What is the best way to make a septic tank for your home. The most detailed and understandable instruction is the installation of a septic tank in the country. The correct location of the septic tank in a private house

Making a do-it-yourself septic tank for a private house is often chosen as a more economical alternative to buying a factory treatment plant. Self-construction requires time and effort, but it really allows you to significantly save money.

Advantages of septic tanks

If not so long ago the subject of discussion was the advantages of septic tanks over cesspool, now this aspect is beyond doubt. Much more often you can find materials about how a do-it-yourself septic tank for a private house differs from a finished one, or one of the models from another.

Indeed, the presence of a septic tank on the site provides a number of advantages:

Economy- the frequency with which you have to pay for the services of a sewage truck is significantly reduced, in the case of using the most effective multi-stage models, up to once every 10-15 years.
Compliance with sanitary standards and environmental friendliness- correctly chosen model and installation location, as well as competent installation, practically exclude the ingress of harmful substances into drinking water, into plants through the soil, into water for irrigation, etc.
Comfort- if the septic tank is working properly, bad smell absent even near the treatment plant.

Types of structures and their features

When choosing a septic tank design, they usually try to find an option that would give the best results, but would require less construction and operation costs. Under equal other conditions ( right choice volume, absence of leaks, compliance with other installation requirements, etc.) a septic tank with a large number of chambers is considered more efficient. However, the choice must be made on the basis of expediency. In addition, there are ways to improve the efficiency of the treatment plant.

Single chamber models

It is better not to do a single-chamber septic tank with your own hands for a private house with permanent residence. Such models are more suitable for giving, where the family comes from time to time. In fact, the most simple models of this type are an improved version of a conventional cesspool except that the pit does not have watertight walls and bottom, so it cannot protect against harmful substances entering the ground. In most cases, such products are cumulative and require periodic, fairly frequent removal of the contents using a sewage machine.

Pumping out a single-chamber sealed sewer tank

A single-chamber septic tank without pumping out is some exaggeration. Adding a special preparation to the tank can significantly improve the quality of water treatment and reduce the frequency of cleaning. Certain types of bacteria in the process of life decompose polluted effluents into clean water and neutral sludge that does not contain toxic substances. But even the most advanced septic tanks “without pumping out” need to be cleaned, but the need arises very rarely.

Two-chamber products

Two-chamber septic tanks in terms of design can be of two types. The difference lies, first of all, in the arrangement of the bottom of the second tank. The water settled at the first and second stages is clean enough, so in most cases it can be drained into the soil.

Water drainage can be carried out in different ways:

through the bottom of the second tank(for better sedimentation of the remaining insoluble suspension, it is covered with filter material - gravel, expanded clay, etc.),
through perforated drainage pipes, which increase the drainage area and provide a fairly rapid removal of water even in dense soils with low water permeability,
with a pump into a watering container or drainage pit.

The photo shows a standard scheme of a two-chamber septic tank for a private house or cottage

In the second and third cases, the bottom of the second tank is usually waterproof (concrete base with waterproofing).

Three-chamber modifications

The device of a septic tank in a private house with your own hands using a three-stage cleaning system will allow you to process effluents, including chemical impurities from detergents, and organic. Gradual sedimentation in the chambers allows you to get rid of not only large insoluble particles, but also suspension, and passing through a layer of filter material is final stage that removes the smallest inclusions. After conducting a quality-confirming analysis, such water can not only be drained into the ground, but also used for irrigation.

A septic tank of three tanks, the last of which has a drainage layer at the bottom for filtering treated effluents into the ground

Deep Cleaning Stations

The decomposition of impurities in such installations is also carried out with the help of bacteria. If cultures that do not require air (anaerobic) are used in non-volatile septic tanks, then the aerobic microflora of deep cleaning stations needs it. For a constant supply of air, compressors are used, so the models are called volatile.

The decomposition of air by aerobic bacteria is accompanied by a more active (than in the case of anaerobic microflora) release of biogases, therefore, effective ventilation is required for this type of septic tanks. It is possible, by analogy with simpler structures, to use a pipe rising from the tank to a certain height, however the best option will be the supply of the pipeline to the common ventilation system. In this case, the pressure in the communications should be compared so that the exhaust gases do not enter the room.

Photo of a deep biological treatment plant

The advantages of deep cleaning stations are:

maximum effective removal impurities
shorter cycle time.

Materials for manufacturing

Treatment facilities of various types can be found on sale, however, zealous owners are often interested in how to make a septic tank in a private house on their own. The simplicity of the design allows you to cope with such work without problems, it is only important to pay due attention to the following aspects:

choice of design and volume,
determination of the place for installation,
choice of material.

The last point is worth a closer look. One of the main requirements for materials for building a septic tank for a house with your own hands is accessibility. Otherwise, the meaning of self-production is lost.

We list the most common options.

Capital structures from concrete rings, brick and monolithic models are better suited for a country house with permanent residence.

Before starting the construction of a septic tank, it is necessary to make some calculations.

The total volume of the septic tank, regardless of the chosen scheme and material, should be no less than the three-day water consumption rate for residents (at the rate of 0.2 cubic meters per day for each).
The installation site of the treatment plant must comply with sanitary standards, in particular, be more than 30 meters from the source of drinking water and no closer than 5 meters from the house. And the distance between the septic tank and the nearest fence is 2 meters or more.

The following tips on how to properly build a septic tank in a private house will help make the building more economical and durable:

In most cases, it is advisable to make a reserve in terms of the volume of tanks by about 20%. In this case, an increase in the number of drains after a while will not become a difficult problem to solve.
The removal of sediment from the chambers contributes to the cleaning efficiency. Dirty tanks are not able to provide high quality.
The construction of sewerage at the stage of construction of a country house will save on the rental of special equipment. In any case, excavators and lifts are rented for a large construction site, at the same time, machines can be used for digging trenches for pipes, pits for tanks, moving concrete rings, etc.
Low quality building materials can negate all the work, so you need to save when acquiring them only within reasonable limits.

Do-it-yourself septic tanks for a private house video

And on the video you can see how the installation and installation of a septic tank in a private house with your own hands. An example is shown using concrete rings.

Making your home comfortable is the task of every owner. One of the conditions for comfortable living is an efficient system local sewerage. If earlier cesspools were mainly built to collect wastewater, today such a solution is not acceptable. Therefore, most homeowners decide to build a septic tank - an installation in which drains not only accumulate, but are also cleaned. Consider, how to make a septic tank in a private house, without resorting to the help of professionals.

Why is it recommended to build an overflow septic tank for arranging local sewage? The fact is that this installation, unlike a simple cesspool, is capable of not only accumulating, but also treating wastewater, providing water drainage. Therefore, the owners of such installations use the services of vacuum trucks much less frequently, as a rule, it is recommended to clean the chambers from sediment once a year.

It is quite possible to build a septic tank yourself. Moreover, the homeowner has the opportunity to choose which septic tank to build on his site. But before you start building, you need to learn how to properly make a septic tank so that the built installation works efficiently and is environmentally friendly.

The principle of operation of a septic tank without pumping

The principle of operation of a septic tank is quite simple. When processing wastewater, two methods of treatment are used - mechanical (sedimentation) and biological (anaerobic fermentation and aerobic purification in filtration fields).

The water purified from impurities is filtered into the soil. If the septic tank is built in clay soil that does not absorb water well, then it is necessary to carry out the drainage of water differently, constructing an annular drainage around the treatment plant.

Primary requirements

Before you make a septic tank with your own hands, it is important to remember the basic principles of its effective operation:

Multistage. The effectiveness of the settling process is ensured by the fact that the effluents go through several stages of treatment. To do this, the installation is divided into 2-3 chambers. In each chamber, the settling process takes place, and in the first compartment, large inclusions are precipitated, and in subsequent chambers, the smallest impurities precipitate. It is this organization of upholding that allows you to achieve the best results;

Tightness. This condition for the construction of a septic tank ensures the environmental safety of the installation. The tightness of the sedimentation tanks eliminates the possibility of dirty water seeping into the ground, therefore, there is no threat of contamination of the soil and soil water. In addition, the tightness of the chambers excludes the possibility of penetration of soil water into the interior, which could lead to flooding;

Advice! When building a septic tank, you need to take care not only of the tightness of the chambers themselves, but also of the junctions of the body with pipes. Silicone-based sealants or elastic seals made of rubber are widely used to seal joints.

Volume. The quality of wastewater treatment directly depends on how long the contaminated liquids are in the chambers. In order for the drains to settle well, they must be in the septic tank for at least three days. Therefore, the volume of the chambers of the treatment plant must be large enough to accommodate the effluent generated within three days;
Thermal insulation. Biological cleaning processes require sufficient heat in the installation. Therefore, if the septic tank is installed at an insufficient depth, then it is necessary to carry out work to insulate the body of the treatment plant;
Ventilation. In the process of fermentation, organic matter decomposes into simple components, including methane and other gases. To remove gaseous decomposition products, it is necessary to provide a septic tank with a ventilation pipe.

Selection of a construction site and assessment of local conditions

It is extremely important to choose the right location for the septic tank. In addition, conditions such as soil structure and groundwater levels will need to be taken into account. When choosing an installation site, you will need to fulfill the requirements of SanPiN and SNiP. Among these requirements:

The septic tank should be located at the maximum distance from the water intake. The minimum allowable distance is 30 meters;
The septic tank must be at least 5 meters away from the house;
It is not allowed to build a treatment plant close to the fence with a neighboring plot, it is necessary to step back from it by at least a meter;
It is advisable to choose a construction site so that equipment can drive up to the site. Equipment will be required during the construction process (for preparing the pit, installing heavy parts, etc.). In addition, the passage of equipment is necessary to perform periodic pumping of sediment from the chambers.

Advice! This requirement is justified by the fact that if the treatment plant is located close to each other, it is possible to wash away and prematurely destroy the foundation.

The construction of a septic tank involves not only the construction of sedimentation tanks, but also the construction of filtration fields, which are necessary to perform post-treatment of wastewater and filter purified water into the ground. When arranging such fields, it is very important to correctly assess the structure of the soil, as well as the level at which ground water.

With a high GWL or during construction on clay, it is necessary to organize water drainage in alternative ways, since the construction of a septic tank according to standard scheme under such conditions is not possible.

Advice! Under alternative scrapings in the construction of a septic tank in difficult conditions it implies the installation of ground filtration cassettes, the use of biofilters, the construction of filtration fields by partial replacement of clay soil on the site, etc.

In some cases, it is necessary to organize a forced drainage of water. This option has to be resorted to if gravity drainage is not possible. Forced drainage of water is carried out using a drainage pump, drainage is possible into a gutter or a filter well.

Pit preparation

Let's figure out how to make a septic tank with your own hands. Whichever option is chosen for the construction of a septic tank, work always begins with the preparation of a foundation pit. This work can be done in several ways:

Dig a pit by hand. This is the cheapest solution, but you will have to spend a lot of time and effort on land work;
Dig a pit by hiring a team of excavators. In this case, digging a pit will be expensive, and in time the gain will be small;
Dig a pit by renting an excavator with a driver. When choosing this option, the pit will be ready quickly, the cost of renting equipment is comparable to the cost of a team of excavators. However, it is not always possible to use the technique, for example, due to the lack of access;

The size of the pit must be larger than the body, so that there is free access to the walls of the installation during operation;
The bottom of the pit is carefully leveled. Then it is necessary to fill in sand and soil at the bottom. The height of this cushioning layer is 20-30 cm;
To install some types of septic tanks, it is necessary to sand cushion lay a concrete slab.

Advice! If you need to make a septic tank yourself in a site with high-rising soil waters, then at the stage of constructing the pit, it is necessary to build an annular drainage to ensure that rising water is removed from the installation body.

Construction options

There are several options for building an overflow treatment plant. Consider what you can build a treatment plant from and how to properly make a septic tank.

Monolithic

This is the strongest and most durable option. Construction begins with the filling of the bottom. For reinforcing concrete, metal rods or a finished metal wire mesh are used.

After the bottom has dried, they begin to build formwork for pouring walls and internal partitions. The thickness of the body of a monolithic septic tank must be at least 20 cm. At the same time, you need to remember the need to install embedded parts at the places where pipes are laid:

The inlet pipe should be located 5-10 cm above the level to which the septic tank will be filled;
The overflow pipe connecting the first and second chambers is located a little lower - at the filling level of the first chamber;
Overflows are made with a slight slope and are made of pipes with a diameter of 150 mm;
From above, the septic tank must be closed with a floor slab, in which holes for installation are set aside ventilation pipe and hatches for pumping sediment from the chambers.

From well rings

What can be used to build an overflow septic tank as quickly as possible? It is convenient to assemble cameras from ready-made concrete products - well rings. For the construction of such a septic tank, the use of lifting equipment is mandatory:

Chambers are built by placing rings one on top of the other;
To give the septic tank strength, the rings are fastened together with brackets;

It is important to seal the joints of the rings well. To do this, the joints are smeared with cement mortar, and then treated with waterproofing mastics;
The top of the wells is closed with a plate with a hole for installing a hatch.

From eurocubes

It is convenient to build a treatment plant from plastic containers- eurocubes. These containers can be purchased relatively inexpensively. For construction, a tie-in is made in plastic case pipes. For greater strength, it is recommended to weld the metal lattice frame of eurocubes by welding.

To protect a lightweight plastic septic tank from floating, the containers are fastened with bandage straps to the embedded parts of a reinforced concrete slab laid on the bottom of the pit. When building any of the listed options for a septic tank, the drainage of water from the treatment plant is organized so that the liquid enters the post-treatment plant.

But the installation option for post-treatment is selected depending on the geological conditions at the site. This can be a filter well, platforms with a drainage layer or an additional biofilter. Discharge of water from a septic tank without post-treatment is strictly prohibited.

So, before making a treatment plant, it is necessary to correctly determine the volume of its chambers, remember the basic requirements for placing a septic tank on the site, correctly assess the characteristics of the soil and select a construction site.

Sewerage is one of the most important engineering systems of a country house. The level of comfort of those living in the cottage largely depends on its correct and uninterrupted operation. Often, novice developers, in an effort to save money, are in a hurry to make a septic tank without proper knowledge about the absorbing capacity of the soil on the site, the level of groundwater and sanitary standards applicable to this type structures. As a result, the septic tank turns into an ordinary cesspool filled with water.

The matter is aggravated by the fact that no one has the desire to dig pipes or climb into already commissioned wells filled with “black and gray waters” in order to eliminate the breakdown or carry out modernization. There is only one way out - to do everything at once, as it should, the first time, and the experience of the user of the portal with the nickname will help you with this Pavel TLT.

How to do homemade septic tank from reinforced concrete rings.
How to conduct a hydraulic test of a sewer pipeline.
How much does it cost to make a septic tank from reinforced concrete rings.

DIY septic tank

Pavel TLT FORUMHOUSE User

I started building a septic tank from concrete rings in 2013, even before the construction of the house began. I planned everything in advance, and also took into account the exit point of the sewer pipe from the foundation. First of all, I dug a pit for rings with a size of 2000x4000 mm and a depth of 3000 mm. The pit was dug by a backhoe loader.

In a mechanized way, they dug a pit in 1 hour, taking out 24 cubic meters. m of soil. The cost of digging (note: hereinafter the prices are for 2013-16) - 1500 rubles for 1 hour. The minimum order amount is 4 hours. 1 hour the user paid for the road, because The site is located 15 km from the city.

Important: practice shows that most often it is more profitable to involve equipment for earthworks than to try to dig a foundation pit by hired workers. In order not to drive a tractor or a bulldozer several times to dig a septic tank, and then a trench, it is better to guess so that it can be done at a time maximum amount work. For example, a user ordered an excavator to dig a foundation, level the site, and at the same time dig a hole for a septic tank.

The next step is digging a trench from the house to the septic tank for laying the 110-ki sewer pipe 10 meters long.

Trench depth from 1400 to 1600 mm, because a slope of 2 cm per 1 linear meter of pipe was observed. Also, a reserve was made for a leveling sand "cushion" 100 mm thick with the expectation that the track would enter the pit at a depth of 1500 mm.

Pavel TLT

The width of the trench is approximately 35 - 45 cm. It was dug by 1 laborer. In total, he took out 6 cubes of soil, which took him one day. I paid 1000 rubles for this work. and fed the worker a good meal.

The user then bought "red" sewer pipes intended for laying the outer part of the route running in the ground. It:

Sewer pipes with a diameter of 110 mm and a length of 3000 mm. 5 pieces. at a price of 631 rubles. for 1 piece Total: 3155 rubles.
Rotate 45 degrees. 2 pcs. for 69 rubles. Total: 138 rubles.
Plugs - 2 pcs. 41 rubles each Total: 82 rubles.
Steel pipe with a diameter of about 16 cm - a "sleeve" for the withdrawal of a sewer pipe through the foundation. 1 PC. 2500 mm long. Total: 900 rubles.

After laying and mounting the pipes at the bottom of the trench, the user decided to perform a hydraulic test of the system before the track was backfilled. To do this, he drowned out the outlet of the sewer pipe in the pit, and poured 5 liters of water into the vertical outlet in the "house".

As a result, the plug could not withstand the pressure of the water column in the vertical section and flew out. On the second try Pavel TLT turned the end of the pipe in the pit so that the plug rested against the wall of the pit.

He again poured water into the pipeline and began to monitor the level (mirror) of water in the vertical outlet.

Pavel TLT

A small leak appeared due to the skew of the last section of the pipeline. For 1 hour, the water in the vertical outlet dropped from the top down by about a few centimeters. I'll work on the area where the leak is. In my opinion, it is better to check everything in advance than to bury the pipes at random, and then think about where the drains go.

Installation of rings under a reinforced concrete septic tank

The user's septic tank is a classic and well-established scheme of concrete rings, combined into two wells connected by overflows.

The first well has a sealed bottom, the second - a filtering one, without a bottom, will be perforated and sprinkled with rubble.

This scheme of the septic tank "works" only with a low level of groundwater and good absorption capacity of the soil. With a high GWL, the second well will soon be flooded with groundwater, with all the ensuing negative consequences.

This article talks about when the groundwater level is high. According to the user, at first he wanted to buy "GOST" concrete rings. Searching, I found the following suggestions:

concrete ring with a diameter of 1500 mm - 3840 rubles;
concrete ring with a diameter of 700 mm - 1580 rubles;
transition cover from a ring with a diameter of 150 cm to a ring with a diameter of 70 cm - 3800 rubles;
bottom for a concrete ring - 5300 rubles.

The last amount (the bottom for the first hermetic well) did not fit into the planned budget at all. After asking the manufacturer why the bottom is so expensive, the user found out that the bottom for a ring with a diameter of 1500 mm goes with a diameter of 2000 mm. Hence the high price.

Pavel TLT

At first I wanted to fill the bottom of the first well with self-mixed concrete, but decided to look for more. As a result, I found "Negostovskie" rings and a bottom suitable for me, which are made by local small-scale production, at a reasonable price and of good quality. In the end I bought:

bottom with a diameter of 1800 mm - 1 pc. - 2400 rubles;
ring with a diameter of 1500 mm, a height of 900 mm - 2 pcs. - 3100 rubles;
ring with a diameter of 1500 mm, a height of 600 mm - 2 pcs. - 2500 rubles;
cover "15" with a hole for a ring with a diameter of 700 mm - 2 pcs. - 2400 rubles;
ring with a diameter of 700 mm, a height of 600 mm - 4 pcs. - 1250 rubles;
polymer-sand manhole - 2 pcs. - 1250 rubles.

Delivery of the rings by a truck with a manipulator and their installation cost 3 thousand rubles.

During the installation of the rings of the first well, the joints were smeared with cement-sand mortar, and fragments of flat stones were inserted between the rings of the second (filtration) well (for drainage).

The picture below shows that the depth of the pit and the trench coincided, and the top of the ring protrudes by the planned amount.

The user left the installation of hatches “for later”.

To check wells PavelTLT, from fittings "12-ki", welded a ladder 3 m long, along which you can go down to revise the system.

The next stage is the completion of the filtration well and the final hydraulic check of the assembled sewer system.

Installation of overflows in the septic tank and hydraulic testing of the sewer pipeline

To create a filtration "cushion", the second well was carefully sprinkled with crushed granite fraction 5-20.

In total, the user ordered, taking into account the further construction of the foundation of the boiler room and the pouring of the underfloor heating screed, about 10 tons of crushed stone. Crushed stone + delivery cost a little less than 14 thousand rubles.

Also, the user decided to increase the filtering capacity of the second well by drilling holes in the walls of the ring. But first you need to check the tightness of the system, because. A lot of time has passed since the laying of the pipes in the trench.

Hydraulic testing consists of several steps:

We muffle the outlet of the sewer pipe with a plug so that it does not fly out under the pressure of water.

Fill the top drain with water.

We monitor the level of the "mirror" of water.

Pavel TLT

Almost immediately I saw that the water was leaving. This means the system is not sealed. I went to look for a leak. Well, the trench has not yet fallen asleep.

After inspecting the pipes, it turned out that water was oozing from the junction that was extreme to the septic tank.

According to the user, most likely the seal turned up during installation. The solution to the problem is to put 1 pipe of greater length in order to reduce the number of joints and carry out installation work more carefully.

Same Pavel TLT engaged in perforating the walls of the well. It turned out that the case is complex, long and dreary. The holes were drilled with a crown with a diameter of 45 mm and a powerful perforator. When a crown tooth hit the armature, it broke, or the perforator was knocked out of hand. After making a few holes on his own, the user decided to hire assistants for this work, and this is what happened in the end:

The first worker drilled 70 holes in 8 hours.
The second worker was able to drill only 45 holes in 7 hours. Having failed to hold the jammed puncher in his hands a couple of times and having received a tool on the head, the helper refused to work.

Remuneration of workers for 2 days - 2.4 thousand rubles.
Broken 3 drill bits - 1170 rubles.

Total: 3570 rubles were spent on drilling 115 holes.

After calculations, the user found that the perforation of the ring was 8% of the total wall area (taking into account the gap between the two rings), with a required minimum coefficient of 10%. After calculating the required area of the remaining perforation area (0.24 sq. m.), Pavel TLT I took up the tool myself.

First of all, the user drilled holes with a diameter of 12 cm for the outlet of the sewer “110th” pipe and overflows.

The hole was first drilled with a bit, and then expanded with a chisel blade.

Then he expanded the already drilled holes, turning them into vertical slots and, thereby, increasing the perforation area.

Pavel TLT

I made a total of 14 slots 300 x 45 mm, with a total area of 0.34 square meters. m. So total area perforation more than 10%.

Expanding holes made by drilling is easier than making new ones.

At this stage, the construction of the septic tank entered the final phase.

So, a “red” sewer pipe was introduced into the septic tank.

To simplify installation, the pipe joints were smeared with liquid soap.

The overflow is also made of a "red" pipe.

Tees - from gray.

The lower part of the tees is extended with pipe cuts 35 cm long.

At the finish line, the user performed a stress hydraulic test.

To do this, in order not to use the compressor and first, properly plugging the outlet to the septic tank, Pavel TLT mounted a vertical pipe in the house.

In private households, in the absence of a centralized sewage system, it is better to equip not an ordinary cesspool, but to make a septic tank for a house with your own hands. soil post-treatment. However, when building it, you should be extremely careful. Any violation of sanitary norms and rules can turn into a serious problem.

Principle of operation

Kinds

According to the filtration methods, all sewer tanks for private houses can be divided into:

1 Cumulative: conventional cesspools that require regular cleaning

2 With soil post-treatment: provide several overflow tanks interconnected by pipes; the waste entering them, under the influence of gravity, settles with sediment falling to the bottom, which is eventually processed by bacteria; the gas formed during the decomposition process is removed through special ventilation holes; settled water is poured through a pipe into filtration wells or fields

3 Deep cleaning stations: such installations are quite expensive and energy-dependent; economically viable only in cases where the height of groundwater is less than 0.4 m; cleaning in these cases is carried out using biofilters; in principle, such stations can also be used for complete 100% sewage treatment

To avoid deformation, septic tanks should be made of high-strength concrete or concrete rings. It is also possible to build containers for collecting and cleaning waste from bricks, provided that they are reliably waterproofed.

When using plastic tanks, they are installed in reinforced concrete boxes. You can also buy special containers equipped with stiffeners.

If an ordinary cesspool is a waste collector that has to be periodically removed, then it will be less common to pump out septic tanks with soil aftertreatment. Ideally, this can happen once every 10-20 years.

In practice, when building a septic tank of sufficient volume, it is cleaned every 3-5 years. Deep cleaning stations do not require this - all waste in them completely decomposes.

Before lowering the plastic septic tank into the pit, the container is filled with a small amount of water to equalize the pressure. Otherwise, when backfilling, the container may be deformed.

Calculation of the volume of a septic tank

According to SNiP, if there is a water supply, sewerage, bath or shower in the house, about 200 liters of water are required per person per day. Accordingly, for a family of 4 people per day, it will merge 800 liters or 0.8 cubic meters. m.

With a daily shower, installed dishwasher and washing machine, a maximum of 150 liters of water is consumed. For four people, respectively, this figure will be 0.6 cubic meters. m.

The volume of receiving tanks should be 3 times the daily volume of wastewater. But it is better to use tanks with a small margin. That is, for a family of 4 people, build a septic tank with a volume of 3.0-4.0 cubic meters. m.

Selecting a location for installation

Do-it-yourself construction of a septic tank for a house and a summer residence near housing and reservoirs is strictly prohibited. According to SNiP, you have the right to install it 1 m from outbuildings and 5-7 m from residential buildings.

Do not forget that, although less often than a regular pit, the septic tank will still have to be pumped out periodically. Therefore, it is necessary for him to choose a place that is most convenient for the access of a sewage truck.

Installation step by step

Let us describe in detail the process of manufacturing a septic tank for a house from concrete rings. The number of chamber sections does not matter much - only the volume of the septic tank and the correct location of the drains are important.

Pit preparation

Each tank will require a separate pit.

They can be arranged in one line or arranged in the form of a triangle:

1 Concrete tanks must be installed above the level of groundwater passage.. In this case, the drain pipes should be located deeper than the freezing point (this indicator for different regions Russia is different). In the Moscow region, this figure is 1.4 m. If they are located horizontally above the specified level, additional insulation is required.

2 Work should begin in the hot season so that groundwater drops to its lowest point.. Otherwise, the installed containers may simply float up.

3 For ease of installation, make the width of the pit slightly larger than the dimensions of the container. For a concrete ring 1 m wide, a margin of 20-30 cm is required.

4 To avoid soil pressure on the container, a layer of gravel is poured into the bottom of the pit. In the absence of such a cushion, the reservoir may be deformed or displaced.

Pipeline laying

1 For the sewer pipeline, corrugated products made of polyethylene are used, which have sufficient resistance to deformation and are able to withstand significant temperature changes. Please note that these pipes have Orange color and marking SN 8. They are more rigid and consist of several layers. Gray or white SN 4 pipes are not suitable for indoor installation - they can simply be crushed under the weight of the soil.

2 Pipes must be laid in concrete trays with sand filling the trench.

3 For free runoff of waste in the tank, the pipes are laid at an angle. With their diameter of 110 mm, it should be 2 cm per meter. With a diameter of 160 mm for each meter, the slope will be 1.5 cm. A larger angle of inclination is not required, otherwise the pipes will become clogged.

4 Pipes going into receiving tanks must have tee fittings at the end, open at the top and bottom. In this case, the liquid flow will be redirected correctly, and the debris and fatty film floating on top will not overflow. The lower outlet is intended for sampling the lower layers of the liquid, and the upper one is for cleaning.

5 For the correct functioning of the system, the overflow pipes must be located below the layer of fatty film, but not higher than the deposited layer, which collects on the bottom in the form of sludge and is subject to periodic pumping.

6 When laying, try to avoid turns. If you can’t do without them, be sure to install inspection wells for cleaning in such places.

Installation of concrete rings

1 The most common do-it-yourself septic tanks for private houses are containers made of concrete rings. You can also use monolithic concrete structures, but it will take much more time to erect them, install formwork and pour concrete, and the cost will not be much cheaper.

2 Concrete rings are lowered into the prepared pit using machinery or manually.

3 The bottom ring of the first settling tank must have a concrete bottom. If it is not possible to purchase such a design, you can concrete the bottom of the pit itself, and when installing the ring, carefully seal the junction.

4 For a filter well (more about it below), you will need to purchase rings with a perforation of 30-50 mm. With good filtration capacity of the soil, a conventional non-perforated ring without a bottom can also be used.

5 In the upper part of the septic tank, rings are installed, equipped with holes for an inspection hatch.

6 To protect the rings from displacement, they are fastened together with metal plates.

7 In order to prevent wastewater from entering the ground, when laying concrete rings, their joints are carefully sealed with bitumen or modern sealants, for example, a bastion.

8 To ensure oxygen deficiency (anaerobic bacteria can only work under such conditions), hydraulic seals and blockers are installed at the inlet and outlet of the second chamber. For the operation of such bacteria, the presence of a temperature of 10-35С is also required, therefore, septic tanks installed above the level of soil freezing additionally insulate them

9 After connecting the pipeline, the container is filled with expanded clay or sand. This will allow you to better regulate the temperature inside the treatment system.

10 Adequate ventilation must be provided to remove the explosive methane gas generated during the processing of waste by bacteria. For this, risers are used, which are located 70 cm from the soil surface. So that smells do not spread throughout the site, it is better to raise them above the roof of the building to a height of up to 0.3 m. You should not make a pipe that is too high, otherwise it will freeze over.

Scheme for the manufacture of a septic tank for a private house with the obligatory arrangement of ventilation

On clay plots, the installation of septic tanks and their soil post-treatment is impossible. Most often, in such places, groundwater also rises high. In these cases, it is necessary to use completely sealed plastic or steel products or install expensive aeration deep cleaning plants.

Calculation of the volume of the filtration well

Such facilities are allowed to be used with a volume of wastewater up to 1 cubic meter. m per day. The depth of the filtration well is calculated so that its bottom is 1 m above groundwater.

The size of such a container is calculated based on the average daily amount of effluents. For sandy soil per 1 sq. m should account for 80 l / day. For slurries, this number is reduced to 40 l/day.

The bottom of the filtration wells at 1.2 m is covered with crushed stone or gravel. At the same time, stones of the largest fractions are laid below, and small stones are laid on top in a small layer. In this case, when silting, this layer can be easily removed, and the lower part of the well can simply be washed with water.

The hole for the pipe connecting the septic tank to the filtration well must be located at least 15 cm from the backfill level. To provide access to the well cover, a hatch with a diameter of 70 cm is equipped. To protect it from freezing, it must have two covers that are laid with heat-insulating material.

In the overlap of the well is displayed exhaust pipe, which should rise above the ground by 30 cm. Its diameter is from 10 cm. After installing concrete rings, the space between them and the ground must be covered with crushed stone and gravel.

The main disadvantages of such structures include the presence of free space on the site for laying drainage pipes and a long level of cleaning - for full filtration, such a field must have a significant length.

Therefore, it makes sense to build drainage fields in cases where, with a high rise in groundwater (up to 2.5 m), the arrangement of deep-seated filtration wells becomes impossible.

The size of the drainage field and the number of trenches to be laid depends on the volume of the septic tank. Up to 30 liters of purified water should fall per 1 meter of pipes laid per day. For sandy soils that can absorb less liquid, this parameter is reduced to 15 liters. For loams, it will be even smaller - the length of the pipes will have to be increased.

The diameter of the perforated pipes is 11 cm. In order for the liquid to be evenly distributed over the site, the distance between the pipes must be 1.5 m. Their length must be maintained no more than 20 m. Each of them is equipped with a ventilation riser, which must rise above the ground by 0, 5 m

In order for the liquid to flow freely into the ground, the pipes are laid with a slope of 2 cm per linear meter. The average depth of the trench is 2 m. It must be borne in mind that its bottom should be at a distance of 1 m from the groundwater level. When laying pipes at a shallow depth, they will need additional insulation.

At the bottom of the prepared pit, a layer of soil 10 cm high with good filtering ability is first poured. On clay soils its height should be increased to 70 cm.

Septic tank from monolithic concrete

When constructing septic tanks for a house from reinforced concrete there is no need to attract special equipment - all work can be done manually. Such containers can have a different volume - you no longer have to focus on the size of concrete rings.

However, the construction of such a septic tank will be more laborious:

1 For the arrangement of a 2-3 chamber septic tank, a rectangular pit is being prepared. Since it will be a form for future construction, it is better to dig it out by hand so that the walls are as even as possible. The excavated earth can be removed or scattered in an even layer over the site.

2 On both sides of the pit, trenches are prepared with a depth below the freezing level of the soil for laying pipes. The first trench is laid towards the house, the second - towards the filtration well or drainage field.

3 To protect concrete from moisture, a sand and gravel cushion is poured into the bottom of the pit with a layer of 20-30 cm.

4 The bottom of the pit is poured first. To do this, use the standard cement mortar from high-quality cement M300-400. When using cement M400, the proportions by weight in kg (cement, sand, crushed stone) will be 1.0: 1.2: 2.7. The amount of water depends on the moisture content of the materials used.

5 To ensure that moisture from the solution does not go into the ground, a waterproofing layer of a sufficiently thick polyethylene film is laid on the bottom before pouring. It is placed overlapping.

6 To reinforce the bottom and walls of the container, use metal mesh or rods. To protect against rust and ensure structural strength, the mesh must be placed in the center of the formwork at a distance of 7 cm from the edges. It is necessary to maintain the same distance from the bottom of the pit.

7 After arranging the formwork, pipe overflows are installed in the upper part of the tank. Otherwise already cured concrete will have to be hammered.

8 To protect the solution from leakage, a plastic film is placed in the formwork.

9 To reduce the risk of voids, pouring is done in stages with a height of each layer of 0.5 m with a break of 2-3 days. The solution must be compacted with bayonet shovel or vibrator.

3 chamber system

At correct installation septic tank maintenance is reduced to a minimum:

for the smooth functioning of the system, make sure that oil products, solvents, household poisons, alkalis, alcohol and other aggressive chemicals that can kill anaerobic bacteria do not get into it; clogging of the septic tank is also facilitated by the entry into the sewer of construction debris and inorganic residues that are not decomposable
at correct operation thick sediment will have to be pumped out infrequently - once every 2-3 years; it is necessary to call vacuum trucks if it rises closer to the surface by 20 cm
it is not necessary to pump out the septic tank completely, leaving 10-20% so that anaerobic bacteria, that is, “sourdough”, remain at its bottom
Bacteria need a constant supply of organic matter to keep them alive, so garden plots, not used for permanent residence, it is better to equip not a septic tank, but an ordinary cesspool

Dachas and country houses have long ceased to be housing with conveniences "in the yard". New technologies and materials allow short term build a complete sewerage system that will ensure the removal of waste from the kitchen, toilet, bathroom or bath. Most often, it is not possible to connect the drain line to a centralized network, so the problem of removing sewage from the site has to be solved independently, using the services of a sewer or dumping wastewater into the ground. Of course, in the latter case, you can build a simple drain pit from improvised materials and thereby avoid financial costs, if not for one caveat: direct discharge of sewage into the ground can lead to groundwater pollution in your and neighboring areas.

In order for “both the wolves to be fed and the sheep to be safe”, it is worth spending a small amount and building a septic tank that will clean the drains and make them safe. And so that the costs of its manufacture and operation do not lead to the depletion of the family budget, we recommend that you do the construction yourself.

Septic tank - how it works

A carefully made septic tank will absolutely not interfere with the site, even if installed in a conspicuous place

The issue of waste disposal suburban areas can be solved in two ways. The first is the accumulation and subsequent removal of sewage with the help of sewage trucks, and the second covers a whole range of processes for filtering, absorbing and disinfecting them.

Storage type septic tank requires regular pumping

Using a sealed container to collect wastewater is a good option when people appear in a country house or cottage on weekends and the amount of water used is small. If regular operation of the bathroom, toilet and household appliances is planned, then the volume of water increases so much that the drain pit will have to be pumped out weekly. To avoid this inconvenience, cesspools of a filtration type are constructed, in which the liquid from the sewer is absorbed into the soil. There, with the help of bacteria, it is processed into water and safe organic substances. In fact, a septic tank is just such a structure, however, its improved design allows you to disinfect drains even before they are discharged into the ground.

Depending on the design of the septic tank can be divided into several types:

Single chamber septic tank. It is a container with an overflow pipe and is used in small households with water consumption of not more than 1 cubic meter. m per day. Despite the simple design, the efficiency of sewage treatment leaves much to be desired.
Small double septic tank. It consists of two containers connected by an overflow system. The simplicity and efficiency of this design makes it the most popular for DIY.
multi-chamber structures. Due to the presence of several chambers, wastewater treatment takes place over a long period of time. This allows you to get water at the outlet, which can be safely discharged into natural reservoirs or used for household needs. Despite the high degree of purification, multi-chamber systems are few in private farmsteads due to their complexity and high cost.

In order to understand how a septic tank works, consider the most popular two-chamber design.

The device and principle of operation of a two-chamber septic tank

After the sewage gets from the sewer into the first chamber of the treatment plant, they are gravitationally separated into liquid and solids. At the same time, the processing of organic waste by aerobic and anaerobic bacteria begins, which develop in the absence or excess of oxygen. At the same time, not only liquid waste, but also fecal masses are processed into water and harmless organics. By the way, the work of microorganisms allows you to repeatedly reduce the volume of the solid fraction, leaving only a small sediment in the form of sludge.

An overflow channel is located in the upper part of the first chamber, through which the purified liquid enters the second chamber, where it is further purified. Below the level of the inlet channel in the second tank there is an outlet pipe, from which the purified liquid is taken for watering the garden or draining into the ground. In the latter case, filtration fields or wells are equipped to increase the contact area of treated water with the soil.

Advantages and disadvantages of septic tanks

The question of which is better - a cesspool or a septic tank, is best considered in terms of efficiency, as well as the cost of manufacture and maintenance. At the same time, it is important to remember about the safety of the structure.

Note that in most parameters it is the septic tank that wins, which is distinguished by such advantages:

high degree of purification of domestic wastewater - the water at the outlet of the device can be used for economic purposes;
absence bad smell Location on;
hermetic design reduces the risk of sewage entering groundwater and makes the structure safe for the environment;
there is no need for regular pumping - the removal of the sludge residue can be carried out once every few years.

The disadvantages of septic tanks include:

more complex design;
increase in the cost of construction;
strict requirements for the use of household detergents. Conventional chemistry is detrimental to microorganisms, so you have to use special compounds;
a decrease in bacterial activity with a decrease in temperature - at 4 ° C and below, the sewage processing process stops.

Despite some nuances, the use of a septic tank allows you to preserve the nature and health of others, and this is a plus that cannot be crossed out by any difficulties and financial costs.

Design and preparations

The apparent simplicity of the design of the septic tank is very deceptive - in order for the constructed structure to be safe and productive, it is necessary to make small calculations and carefully approach the choice of location.

Choice of site location. Sanitary standards

Scheme indicating the requirements for the location of the septic tank on the site

When choosing a place to install a septic tank, they are guided by the norms of sanitary and epidemiological legislation and acts of SNiP:

local sewerage facilities are allowed to be installed at a distance of at least 5 m from the foundation of a residential building and 1 m from utility and utility buildings. household purpose located on the site;
distance from wells and wells is determined depending on the composition of the soil and can be from 20 m for clay soils up to 50 m for sandy soil;
installation of a septic tank directly at the roads and site boundaries is prohibited. It is required to maintain a distance of at least 1 m from the fence and 5 m from the road;

In addition, we must not forget that from time to time you still have to use a sludge pump, so you must definitely consider how the sewage truck will drive up to the sewage facilities.

A household fecal pump with a grinder will allow you to do without the services of a sewer

You can do without the services of a sewer if the sludge is pumped out with a fecal pump purchased for this purpose, and the sludge from the septic tank is used as a fertilizer for the garden.

The choice and calculation of the material. Required volume

For the installation of septic tank chambers, you can use both ready-made tanks and do-it-yourself containers:

Quantity calculation required material depends on the volume of the septic tank, so the main calculated value is the daily amount of wastewater discharged. It is not necessary to accurately determine this parameter; it is enough to take a water consumption of 150–200 liters for each family member permanently residing in the house. This will be enough to use the bathroom, toilet, washing machine and dishwasher. To determine the volume of the receiving chamber of the septic tank, the resulting value is multiplied by three. For example, if five people live permanently in a house equipped with all amenities, then you will need a tank designed for 3 cubic meters. m of liquid waste (5 people × 200 liters × 3 = 3000 liters).

The second chamber is calculated based on the size of the receiving tank. If its volume is taken equal to 2/3 of the entire size of the septic tank, then the dimensions of the post-treatment chamber provide the remaining third of the volume of the structure. If we take the example discussed above, then the working volume of the structure will be 4.5 cubic meters. m, of which 1.5 cubic meters. m is taken under the second tank.

Photo gallery: drawings of future structures

When designing a septic tank, you can use drawings and diagrams of working structures.

Scheme of a two-chamber septic tank Drawing of a two-chamber septic tank Drawing of a two-chamber septic tank

Calculations of external dimensions are carried out using well-known geometric formulas for determining the volume of a cylindrical structure and a rectangular container.

It should be understood that in most regions the septic tank will not freeze in winter due to warm drains coming from the house, soil temperature and the work of microorganisms. However, you still have to deepen the structure. The gap between the cover and the upper level of wastewater is taken equal to the amount of soil freezing in winter. It is at this depth drain pipe enters the septic tank. Therefore, it is necessary to rely on the fact that the calculated working volume will be below this point. In addition, at a higher temperature, bacteria will more actively process sewage, contributing to an increase in the performance of the septic tank.

Scheme explaining the need to deepen the chambers of the septic tank

Which form is better

The question of which septic tank is better - round or rectangular, can be considered incorrect, since the shape does not affect the performance and degree of cleaning at all. However, the configuration of the structure is of great importance in the choice of materials. Everyone knows that round buildings are the most optimal in terms of spending the necessary funds. The septic tank was no exception. If it is made of brick, then the choice of a cylindrical shape will reduce consumption by 10 - 15%. In addition, round walls perfectly resist mechanical loads from the ground. If you choose a monolithic two-chamber structure, then it is better to make it square or rectangular. Firstly, the reinforced walls will withstand bending forces, and secondly, this is necessary for purely practical reasons related to the manufacture of formwork for pouring concrete.

The cost of septic tanks various materials. To eliminate the effect of devaluation, prices are given in US dollars. e

By the way, we recommend making a concrete structure with your own hands. If we consider the cost of a septic tank, then it will not be much higher than inexpensive brick counterparts (see table). As for the durability and strength of the structure, there can be no question of any comparison, therefore, even a more labor-intensive technology will justify itself many times over. We will tell you in detail about how to build a rectangular two-chamber septic tank made of reinforced concrete.

Necessary tools and materials

To build a concrete treatment plant you will need:

crushed stone, sand and cement for the manufacture of concrete;
steel bars or reinforcement with a diameter of at least 10 mm;
metal corners, pipes or channels for the construction of floors;
boards, beams and slats for formwork;
film for waterproofing;
concrete mixer;
containers for bulk materials and concrete;
Bulgarian;
manual tamper;
saw on wood;
welding machine or wire for the manufacture of armored belts;
a hammer;
building level;
roulette.

If it is necessary to insulate a septic tank, this list should be supplemented by the heat insulator used, for example, expanded clay chips.

Do-it-yourself construction and installation of a country septic tank made of monolithic concrete

It is better to dig a pit for a septic tank by asking relatives and friends for help

After determining the size of the structure and choosing a place, they begin to dig a pit. The size of the pit is chosen depending on which formwork will be used. If it is planned to install boards from boards on both sides, then the pit is made 40 - 50 cm wider than the size of the tank, taking into account the thickness of its walls. In the case when concrete will be poured between the formwork and the ground, the pit is dug along external dimensions septic tank. If hired people are used for this, calculate the cost of their work. Be sure to keep in mind that the soil will have to be removed from the site, and this will entail additional costs for its loading. Perhaps the total cost of all earthworks approach the cost of operating an excavator. At the same time, he will cope with the work ten times faster.
It is not necessary to take out all the soil from the site. Be sure to leave some of it for backfilling the septic tank.
Tamp the bottom of the pit and fill it with a layer of sand 10–15 cm thick. After that, the sand is spilled with water to compact it.
Install formwork around the perimeter of the structure. If a one-sided board fence is used, then the walls of the pit cover polyethylene film. This will prevent them from shedding during the pouring of the walls and the base of the septic tank.
Pit wall waterproofing
Lay the pieces on the bottom wooden slats at least 5 cm thick. They will be needed as spacers for the reinforcement belt, which will be located inside the concrete base.
Build an armored belt from a metal bar or reinforcement. To do this, longitudinal elements are laid on the rails, and the transverse elements are attached to them by welding or tying with wire. The size of the cells of the resulting lattice should be no more than 20 - 25 cm.
A voluminous reinforcing frame is not required in the manufacture of a septic tank: a simple planar reinforcement is sufficient.
Fill the base of the septic tank with concrete and compact it with a bayonet or rammer. The thickness of the bottom must be at least 15 cm. To prepare a mortar from grade 400 cement, you can use the following proportion: 1 part of cement is mixed with 2 parts of sand and 3 parts of crushed stone. When using cement M-500, the amount of bulk materials is increased by 15 - 20%.
Pouring the base of the septic tank with concrete
After the concrete base has finally set, proceed to the construction of the formwork of the walls and partitions of the septic tank. Reinforcement is also installed inside the formwork to strengthen the structure of the structure.
If there are not enough boards to build the formwork to the full height, then you can use a low sliding structure, which is poured with concrete, and after it has set, it is moved up.
At the level of overflow channels and entry-exit points sewer pipes windows are made by installing large-diameter pipe sections into the formwork or by constructing plank frames.
Construction of formwork for walls and internal partitions
After the chambers of the septic tank are reached required height, proceed to the construction of the ceiling. To do this, support elements made of steel corners or profile pipes. At the same time, it is important to ensure sufficient strength, since concrete has a significant weight.
When installing formwork and reinforcement, take care of openings for hatches.
Before pouring the ceiling, be sure to install a ventilation pipe
After the ceiling has dried, a sewer line is brought into the receiving window of the first chamber, and the outlet of the structure is connected to drainage structures.
They fill the septic tank with soil, constantly tamping and leveling it. It is important that the level of the soil above the septic tank is slightly higher than the level of the entire site. This will prevent the treatment plant from flooding during heavy rains or floods.

Arrangement of filtration facilities

In order to divert purified water into the ground, use drainage systems various types. The most common structures are filtration fields and drainage wells.

Filtration field device

The first are a system of pipelines placed in the ground and connected to the outlet pipe of the septic tank. Thanks to the installation at an angle, the movement of treated effluents through the pipes is ensured, and their absorption becomes possible thanks to the system of holes and the drainage layer, in which the entire structure is placed.

The latter are a special case of a cesspool without a bottom and can be constructed from perforated concrete rings, staggered bricks, or old car tires. To ensure the absorption capacity, the bottom of the filtration well is covered with a thick layer of crushed stone. I must say that, unlike a cesspool, the performance of a structure connected to a septic tank practically does not decrease with time. This is due to the absence of solid particles and suspensions that can clog drainage holes and pores.

Using a septic tank, it is necessary to radically reconsider the approach to the use of sewage. From the day the system is put into operation, it is forbidden to use chemical detergents and pour any aggressive substances into the toilet bowl or sink. It must be remembered that from now on, living beings - bacteria and other microorganisms - are engaged in wastewater treatment. Of course, this does not mean that for washing and cleaning you will now have to use ash and simple laundry soap like our ancestors. When using household detergents marked "Bio" or "Eco", nothing will threaten the fragile ecosystem of the septic tank, and you will receive good result when cleaning and washing.

The use of detergents that are free from aggressive chemicals will allow the septic tank to work at full capacity.

Non-organic waste and garbage should not be drained into the sewer - there is a trash can for this. Getting into the storage facility of the sewage facility, they will collect at the bottom and interfere with its normal operation, and when pumping out sludge, they can clog the hoses of the fecal pump.

To improve the performance of the septic tank, special bioactivators are periodically added to the receiving chamber, which include several varieties of aerobic and anaerobic bacteria. When choosing biological products, it is imperative to pay attention to their purpose, since such compositions are produced both for normal operating conditions and for cleaning heavily polluted walls of septic tanks, drains with an increased fat content, etc. By the way, the compositions must be used exactly as indicated manufacturer on the packaging, otherwise the bacteria may die.

The use of bioactivators improves the performance of the septic tank

From time to time you will have to check the level of sedimentary deposits. The fact is that their accumulation leads to a decrease in the usable volume and a decrease in the performance of the septic tank, therefore, from time to time, sludge will need to be pumped out or removed using a sludge pump, a fecal pump or a long pole with a scoop device. Of course, mechanized pumping methods would be preferable.

Video: homemade concrete structure for a private house

Despite the fact that the process of manufacturing a septic tank is associated with certain time and material costs, in the future, built with your own hands treatment plant justifies itself more than once. You do not have to constantly think about the fact that the sewage system can “get up” at the most inopportune moment or take care of regular pumping out of the tank. The septic tank will be able to function for many years without polluting environment and without causing any problems.