The process of planning and constructing sewer systems is not complicated, but there are special rules And regulations SNiP, which impose certain requirements for installation and materials. There are also special public services that check the device sewer well according to SNiP, and if violations are detected, they may impose a fine or require that the system be rebuilt.
Therefore, before building a sewer well with your own hands, you need to familiarize yourself with their main types and installation rules.
Types of sewer wells
By functional purpose mines are divided into several main types:
- examination rooms;
- differential;
- rotary;
- accumulative;
- filtration.
Each of these types performs its specific function.
Inspection well
An inspection well (photo) is a shaft that is located above the main drainage line. Such a shaft makes it possible to conduct a visual inspection of the system’s performance and, if necessary, flush it or mechanical cleaning during operation.
In most cases, such shafts are installed on straight sections of drainage at a certain distance, however, shafts installed at turns or intersections of communications can also be called inspection shafts.
Inspection shafts can be of several types:
- linear, installed on straight sections;
- rotary, installed in places where the direction of the highway changes. In order to avoid hydraulic resistance, the angle between the incoming and outgoing lines must be at least 90 degrees;
- nodal, installed at the junction of several highways. Such chambers connect one outlet pipe with several incoming pipes, but there can be no more than three incoming pipes;
- control, installed at connection points private system to the main one.
Note! The distance between inspection shafts is determined by the diameter of the pipe. For example, with a pipe diameter of 15 cm, the distance between wells is set to no more than 35 meters. With a pipe diameter of 50 - 70 cm, the distance between the shafts is 75 meters.
Drop well
The construction of a differential sewer well is a simple structure (see photo), which is installed in the following cases:
- when reducing the depth of the ditch under the drainage main;
- when bypassing other underground pipes or communications;
- to prevent high speed fluid movement.
According to the type of design and functions, drop wells are divided into several types:
- a conventional shaft with a liquid supply in the upper part and an outlet in the lower part;
- difference with the baffle-drain wall to reduce the flow rate;
- short channels with a large degree of slope to increase flow speed;
- a mine with multi-stage drops.
Rotary well
Such shafts are installed in those sections of the highway where sharp turns of the channel are necessary, since it is in these places that the system most often becomes clogged.
Storage well
Storage shafts or wells (photo) are designed for collecting and storing waste liquid with its subsequent pumping using a pump or special vacuum trucks.
For private houses, the installation of sewer wells of this type can be profitable solution, if the closest central system is far away or absent altogether. Depending on the volume, such shafts can be made of iron concrete rings, monolithic concrete or large plastic containers.
With a small amount of wastewater, installing a plastic tank is most justified, since the price of such a tank is low and the installation process can be done with your own hands, without the involvement of equipment or professional construction teams.
Filtration well
Filtration shafts or wells can be open or closed type. Both types of wells are designed to separate wastewater and separate large debris and heavy substances from the liquid.
Facilities open type They are shafts made of perforated concrete blocks, where liquid leaves through special holes into the ground, and heavy substances remain within the shaft and are subsequently removed by special equipment for burial or disposal.
Closed wells are sealed containers with technological outlets, which are located at different heights. As wastewater enters, floating particles are removed by the upper channels, sedimentary layers are removed by the lower ones.
All owners country houses sooner or later they begin to arrange life support systems. After all, it’s comfortable country life involves supplying residential buildings with everything necessary - heat, drinking water and, of course, the possibility of drainage or sewerage.
Sewerage autonomous type is quite complex engineering system, the installation of which requires certain plumbing and construction skills. One of essential elements any autonomous sewerage- special well. Moreover, the sewage system requires the construction of several wells at once - rotary, inspection, and also receiving household waste and rainwater. Understanding the structure and types of such wells will be useful for any zealous owner.
Which material to choose?
Builders prefer to construct wells from plastic or reinforced concrete - these are the most popular materials today.Of course, there are alternative ways arrangement of wells. For example, from old car tires. This is the most a budget option, but, unfortunately, not distinguished by reliability and tightness.
Plastic
easy to install and durable material. Manufacturers produce ready-made plastic models. You can also build a well from corrugated pipe and plastic plates. Such construction will cost slightly less, but will take more time (the work requires certain skills).
Main advantages:
- light weight;
- strength and reliability;
- the ability to replace the lower tray (section used to connect the pipeline);
- tightness of all elements (rubber seals are used);
- Possibility of ordering containers of individual sizes.
- high cost of models (about 4,000–11,000 rubles).
Also, plastic samples can have a one-piece design. The disadvantage of such models is the already specified depth of the pipeline. Collapsible models have universal installation properties - if desired, the depth can be increased or, conversely, decreased.
More often plastic wells used as rotating or viewing structures. However, the tightness allows the plastic container to be used as a water collector with subsequent pumping out of the liquid using a pump.
Reinforced concrete
Classic material for sewerage. Wells are built from concrete rings, followed by sealing all joints between the rings with cement and sealant. It's also quite functional.
Advantages: 
- versatility;
- long service life (more than 50 years);
- high installation speed;
- strength and reliability;
- affordable price.
Flaws:
- heavy weight;
- Installation requires a winch or special equipment.
Well construction
Any sewer well consists of three structural elements:
- sealed bottom;
- shafts of the required depth;
- upper ceiling equipped with a round or square hatch.
The reinforced concrete structure is constructed as follows: 
- A hole of the required depth is dug with a margin for free movement of the rings (approximately 10-20 cm). If the soil is loose and the well is deep (more than 1.5 meters), the recess is made inside the first ring.
- The bottom of the pit is filled with concrete. Using a perforator, technical holes are punched in the rings for pipeline installation. The pipes are fixed using cement mortar and sealant. If it is deep and intended for regular inspection of the sewer system, a metal ladder is mounted on its walls for ease of descent.
- The shaft is blocked from above concrete slab with a hole for a hatch. A special metal frame is inserted into the hole, and a cover is mounted on top. It can be installed on curtains and equipped with a lock. Or look like a cast iron hatch.
Plastic models include:
- lower tray with pipe connections;
- a shaft made of multilayer plastic;
- transition pipe telescopic design;
- frame and hatch made of cast iron.
All elements are connected to each other using rubber seals, ensuring complete tightness of the structure.
Main types of wells
Based on their area of application, wells are divided into several main types: 
- For regular inspection or inspection - structures are located in places shut-off valves and are intended for monitoring and maintenance of sewer systems.
- Rotary - a type of inspection wells. They are installed at pipeline bend points. The main purpose of such structures is quick access to the bend (elbow) of the pipe in order to clean it from contamination.
- Filtration facilities are special structures that lack tightness (having a perforated bottom). They serve for the accumulation of not very polluted wastewater with its subsequent filtration into the ground. This perfect solution for drainage of water from showers or adjoining rooms drainage systems. At the bottom of the well, a filter is made of fine crushed stone and sand (sometimes the shaft is filled with the same material). The filter thickness is at least 40-50 centimeters.
- Drops are structures designed to dampen or increase flow speed. They are installed in places where the pipeline sharply deepens or at the points of connection of deep-seated collectors to the main line. The design is based on a vertical pipe (the omission is a part in the form of a straight cross and an elbow). The well itself is arranged as a multi-stage structure or has the shape of a classic shaft.
- Serving for water storage or storage are sealed wells, the liquid from which is pumped out using a pump or flows through a signal pipe into the nearest ravine. To clean such a well, owners often hire vacuum cleaners. The regularity of cleaning directly depends on the capacity of the well. The more spacious it is, the less often you will have to resort to pumping out liquid. The average height of a well is two meters.
What wells are needed 
- Storage tanks are required exclusively for the construction of autonomous sewer systems.
- Drop-over structures are more often used when connecting home sewerage to the central city highway.
- Filtration structures can be used for wastewater clean water, does not contain harmful environment impurities. For example, for arranging storm drains, drainage from a shower stall or bathtub. Water from washing and dishwashers, containing aggressive detergents, you cannot filter into the ground!
- Rotary and viewing structures are arranged as in autonomous systems, and on pipelines connected to a public highway.
SNiP standards
The construction of any sewer well is regulated by special sanitary and technical standards, displayed in a special document known as SNiP.
This document requires certain preliminary work.
Necessary: 
- determine the location of the well and mark the area;
- uproot all trees and bushes that interfere with construction;
- equip construction site– ensure free access for equipment;
- draw up a plan (scheme) and coordinate it with neighbors and the city water utility.
Construction work also has strict regulations and includes: 
- preparation of the pit (pit);
- filling the bottom with crushed stone and sand;
- carrying out complete waterproofing of the bottom using concrete mortar;
- installation of concrete rings or plastic tank;
- laying pipes;
- sealing all pipes with cement mortar or bitumen (for concrete structures, holes around the supplied pipes are sealed);
- functionality check (testing for the possibility of leakage);
- backfilling the well from the outside (fine crushed stone and soil are used for plastic, clay for concrete);
- additional treatment of concrete structures with waterproofing materials.
Basic technical requirements:
- Observation structures are installed every 30-40 meters (diameter 15 cm) or 50 meters (diameter 20 cm).
- Rotary wells must be constructed at all pipeline bends and branch pipes.
- In all places where the pipe diameter changes or there is a sharp slope, drop wells are installed.
The installation of a drainage system involves the installation of a sewer well. This element of the treatment design plays a key role when carrying out repair work and preventative measures such as pumping, flushing and cleaning. The key to uninterrupted operation of the system is a competent calculation of the volume and depth of storage tanks and correct installation. Let's look at how to determine the height of a sewer well and calculate the volume of tanks.
- plastic;
- bricks;
- monolithic concrete;
- concrete rings;
By correctly choosing a tank of suitable size, the owner of the site saves himself from the problems associated with the operation of the structure
If you focus on the purpose of sewer tanks, then they come in several types.
Observation
Inspection wells are shafts equipped with a chamber inside, in the walls of which the inlet and outlet pipes are connected by arranging a special tray. They are designed to monitor the treatment plant.
The main difference between the design is that the collector and drainage pipe in it replace the open tray
Through inspection structures, free access to the pipeline is provided for carrying out preventive measures, as well as necessary repair work. They are installed on long straight runs and at joints where the pipeline changes direction or slope. Depending on this, linear and rotary structures are distinguished.
Variable
The main function of such wells is to level out differences in the height of treatment facilities if this indicator exceeds the permissible level.
Installing a differential tank allows you to combine pipelines into one network and connect sewer pipes above the level of the trays. With their help you can solve several problems at once:
- Prevent the high velocity of wastewater developing due to an increase in the angle of inclination of the terrain.
- Connect sewer outlets and deep underground collectors.
- Circle sewer pipeline around intersections of underground structures.
Depending on the internal structure, differential wells can have a multi-stage staggered design, and can also be equipped with fast flows to accelerate retarding flows or a baffle-weir wall.
Cumulative
Reservoirs accumulative type are a modern modification of cesspools.
Storage wells accumulate wastewater
Sealed containers require periodic cleaning of the contents, which can be done by using special equipment.
Designed to purify wastewater from debris and heavy suspended matter. Filtration tanks are installed in cases where the site is located on sandy as well as sandy loam soil types.
The main condition for installation filtration well– groundwater below the base at least 1 meter
Manufacturers of treatment facilities for household use offer a wide selection of filtration tanks designed for different volumes.
SNiP requirements for sewer wells
Sewage facilities have been used by people for hundreds of years. It is quite logical that the technology for their arrangement during this period was worked out to the smallest detail. Clear requirements and instructions for the construction of treatment facilities are given in SNiP2.04.03-85 “Sewerage. External networks and structures."
The document states that when installing a septic tank in a private household between leaving the house internal sewerage and a viewing well must be installed in the receiving chamber of the treatment device.
For post-treatment and disposal of wastewater after a septic tank, it is recommended to also equip a filtration tank
According to SNiP, inspection wells must be installed at connection points in the case of connecting a local sewerage system to the central collector, as well as:
- on long straight sections of pipelines;
- when turning the pipeline and at the entry points of branches;
- when the slope of the location or diameter of the pipes changes.
Attention! If the pipe diameter external sewerage reaches 150 mm, the distance between the tanks should be 35 meters, if the cross-sectional size of the pipes is 200 mm, the distance is increased to 50 meters.
As for filtration and storage wells, other location standards apply. They are based on maintaining the distance of the well from significant objects in nearby areas:
- 1 meter to outbuildings;
- 5 meters to the foundation of a residential building;
- 3 meters to the fence and the highway;
- 20 meters to landing garden crops;
- 30 meters to a pond or well with drinking water.
The current standards are designed to prevent the release of untreated wastewater into the soil, which can occur as a result of the failure of a treatment plant.
Sizes of structures
SNiP also imposes a number of requirements on the design of a treatment device for autonomous sewerage. The inspection tank must include four main elements:
- Mine.
- Working chamber.
- Neck.
- Protective cover.
Dimensions of reinforced concrete rings used in the construction of sewer wells
The shape of the protective cap is determined by the geometric dimensions of the neck. When arranging treatment facilities, round hatches are traditionally installed. The dimensions and overall characteristics of external hatches are regulated by GOST 3634 99. The key criterion when choosing the shape and size of a product is its scope of application.
Table standard sizes round hatches
When constructing autonomous sewer wells, plastic or cast iron hatches with a diameter of 450-550 mm are used.
The parameters of concrete filtration structures vary within the following limits:
- Inner diameter 1000/1250/1500/2000 mm;
- The height of the elements is from 2410 mm to 2870 mm.
The dimensions of round filter tanks are 1.5-2 meters with a burial depth of 2.5 meters. Container sizes rectangular shape on average they are 2x2.8 meters.
The cross-section of the shaft must be such that a person can freely descend into the well and, if necessary, carry out cleaning of the system and maintenance of sewer pipes. The height of the working part of the manhole is determined based on the height of the person and is on average 1.8 meters.
The depth of the storage tank pit should also not exceed 2.5 meters
The diameter of the pit for the treatment facility should be half a meter larger than the size of the well. Between the bottom sewer pipe and the level of the bottom of the pit maintain a distance of 60-70 cm. When high level underground water, when constructing a sewer well, waterproofing must be installed.
Diameters of treatment facilities
Current standards The sizes of tanks are also regulated. This parameter directly depends on the diameter of the laid pipeline.
The diameter of sewer wells according to SNiP should be:
- on pipelines with a cross-sectional area of up to 150 mm - from 70 mm and above;
- on pipes with a diameter of up to 600 mm – 1000 mm;
- with a pipe size of 700 mm - 1250 mm;
- when connecting pipes measuring 800-1000 mm - designs D 1500 mm;.
- on pipelines of 1200 mm and above - 2000 mm.
When constructing square-shaped wells, the length of each side of the tank must be at least 1 meter.
Material of manufacture
A number of requirements are imposed by the current regulatory document on the material for the manufacture of sewer wells.
Treatment facilities must have high strength and tightness parameters
When constructing sewer wells, it is permissible to use:
- Plastic structures production sample. Manufactured in full compliance with GOST standards. The consumer’s task is to choose a product of optimal size.
- Concrete rings. Reinforced concrete products are also produced by factories in accordance with current GOST standards and are offered for sale in wide range.
- Rubble or brick. Moisture-resistant materials are used in the construction of sewer wells on our own. But due to the complexity of installation, moisture-resistant brick and rubble stone are used much less frequently.
The main advantage plastic structures is that they are produced already equipped with outlets, the dimensions of which clearly correspond to the standards of pipes made of any type of material: plastic, asbestos, cement. Production sample shafts can be connected to any sewage system within 15-20 minutes immediately after installation.
How to calculate the volume and depth of a well
The depth of the sewer well in accordance with the current SNiP should be determined based on the experience of arranging operational networks in a particular area.
The depth of the reservoir depends on the structure and type of soil
Minimum value:
- 30 cm when installing pipes with a diameter within 500 mm;
- 50 cm for larger diameter pipes.
In accordance with paragraph 4.8 of the current SNiP, when constructing a sewer well made of brick, the depth of the structure must be at least 70 cm to the top of the pipe.
Tip: to prevent water from freezing in cold weather, when laying the pipeline, it is necessary to provide a slope of 0.03 meters for each meter of length. It will facilitate the flow of wastewater into the storage tank by gravity, without the use of additional pumps.
When calculating the volume of a sewer well, use the formula: V=L x 3.14 x R2, where V is the total volume for the month, L is the height of the tank, R is the radius of the tank squared. To determine the radius of the structure being built, which, accordingly, will be ½ of its diameter, the volume value V is divided by 3.14 and the height value. As mentioned above, the height of the tank on average does not exceed 2.5 meters.
For example, to build a tank with a capacity of 8 cubic meters with a structure height of 2.5 meters, you will need a tank with a diameter of 2 meters. When calculating, 20% is always added to the resulting value as a reserve.
By following the standards when calculating the dimensions and constructing a sewer well, you will protect yourself from problems associated with the operation of a wastewater treatment plant, minimizing the risk of failure of the well and contamination of the environment. It’s even simpler and more reliable to entrust all stages of design and installation of the drainage system to specialists.
Since sewer systems have been created and used for thousands of years, the technology of their equipment has been worked out to the smallest detail. This article describes correct device sewer well, as required by building regulations.
The locations and types of wells, their sizes and the requirements for these structures are regulated here.
In the case of private households with local treatment facilities(septic tank) in the area between the outlet of the internal sewage system from the building and the receiving chamber of the device must be equipped with an inspection well. Also, one of the options for recycling wastewater after a septic tank is.
An inspection well is also provided before the entrance of the local sewer system into the intra-block network or central sewer, outside the red building line (the conventional boundary separating the area for placing buildings from streets, driveways, etc.).
Important information! According to SNiP, sewer wells (inspection wells) with external sewerage pipes up to 150 mm in size should be installed every 35 m, and with 200 - every 50 m on straight sections of pipelines, as well as:
- When turning the system
- When changing pipe diameter or slope
- At the entry points of branches
The requirements for sewer wells and their components are set out: for reinforced concrete products - in GOST 2080-90, for polymer wells - in GOST-R No. 0260760.
For plastic devices, many manufacturers also develop their own specifications ( technical specifications).
Stone wells for sewerage can be made from prefabricated and monolithic concrete and reinforced concrete, brick, and filter wells can also be made from rubble stone.
When constructing sewer wells from polymers, polyvinyl chloride (PVC), polypropylene (PP), or polyethylene (PE) is used.
In addition, some models are made by combining some of the listed materials.
Dimensions that wells should have sewer SNiP means as follows:
- On pipelines with a diameter of up to 150 mm - at least 70 mm
- Up to 600 mm – 1000 mm
- 700 mm – 1250 mm
- 800-1000 mm – 1500 mm
- 1200 and more -2000 mm
- At least 1500 mm for any diameter and depth of 3 m and above
At the same time, the volume of the sewer well is not separately regulated, but, based on the given depth and diameter, it is not difficult to calculate it.
Any construction of sewer wells begins with excavation work - excavation pits and trenches. Before this, a set of preparatory work is carried out.
It includes:
- Layout (marking) of the area where the well will be located
- Removal of trees, bushes and other vegetation at the work site
- Demolition/relocation of buildings that interfere with construction
- Construction of a temporary road/ramp to the construction site
When constructing a pit for sewer wells standard project provides next order works:
- An excerpt is being held
- The bottom is cleaned
- The ground level and slope angles of the walls are checked against the design
- For stone structures: a device at the bottom of the waterproofing (usually using bitumen mastic) layer 20 cm, densely compacted
Stone wells
After this, the following work is performed for a concrete or reinforced concrete well:
- Preparing the base. Laying a slab or installing a concrete pad 100 mm thick from M-50 concrete
- Tray device the desired shape made of M-100 concrete with steel mesh reinforcement
- Sealing pipe ends with concrete and bitumen
- Insulation of the inner surface of concrete rings with bitumen
- Rings of sewer wells are installed (carried out after the concrete tray has gained strength, 2-3 days after installation) and a floor slab with M-50 mortar
- Grouting the joints between the prefabricated parts of the well with cement mortar
- Waterproofing joints with bitumen
- Tray finishing cement plaster, followed by ironing
- Installation of a clay castle at the entry points of pipes with a width of 300 mm and a height of 600 mm larger than the outer diameter of the pipes
- Well testing (carried out within 24 hours by filling it with water to the top edge, installing temporary plugs on the pipes). Considered successful if no visible leaks are detected.
- External backfilling of well walls followed by compaction
- Device concrete blind area 1.5 m wide around the well neck
- Insulation of all remaining joints with hot bitumen
The installation of brick sewer wells is carried out in a similar way, but here, instead of installing prefabricated elements, masonry.
Waterproofing is done in exactly the same way.
Thus, the installation of wells from stone materials for all types of sewerage: domestic, storm or drainage.
However, in the case of a stormwater well, lattice hatches can be installed on the well, which simultaneously serve as a catchment area.
For drainage, the well itself can be a drainage element through special holes in the walls, but this design requires special calculations.
At the same time, there are slight differences in the components that the series defines: sewer wells KFK and KDK - for domestic wastewater, KLV and KLK - for storm water, KDV and KDN - for drainage.
The table of sewer wells by size is as follows:
The process for drop wells looks a little more complicated due to their more complex configuration.
Here, depending on the specific design, in addition to the tray design, in some cases it is necessary:
- Riser installation
- Water jet equipment
- Installation of a water barrier wall
- Creating a practice profile
- Pit device
The installation of the shaft body, base and ceiling itself is carried out according to the same rules.
The only exception concerns a drop well with a riser - a metal slab must be laid at its base to prevent the destruction of the concrete part of the structure.
It looks like this:
- Riser
- Water pillow
- Metal plate at the base of the pillow
- Receiving funnel riser
The receiving funnel is designed to compensate for the vacuum that can be created in the riser due to fast movement Wastewater.
It is necessary to create differential sewer wells with your own hands using a practical profile only in exceptional cases - such a design is provided for pipelines with a diameter of 600 mm and a differential height of up to 3 m.
Similar pipe diameters in individual systems drainage systems are not used. But other types of wells can be used in local sewerage successfully.
In accordance with the requirements of SNiP, sewer drop-off wells are installed:
- If necessary, reduce the depth of the pipeline
- At intersections with other underground utilities
- To regulate the flow rate
- In the last flooded well before the wastewater is discharged into the reservoir
Typical cases when the installation of a differential well on suburban area advisable:
The meaning of this difference is that due to the creation of a large slope in a short section of the system, the drains begin to move much faster, without having time to cling to the inner walls of the pipe.
Installation of pipeline inlets into wells
Depending on the specific soil conditions, the entry of pipes into the well can be done in different ways.
For dry soil it is easier to do. Only two types of materials are used here: cement, indicated in the figure by number 1, and asbestos-cement mixture, indicated by number 2.
For wet ground specified materials Resin strand 3 and a layer of waterproofing 4 are also added.
Both methods are designed for non-subsidence soils.
In regions where ground movement is possible, the connection is made movable, using pipe winding with plastic waterproofing padding.
Sometimes a metal sleeve is inserted into the hole in the hatch wall, and the packing is placed inside it.
Plastic wells - a modern alternative
A reasonable and practical replacement for stone inspection chambers are polymer analogues.
Moreover, plastic wells can significantly reduce the volume of excavation work; constructing sewer wells from these materials speeds up and simplifies the process of installing drainage systems.
There are rumors about the compressive strength of plastic wells - but they are not confirmed by facts. This is especially true for the simplest wells for intra-yard networks.
As a rule, there are no loads that can damage the plastic.
Among other things, a concrete well with a diameter of a meter can replace a plastic well, starting from 30 cm in diameter, despite the fact that, despite the difference in size, maintenance of sewer wells made of polymers will be even simpler than their giant concrete counterparts.
After all, they are produced with outlets that clearly comply with the standards of pipes made of any material - plastic, cement, asbestos.
Therefore, immediately after installation, such shafts can be connected to any one within minutes. If they are used plastic pipes– then the process will be even faster.
Therefore, before building a sewer well, it is worth weighing the pros and cons; the apparent cheapness of some solutions is deceptive. For a private plot where one, two, or maximum three wells are installed, it will be much cheaper to install plastic wells than to try to save money by using concrete rings. The enormous weight and the need to order heavy equipment will negate the apparent cheapness of old solutions. And the modest diameter of the plastic well and the speed of installation are not the last arguments.
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The sewage system has a very ancient history, therefore its design and arrangement technology have been brought to a very high quality state. This article will discuss the main issues related to the use of sewer wells in the sewerage system.
The regulatory act regulating the requirements for sewer wells and the procedure for their installation is SNiP 2.04.03-85 “Sewerage. External networks and structures." The document displays all the factors relating to sewer wells, including their location, classification, dimensions and operational characteristics.
To install a sewer system on a private property, it is necessary to use inspection wells, placing them on the section of the pipeline between the building and the wastewater receiver. In addition, one of possible options disposal of wastewater after it passes through the septic tank is a filter sewer well.
Inspection wells must be installed not only in private households, but also on local sewer systems. The installation site must be located behind the so-called red building line, which is a conditional boundary dividing the target area into certain segments. SNiP states that sewer wells must be installed every 35 meters if the pipeline diameter is up to 150 mm, or every 50 meters for a pipeline with a cross-section of 200 mm.
In addition, inspection wells are installed if the system contains:
- turns and bends;
- changes in pipe diameter or slope;
- branches of the structure.
Brick, concrete or reinforced concrete are used to make stone sewer wells, and rubble stone is used to create filter wells. Polymer wells can be made of polyvinyl chloride, polypropylene or polyethylene. In addition to structures made from a single material, there are structures on the market made from compounds of various resources.
According to SNiP, the dimensions of sewer wells vary as follows:
- when using pipelines with a diameter of up to 150 mm - at least 700 mm;
- up to 600 mm – 1000 mm;
- up to 700 mm – 1250 mm;
- from 800 to 1000 mm – 1500 mm;
- from 1200 – 2000 mm;
- from 1500 mm with a system laying depth of 3 m.
The order of actions will look like this:
- first, the exact location on the site where the well will be located is determined;
- then the selected area is cleared of any plants (bushes, trees, etc.);
- if necessary, buildings that are located on construction site;
- It is very important to ensure unobstructed access to the site.
As a rule, a pit is created according to the following principle:
- first of all, a hole of the required dimensions is dug;
- then the bottom is cleaned;
- a check must be made to ensure compliance with the laying depth of the structure and the slope angles of the pit walls;
- in case of stone structures At the bottom of the pit you need to lay a 20-cm waterproofing layer, compacting it as tightly as possible.
Construction of concrete sewer wells
When the preparatory work is completed, the process of installing the well begins.In the case of a concrete or reinforced concrete structure, the arrangement of a sewer well will look like this:
- first the base is prepared, for which it is used monolithic slab or 100 mm concrete pad;
- Next, trays are installed in sewer wells, which must be reinforced with metal mesh;
- the ends of the pipes are sealed with concrete and bitumen;
- inner surface concrete rings must be insulated with bitumen;
- when the tray has hardened sufficiently, you can put the rings of the well itself into it and mount the floor slab, for which it is used cement mortar;
- all seams between structural elements must be treated with mortar;
- after grouting with concrete, it is necessary to ensure good waterproofing of the seams;
- the tray is treated with cement plaster;
- in places where pipes are connected, it is arranged clay castle, which should be 300 mm wider than the outer diameter of the pipeline and 600 mm higher;
- one of the final steps is to check the design for functionality, for which the entire system is completely filled with water. If no leaks appear after 24 hours, then the system is functioning normally;
- then the walls of the well are backfilled, and the whole thing is compacted;
- a blind area 1.5 meters wide is installed around the well;
- all visible seams are treated with bitumen.
The construction of a sewer well made of concrete rings, described above, is no different from the construction brick construction, with the only difference being that in the latter, concreting is replaced with brickwork. The rest of the work flow will look the same.
In addition to the tray, in order to install a drop-off well, one or more conditions may need to be met:
- installation of a riser;
- installation of a water fountain;
- arrangement of a water separator element;
- creation of a practical profile;
- pit arrangement.
Thus, the composition of the differential well includes:
- riser;
- water cushion;
- metal plate at the base;
- riser receiving funnel.
According to regulations, the installation of a well for sewerage is justified in the following situations:
- if the pipeline needs to be laid at a shallower depth;
- if the main highway crosses other communication networks located underground;
- if necessary, adjust the speed of movement of wastewater;
- in the last flooded well, immediately before the wastewater is discharged into the receiving water.
- if there is a large difference in height between optimal depth laying the sewerage system on the site and the level of the wastewater discharge point into the receiver (this option is often justified, since laying the pipeline at a shallower depth allows for less work to be performed);
- in the presence of utility networks located in underground space and crossing the sewer system;
- if there is a need to regulate the rate of movement of wastewater in the system. Too high a speed has a bad effect on the self-cleaning of the system from deposits on the walls, as well as too low a speed - in this case, deposits will accumulate too quickly, and the use of high-speed current is required to remove them. Its meaning is to increase the speed of fluid flow in a small section of the pipeline.
Connecting the pipeline to wells
Pipes are connected to the well depending on what kind of soil is on the site. In the case of dry soils, the connection is made using cement and asbestos-cement mixture. To install pipes to wells on wet soils, you need to add a resin strand and a waterproofing layer to these materials. These methods are only suitable for arranging the system on non-subsidence soils.If the soil in the area can shift, then the pipes must be connected movably, for which each of them is wrapped with plastic waterproofing padding. If necessary, you can use a metal sleeve to arrange the packing in its internal space.
Plastic wells for sewerage
IN Lately plastic structures are increasingly replacing stone wells from their positions. Plastic sewer wells are much more convenient: they are easier to install, they do not require a large amount of preparatory work, and their performance characteristics are at a sufficient level (more details: " "). There is an opinion that their strength qualities leave much to be desired, but in practice this statement has not been confirmed, because wells are usually not subjected to too high loads.
Another advantage of plastic wells is the possibility of reducing the size of the viewing window. For example, to replace a concrete well with a meter diameter, it will be enough to install a plastic 30-cm analogue, which is also much easier to maintain. Installing plastic sewer rings is easy and simple.
The installation of plastic structures is also simplified due to their light weight and versatility: the construction of plastic sewer wells provides for the presence of inlets and outlets for pipes, which cannot be said about concrete structures, in which you have to make the connectors yourself. All of these advantages indicate that for private households it would be much more reasonable to use plastic wells.
Conclusion
There are different designs of sewer wells, and the choice of a suitable device depends on the wishes of the owner of the site. This article answers the question of how a sewer well is designed and helps you choose the best option.