The optimal solution for organizing the treatment of domestic wastewater in private households is a monolithic concrete septic tank. To install it, you can attract a team or do everything yourself. This will further reduce the budget, agree? Materials for his device are easy to purchase in hardware stores.
We will tell you in detail how to build a monolithic septic tank. Let's figure out which option of a concrete treatment plant is better to choose for your site. Here you will learn how to care for an autonomous sewer system, what to do with sewage treated in a septic tank.
For independent home masters, we offer step-by-step instruction. A clear perception of information will provide useful schemes, collections of photos and video instructions.
Typical monolithic septic device
Standard concrete septic tanks for cottages and houses have from one to three adjacent chambers. Between them there is a movement of drains through overflow pipes mounted in partitions.
Due to multi-day sedimentation, separation of insoluble sediment from water and the activity of microorganisms, natural wastewater treatment occurs. All septic system chambers are used only for sedimentation.
Do not make the adjacent filter well. Over time, this will lead to deformation of the entire septic tank, so you need to install a filter system separately. It must be selected based on the area and the desired quality of cleaning.
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Single chamber storage design
Two-chamber septic system
Three-stone concrete septic tank
Factory-made concrete modules
It can be a free-standing well, a filtering trench or a filtering field. The purification system can be mounted after the installation of a monolithic septic system, but in this case the trenches will have to be digged manually. Using the equipment will be impossible, as it can damage pipes and ceilings.
The specifics of a single chamber cleaning station
A septic tank that has one chamber is called a drain pit. Its device does not involve multi-stage cleaning and serves primarily for the storage of sewage and subsequent pumping.
Pumping and transportation of waste is carried out using a special machine. The disadvantage of such a drainage system is its fast filling and costly maintenance.
In a single-chamber septic tank, the settled water flows into the sewer and is further treated in the filtration field or filter well. Solid fractions deposited to the bottom should be pumped out every 4-6 months
The depth on the scheme of this concrete septic tank is 2 m, it is designed to serve two to three people. Due to the lack of cleaning and draining, the tank quickly overflows.
An alternative to a monolithic single-chamber septic tank is a cesspool of concrete rings, we recommend that you familiarize yourself with the features of the structure.
Diagram of a two-chamber version
In this system, water undergoes preliminary sedimentation before discharge or pumping. According to sanitary standards, such water can be discharged into the ground. The advantages of this system are its compactness. With the same volume, two separate tanks made of reinforced concrete rings take up more space than a monolithic concrete structure.
The diagram shows the proportions of the septic system. The optimal size of the receiving chamber should exceed the volume of the second settling tank in a proportion of 1: 3 (+)
This septic tank has an internal partition made of concrete, which allows water to settle in two stages. In addition, it can be equipped with a sensor that signals an overflow.
The second overflow at the opposite end of the tank is located slightly lower than the first, which eliminates the return of effluents to the receiving compartment and provides spontaneous overflow of the settled liquid into the next chamber.
A two-chamber drainage pit needs to be pumped out once a year, a single-chamber pit - with a frequency of once every 3-6 months, i.e. 2-3 times more often. Two-chamber will require more construction costs, but in the long run, exceeding the budget will quickly pay off
How to build a two-chamber septic tank using concrete rings is written here. We recommend that you familiarize yourself with this material.
Necessary tools and materials
For the installation of a concrete septic tank with your own hands, you will need the following materials:
- ASG (2.5 t).
- Cement (18 bags of 50 kg each).
- Liquid bitumen (20 kg).
- Iron Corner 40 x 40 (25 m).
- A sheet of iron with a thickness of 2 mm 1.250 x 2.0 m (1 pc.).
- Plywood sheets 1.5 X 1.5 m (8 sheets).
- Flat slate 1500x1000x6 (6 L).
- Polyethylene film (two to three cuts with a total area of 13 x 9).
- Boards 40 x 100 mm.
- Plasticizer (depending on type per 5.9 cubic meters of concrete).
- Wire rod with a cross section of 0.6 mm (footage depends on the density of the mesh).
- Bars 50 x 50 mm.
- Bricks (120 pcs.).
- Pipes for external sewage (individually, depending on distance).
- Pipes for internal sewage (individually, depending on the design).
- Branch pipes (individually, depends on a design).
- Fittings (according to the number of pipe joints).
- Sealant (1 pc.).
- Screws (300 pcs.).
- Cutting disc for metal (1 pc.).
- Grinding nozzle for angle grinder (1 pc.).
To install a concrete septic tank, you will need the following tools and equipment:
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Mixing equipment
Hand tools for work
Grinding grinder
Drill and screwdriver for assembling formwork
Marking device
Scale Laser
Wheelbarrow for transporting various goods
All calculations of materials were performed for a monolithic concrete septic tank with the dimensions: width -2 m, length - 3 m, depth - 2.30 m.
Monolithic septic system device
The complexity of installation makes many people buy ready-made reinforced concrete structures. Their use allows installation much faster.
It will take a couple of days to organize a septic system of prefabricated elements, and for the installation of a monolithic concrete structure, it will take more than a month, including the construction of formwork and the technological break devoted to hardening of concrete stone.
Each stage, from excavation to welding hatches, is carried out in strict sequence. Before you begin to work, you need to stock up on time or agree on assistance with other people on a commercial basis.
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Preparing a foundation pit for a septic tank
Aroma frame construction
Construction of casting formwork
Formwork dismantling after 28 days
Installation of supports for the upper floor
Fill plane device
Organization of openings for hatches
Arrangement of necks for a septic tank
Since the pipe leaving the house / bathhouse and entering the septic tank must be laid with a standard slope, it is better to prepare a trench for it in advance. This is necessary to accurately determine the height of the pipeline entry into the concrete structure.
Excavation development and preparation
Since the pit will be used as a shape, it is necessary to make its edges as even as possible. Digging should be done without using equipment or using only at the initial stage.
You need to align the edges of the pit manually. Periodically check the surface for evenness. To do this, use the level. For even corners, periodically you need to measure with a building corner.
Excess soil should be removed or distributed evenly over the site. After completion of excavation, it is necessary to lay a plastic film at the bottom of the pit. It can consist of several cuts.
The film should cover the pit completely. The use of polyethylene performs two tasks. It reduces the consumption of cement mortar, and also serves as additional waterproofing. Joints of plastic sheets do not need to be sealed. The film can be fixed with bricks, so it will not move with strong gusts of wind.
To descend into the pit, you can put together a ladder from improvised materials. With significant recesses on the stairs, soil can be transported in buckets
Construction of formwork for pouring the mixture
The life of the entire structure depends on how the formwork is exposed. Since the volume of liquid will be contained inside the tank, it will exert pressure on the walls of the tanks. Therefore, before exposing the formwork, it is necessary to make reinforcement.
To do this, you can use reinforcement, knitting wire or already finished mesh. Reinforce the walls so that the grid is in the middle of the monolith. Its distance from the outer edges of the pit should be 7 cm.
After the walls, a mesh for the partition is mounted. It must be placed at a distance of 2 meters from the sewer pipe. There should be two compartments. Larger for primary settling, and smaller for secondary
After installing the partition, you can reinforce the floor. The mesh for him should be raised 7 cm from the bottom surface. This is necessary for the greatest bonding effect.
The construction of the formwork is done before the device of the reinforcing frame. To do this, from plywood and bars, you need to build shields. It should be two boxes without a bottom. Each is placed in a container.
Their sizes:
- for the first tank: width and length 1.7 m;
- for the second tank: width 1.7 m and length 0.085 m;
It is necessary to check that there are no gaps during installation. After organizing the formwork and before concreting, you need to make the installation of overflows. If you do this after concreting, you have to hammer holes. This can lead to structural deformation.
Installation of overflow pipes
For overflows, two straight nozzles are required. The first pipe is put on a sewer pipe leaving the house. To do this, cut a suitable hole in the plywood and bring the end to the receiving tank
The pipe is attached to the pipe with a rubber ring and sealant. The drain hole of the nozzle should face down.
A pipe 40 cm long must be inserted on the partition between two containers. The pipe is fixed in plywood on both sides of the containers. On the ends of the pipe on both sides of the pipe fittings directed downward drain holes.
Preparation and pouring of concrete mortar
Since the thickness of the layer is small (15 cm), it is necessary to make a strong solution. First you need to take a container for mixing the solution. At its bottom, put cement and ASG, in a ratio of 1: 3.
The amount of water depends on the moisture content of the gravel mix. The consistency of the solution should be moderately thick. To improve the properties of the solution, you need to use a plasticizer. The amount of its addition depends on the brand of cement.
For the convenience of pouring cement into narrow gaps between the formwork and the plastic film, you can use a gutter made of metal, a half pipe or a gutter. This will evenly fill the solution, avoiding the formation of cavities
So you can speed up the filling process. It is better to fill the entire volume in one day. Such monolithic concrete will last longer, since there will be no delamination in the cement stone along the pouring border on different days.
You can start with walls or floors. This is not of particular importance. After the completion of concrete work, you need to wait until the mortar has completely set and solidified. For this, according to construction standards, 28 or several more days.
The curing rate depends on the ambient temperature. When dried, the concrete changes color and becomes lighter. The construction poured into the formwork must be protected from drying out with wet sawdust or polyethylene.
Freezing of cement stone during hardening should be completely excluded. At the end of the specified period, the formwork can be dismantled.
Top floor device
Installation of the upper floor begins with the exposure of the frame.
It consists of iron corners, which are installed in the following lock:
- Four corners 3 meters long, you need to lay on the walls of the septic tank. One corner from each edge and two close to each other in the middle of the tank.
- Several transverse corners are stacked on top, forming a lattice. They need to be stacked taking into account the sizes of future hatches.
The resulting design needs additional fastening. To do this, make holes in the corners and use anchors to attach them to the concrete base. Cross corners must be attached with bolts or special screws.
After mounting the corners, it is necessary to cut suitable squares from the flat sheet slate. After that, the slate sheets need to be laid on top of the grate. To prevent the flow of the solution, it is worth treating the joints with liquid bitumen.
Next, you need to fence the perimeter of the hatches with boards. Better to make them contiguous. In addition to hatches, additionally set the formwork over the entire floor area. After that, you need to insert the ventilation pipe, making a hole in the slate above the second chamber.
Upon completion of the installation of the pipe, it is possible to fill in the overlap area with the solution. After drying and hardening of the solution, the formwork must be removed.
The empty space for hatches must be covered with bricks, so that they do not rise above the surface. The mortar for bricklaying needs to be done without filler, using cement and sand
Since the amount of sand required is small, you can sift the ASG. The proportions of the solution can be done 1: 4. After masonry, it should harden. It takes 2-3 days. After waiting for this period, you can warm and bury the pit. Periodically, you need to tamp the soil.
Manufacturing manhole covers
In order to prevent overcooling of the septic system and the ingress of debris into it, it is necessary to install hatches. Covers for them can be made of wood and metal. The wooden lid is installed as the inside.
It protects against temperature differences, and a heater is placed on it. For its manufacture, you can use plywood or individual boards, knocked together. The cover does not need to be mounted on awnings, it must be removable.
The outer cover must be made of metal. To do this, you need a building angle (40x40). A rim for the hatch is welded from it, which is attached to the base using anchors.
According to the size of the rim of the sheet of metal, you must cut the cover. Edges need to be processed with a grinding nozzle for angle grinder. Awnings must be attached to the cover. They can be welded or bolted. After that, the cover is attached to the rim in the same way.
For the necks of a homemade septic tank, you can make two or one common lid from the board. It will have to be changed periodically. The area around is filled with soil, and the lid is closed with water-repellent material
Proper septic system care
During operation, any sewer pipes are periodically coated from the inside with greasy coating, which reduces their throughput. It must be removed by special means.
They can be chemical or bacterial. Means based on microorganisms are preferable, since they do not spoil the pipes and do not lead to the death of microflora inside the septic tank.
In winter, when the temperature drops to -25 degrees Celsius, it is necessary to insulate the holes of the hatches. Otherwise, the processes of processing organics in containers will slow down, which will lead to a decrease in purification.
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Absorption well in tertiary treatment
Installation of filter cartridges
Filtration field for soil treatment
Disposal through a filtering trench
How to use treated drains?
The water purified and disinfected in a septic tank can be used to organize the irrigation of plants and trees in a personal plot. It has a small percentage of pollution (10 -15%).
Purified water is quite suitable for use in household purposes. This will significantly reduce water consumption for the organization of irrigation of the garden or garden in the summer. That means it will save money.
The use of pumping equipment involves power consumption. To provide power, you can use a small battery and a battery
For a couple of years of operation, the system will fully pay for itself, since with the help of solar energy converted into electricity, it is possible to reduce the consumption of electricity supplied by centralized networks. The solar battery is quite able to cover the needs of the pump.
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Sewage treatment tank
Sewage disposal gutter
Landfill waste water disposal
Watering non-agricultural plants
The pump can pump water from a secondary or tertiary sump, as well as excess sludge from the receiving chamber. Pumped sludge can be used in ripening compost. It is used as a standalone fertilizer or as a mixture with other components.
In the compost pit, you can pour the remains of organic matter. It can be fallen leaves, weeds and manure. After three to four years of rotting, an excellent fertilizer is obtained that increases the fertility of the soil in the garden.
The first video shows the principle of the construction of a concrete septic tank before pouring with cement mortar:
The second video shows the pouring stage, the dismantling of the formwork and the final form of the septic tank:
This is one of the most budget options. Its manufacture is cheaper than the concrete analog of the rings, not to mention the prefabricated biological treatment plants. The price gap is more than 50,000 rubles, including installation.
Another design advantage is durability. Concrete does not decompose, but is partially destroyed by moisture. This can be avoided by treating the walls of the tanks with liquid waterproofing materials.
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