	25 (35)
200-250	40 (50)
400-600	50 (60)
800-1600	55 (65)
2400	70 (80)

3.53. Sealing of butt joints of seam free-flow reinforced concrete and concrete pipes with smooth ends should be carried out in accordance with the design.

3.54. The connection of reinforced concrete and concrete pipes with pipeline fittings and metal pipes should be carried out using steel inserts or reinforced concrete fittings manufactured according to the design.

CERAMIC PIPELINES

3.55. The size of the gap between the ends of the ceramic pipes being laid (regardless of the material used to seal the joints) should be taken, mm: for pipes with a diameter of up to 300 mm - 5 - 7, for larger diameters - 8 - 10.

3.56. Butt joints of pipelines made of ceramic pipes should be sealed with hemp or sisal bituminized strand with subsequent installation of a lock made of cement mortar grade B7, 5, asphalt (bitumen) mastic and polysulfide (thiokol) sealants, if other materials are not provided for by the project. The use of asphalt mastic is allowed when the temperature of the transported waste liquid is no more than 40 ° C and in the absence of bitumen solvents in it.

The main dimensions of the elements of the butt joint of ceramic pipes must correspond to the values ​​​​given in.

Table 3

3.57. The sealing of pipes in the walls of wells and chambers should ensure tightness of connections and water resistance of wells in wet soils.

PIPELINES MADE FROM PLASTIC PIPES*

3.58. The connection of pipes made of high-density polyethylene (HDPE) and low-density polyethylene (LDPE) with each other and with fittings should be carried out using a heated tool using the method of contact butt welding or socket welding. Welding pipes and fittings made of polyethylene of various types (HDPE and LDPE) together is not allowed.

3.5 9. For welding, you should use installations (devices) that ensure maintaining the parameters of technological modes in accordance with OST 6-19-505-79 and others regulatory and technical documentation approved in the established order.

3.60. Welders are allowed to weld pipelines made of LDPE and HDPE if they have documents authorizing them to carry out work on welding plastics.

3.61. Welding of LDPE and HDPE pipes can be carried out at an outside air temperature of at least minus 10° C. At a lower outside air temperature, welding should be done in insulated rooms.

When performing welding work, the welding site must be protected from exposure atmospheric precipitation and dust.

3.62. Connection of pipes from polyvinyl chloride(PVC) with each other and with the shaped parts should be carried out by gluing together (with the use of glue brand GI PK-127 in accordance with TU 6-05-251-95-79) and using rubber cuffs supplied complete with pipes.

3.63. Glued joints should not be subjected to mechanical stress for 15 minutes. Pipelines with adhesive joints should not be subjected to hydraulic tests within 24 hours.

3.64. Gluing work should be carried out at an outside temperature of 5 to 35 °C. The work place must be protected from exposure to precipitation and dust.

4. PIPELINE TRANSITIONS THROUGH NATURAL AND ARTIFICIAL OBSTACLES

4.1. Construction of crossings of pressure pipelines for water supply and sewerage through water barriers (rivers, lakes, reservoirs, canals), underwater pipelines to water intakes and sewerage outlets within the bed of reservoirs, as well as underground passages through ravines, roads (roads and railways, including metro lines and tram tracks) and city passages must be carried out by specialized organizations in accordance with the requirements SNiP 3.02.01-87,SNiP III-42-80(section 8) and this section.

4.2. Methods for laying pipeline crossings through natural and artificial barriers are determined by the project.

4.3. The laying of underground pipelines under roads should be carried out with constant surveying and geodetic control of the construction organization over compliance with the planned and altitude positions of the casings and pipelines provided for by the project.

4.4. Deviations of the axis of protective casings of transitions from the design position for gravity free-flow pipelines should not exceed:

vertically - 0.6% of the length of the case, provided that the design slope is ensured;

horizontally - 1% of the length of the case.

For pressure pipelines, these deviations should not exceed 1 and 1.5% of the length of the case, respectively.

5. WATER SUPPLY AND SEWERAGE STRUCTURES

STRUCTURES FOR SURFACE WATER INTAKE

5.1. The construction of structures for the intake of surface water from rivers, lakes, reservoirs and canals should, as a rule, be carried out by specialized construction and installation organizations in accordance with the project.

5.2. Before constructing the foundation for channel inlets, their alignment axes and temporary benchmark marks must be checked.

WATER INJECTION WELLS

5.3. In the process of drilling wells, all types of work and main indicators (penetration, diameter of the drilling tool, fastening and removing pipes from the well, cementation, measurements of water levels and other operations) should be reflected in the drilling log. In this case, the name of the rocks passed, color, density (strength), fracturing, granulometric composition of rocks, water content, the presence and size of a “plug” during the excavation of quicksand, the appeared and established water level of all encountered aquifers, absorption of the flushing fluid. The water level in wells during drilling should be measured before the start of each shift. In flowing wells, water levels should be measured by extending pipes or measuring water pressure.

5.4. During the drilling process, depending on the actual geological section, it is allowed, within the aquifer established by the project, for the drilling organization to adjust the well depth, diameters and planting depth of technical columns without changing the operational diameter of the well and without increasing the cost of work. Changes to the well design should not worsen its sanitary condition and productivity.

5.5. Samples should be taken one from each rock layer, and if the layer is homogeneous, every 10 m.

By agreement with the design organization, rock samples may not be taken from all wells.

5.6. Isolation of the exploited aquifer in a well from unused aquifers should be performed using the drilling method:

rotational - by annular and intertubular cementation of casing columns to the marks provided for by the project:

impact - by crushing and driving the casing into a layer of natural dense clay to a depth of at least 1 m or by performing under-shoe cementation by creating a cavern with an expander or an eccentric bit.

5.7. To ensure the project granulometric composition of the well filter backfill material, clay and sand fractions must be removed by washing, and before backfilling, the washed material should be disinfected.

5.8. Exposing the filter during its filling should be carried out by raising the casing column each time by 0.5 - 0.6 m after filling the well by 0.8 - 1 m in height. The upper limit of the sprinkling must be at least 5 m above the working part of the filter.

5.9. After completion of drilling and installation of a filter, water intake wells must be tested by pumping, carried out continuously for the time stipulated by the project.

Before pumping begins, the well must be cleared of sludge and pumped, as a rule, with an airlift. In fissured rock and gravel and pebble In aquiferous rocks, pumping should begin from the maximum design drop in the water level, and in sandy rocks - from the minimum design drop. The value of the minimum actual decrease in water level should be within 0.4 - 0.6 of the maximum actual one.

In case of forced stoppage of water pumping work, if the total time shutdown exceeds 10% of the total design time for one drop in water level, pumping water for this drop should be repeated. In the case of pumping from wells equipped with a filter with sprinkling, the amount of shrinkage of the sprinkling material should be measured during pumping once a day.

5.10. The flow rate (productivity) of wells should be determined by a measuring tank with a filling time of at least 45 s. It is allowed to determine the flow rate using weirs and water meters.

The water level in the well should be measured with an accuracy of 0.1% of the depth of the measured water level.

The flow rate and water levels in the well should be measured at least every 2 hours during the entire pumping time determined by the project.

Control measurements of the well depth should be made at the beginning and at the end of pumping in the presence of a customer representative.

5.11. During the pumping process, the drilling organization must measure the water temperature and take water samples in accordance with GOST 18963-73 and GOST 4979-49 and deliver them to the laboratory to test the water quality in accordance with GOST 2874-82.

The quality of cementation of all casing strings, as well as the location of the working part of the filter, should be checked using geophysical methods. Estuary self-outpouring At the end of drilling, wells must be equipped with a valve and a fitting for a pressure gauge.

5.12. Upon completion of drilling the water intake well and testing it by pumping out water, the top of the production pipe must be welded with a metal cap and have a threaded hole for a plug bolt to measure the water level. The design and drilling numbers of the well, the name of the drilling organization and the year of drilling must be marked on the pipe.

To operate a well, in accordance with the design, it must be equipped with instruments for measuring water levels and flow rate.

5.13. Upon completion of drilling and pumping testing of the water intake well, the drilling organization must hand it over to the customer in accordance with the requirements SNiP 3.01.04-87, as well as samples of passed rocks and documentation (passport), including:

geological-lithological section with well design, corrected according to geophysical research data;

acts for laying a well, installing a filter, cementing casing strings;

a summary logging diagram with the results of its interpretation, signed by the organization that performed the geophysical work;

log of observations of pumping water from a water well;

data on the results of chemical, bacteriological analyzes and organoleptic water indicators according to GOST 2874-82 and the conclusion of the sanitary and epidemiological service.

The documentation must be agreed upon with the design organization before delivery to the customer.

TANK STRUCTURES

5 .14. When installing concrete and reinforced concrete monolithic and prefabricated tank structures, in addition to the requirements of the project, the requirements of SNiP 3.03.01-87 and these rules should also be met.

5.15. Backfilling of soil into the cavities and sprinkling of capacitive structures must be done, as a rule, in a mechanized way after laying communications to the capacitive structures, carrying out a hydraulic test of the structures, eliminating identified defects, and waterproofing the walls and ceilings.

5.16. After all types of work are completed and the concrete reaches its design strength, a hydraulic test of the tank structures is carried out in accordance with the requirements.

5.17. Installation drainage and distribution systems of filter structures may be carried out after a hydraulic test of the structure’s container for leaks.

5.18. Round holes in pipes for the distribution of water and air, as well as for collecting water, should be drilled in accordance with the class indicated in the design.

Deviations from the designed width of slot holes in polyethylene pipes should not exceed 0.1 mm, and from the designed clear length of the slot ± 3 mm.

5.19. Deviations in the distances between the axes of the couplings of the caps in the distribution and outlet systems of filters should not exceed ± 4 mm, and in the marks of the top of the caps (along the cylindrical protrusions) - ± 2 mm from the design position.

5.20. Markings of the edges of spillways in structures for distribution and collection of water (gutters, trays, etc.) must correspond to the design and must be aligned with the water level.

When installing overflows with triangular cutouts, deviations of the marks of the bottom of the cutouts from the design ones should not exceed ± 3 mm.

5.21. There should be no shells or growths on the inner and outer surfaces of gutters and channels for collecting and distributing water, as well as for collecting sediment. The trays of gutters and channels must have a slope specified by the design in the direction of the movement of water (or sediment). The presence of areas with a reverse slope is not allowed.

5.22. Filter media can be placed in structures for water purification by filtration after hydraulic testing of the containers of these structures, washing and cleaning of the pipelines connected to them, individual testing of the operation of each of the distribution and collection systems, measuring and shut-off devices.

5.23. Materials of filter media placed in water treatment facilities, including biofilters, according to granulometric the composition must comply with the project or the requirements of SNiP 2.04.02-84 and SNiP 2.04.03-85.

5.24. The deviation of the layer thickness of each fraction of the filter media from the design value and the thickness of the entire media should not exceed ± 20 mm.

5.25. After completion of work on laying the loading of the drinking water supply filter structure, the structure must be washed and disinfected, the procedure for which is presented in the recommended one.

5.26. Installation of flammable structural elements of wooden sprinklers, water-catching gratings, air guides panels and partition fan cooling towers and spray pools should be carried out after completion of welding work.

6. ADDITIONAL REQUIREMENTS FOR THE CONSTRUCTION OF PIPELINES AND WATER SUPPLY AND SEWERAGE STRUCTURES IN SPECIAL NATURAL AND CLIMATIC CONDITIONS

6.1. When constructing pipelines and water supply and sewerage structures in special natural and climatic conditions, the requirements of the project and this section must be observed.

6.2. Temporary water supply pipelines, as a rule, must be laid on the ground surface in compliance with the requirements for laying permanent water supply pipelines.

6.3. The construction of pipelines and structures on permafrost soils should be carried out, as a rule, at negative outdoor temperatures while preserving the frozen foundation soils. In the case of construction of pipelines and structures at positive outside temperatures, the foundation soils should be kept frozen and not disturbed temperature and humidity mode established by the project.

Preparation of the foundation for pipelines and structures in ice-saturated soils should be carried out by thawing them to the design depth and compaction, as well as by replacing ice-saturated soils with thawed compacted soils in accordance with the design.

Movement of vehicles and construction machines in summer time must be carried out along roads and access roads constructed in accordance with the project.

6.4. The construction of pipelines and structures in seismic areas should be carried out in the same ways and methods as in normal construction conditions, but with the implementation of measures provided for by the project to ensure their seismic resistance. Joints of steel pipelines and fittings should be welded only using electric arc methods and the quality of welding should be checked using physical control methods to the extent of 100%.

When constructing reinforced concrete tank structures, pipelines, wells and chambers, cement mortars with plasticizing additives should be used in accordance with the design.

6.5. All work to ensure the seismic resistance of pipelines and structures performed during the construction process should be reflected in the work log and in the inspection reports of hidden work.

6.6. When backfilling the cavities of tank structures built in mined areas, the preservation of expansion joints should be ensured.

Gaps of expansion joints over their entire height (from the bottom of the foundations to the top above the foundation parts of structures) must be cleared of soil, construction waste, influxes of concrete, mortar and formwork waste.

Certificates of inspection of hidden work must document all major special work, including: installation of expansion joints, installation of sliding joints in foundation structures and expansion joints; anchoring and welding in places where hinge joints are installed; installation of pipes passing through the walls of wells, chambers, and tank structures.

6.7. Pipelines in swamps should be laid in a trench after water has been drained from it or in a trench flooded with water, provided that the necessary measures are taken in accordance with the design to prevent them from floating up.

The pipeline strands should be dragged along the trench or moved afloat with plugged ends.

Laying of pipelines on dams that have been completely filled with compaction must be carried out as in normal soil conditions.

6.8. When constructing pipelines on subsidence soils, pits for butt joints should be made by compacting the soil.

7. TESTING OF PIPELINES AND STRUCTURES

PRESSURE PIPES

7.1. If there is no indication in the project about the testing method, pressure pipelines are subject to testing for strength and tightness, as a rule, by hydraulic method. Depending on the climatic conditions in the construction area and in the absence of water, a pneumatic testing method can be used for pipelines with an internal design pressure Р р, not more than:

underground cast iron, asbestos-cement and concrete glands - 0.5 MPa (5 kgf/cm 2);

underground steel - 1.6 MPa (16 kgf/cm 2);

above-ground steel - 0.3 MPa (3 kgf/cm 2).

7.2. Testing of pressure pipelines of all classes must be carried out by a construction and installation organization, as a rule, in two stages:

first- preliminary testing for strength and tightness, carried out after filling the sinuses with soil tamping to half the vertical diameter and powdering the pipes in accordance with the requirements of SNiP 3.02.01-87 with butt joints left open for inspection; this test can be carried out without the participation of representatives of the customer and the operating organization with the drawing up of a report approved by the chief engineer of the construction organization;

second-Acceptance (final) testing for strength and tightness should be performed after the pipeline is completely backfilled with the participation of representatives of the customer and the operating organization with the drawing up of a report on the test results in the form of mandatory or.

Both stages of the test must be performed before installing hydrants, plungers, and safety valves, instead of which flange plugs should be installed during the test. Preliminary testing of pipelines that are accessible for inspection in working condition or are subject to immediate backfilling during the construction process (work in winter time, in cramped conditions), with appropriate justification in projects it is allowed not to carry out.

7.3. Pipelines of underwater crossings are subject to preliminary testing twice: on a slipway or platform after welding the pipes, but before applying anti-corrosion insulation to the welded joints, and secondly - after laying the pipeline in a trench in the design position, but before backfilling with soil.

The results of preliminary and acceptance tests must be documented in a mandatory form.

7.4. Pipelines laid at crossings through railways and roads of categories I and II are subject to preliminary testing after laying the working pipeline in a case (casing) before filling the interpipe space of the case cavity and before backfilling the working and receiving pits of the crossing.

7.5. The values ​​of internal design pressure Р Р and test pressure Р and for preliminary and acceptance testing of the pressure pipeline for strength must be determined by the project in accordance with the requirements of SNiP 2.04.02-84 and indicated in the working documentation.

The value of the test pressure for tightness P g for carrying out both preliminary and acceptance tests of the pressure pipeline must be equal to the value of the internal design pressure P p plus the value P taken in accordance with the upper limit of pressure measurement, the accuracy class and the pressure gauge scale division. In this case, the value P g should not exceed the value of the acceptance test pressure of the pipeline for strength P i.

7.6* Pipelines made of steel, cast iron, reinforced concrete and asbestos-cement pipes, regardless of the testing method, should be tested with a length of less than 1 km - at one time; for longer lengths - in sections of no more than 1 km. The length of the test sections of these pipelines during hydraulic testing is allowed to exceed 1 km, provided that the permissible flow rate of pumped water should be determined as for a section 1 km long.

Pipelines made of LDPE, HDPE and PVC pipes, regardless of the test method, should be tested at a length of no more than 0.5 km at a time, and for longer lengths - in sections of no more than 0.5 km. With appropriate justification, the project allows testing of the specified pipelines in one step for a length of up to 1 km, provided that the permissible flow rate of pumped water should be determined as for a section 0.5 km long.