Septic tank for a summer residence and a suburban area: how to improve living conditions at the lowest cost

Recommendation points

• How a septic tank works
• Basic information about ready-made septic tanks
• Plastic septic tanks
• Metal septic tanks
• Concrete septic tanks
• We build a septic tank with our own hands from “eurocubes”
• Concrete septic tank casting
• Septic tank device from car tires
• Toilet in the country

This article will consider the problem of solving everyday issues familiar to every summer resident, namely: wastewater disposal. We offer several solutions, and which one is the most suitable – the choice is yours..

A modern dacha is no longer just a plot of land with a small house in which you can store garden tools and wait out the bad weather. City dwellers strive to spend all their free time in the clean air, indulging in conveniences. This raises the problem of wastewater disposal, since there is usually no centralized sewerage system. There are several ways to solve the problem, but it is difficult to avoid the expenditure of significant material resources. Consider several budget options to choose the most suitable.

How a septic tank works

In order for solid waste in wastewater to at least partially decompose, at least three days must pass, but the volume when selected is calculated from the water consumption during the day. If it does not exceed 1 m³ – a single-chamber septic tank is enough, at a higher flow rate (up to 5 m³) requires the installation of a two-chamber system, and if the water consumption is more than 8 m³ use a three-chamber septic tank.

Discharges that have entered the septic tank sink to the bottom, where they form a sludge layer. The liquid is poured through a pipe located in the upper part of the chamber into the filter well (at a flow rate of no more than 1 m³) or into filtration fields (at higher flow rates). After passing through the filtering layer of gravel, the drains go into the ground, where they are finally destroyed by anaerobic bacteria. Underground filtration fields work in the same way: their design is a system of pipes with many holes. At intervals of 5–8 years, they must be dug out, the contaminated filter layer removed and a new one should be put in its place. This work is estimated at about 10 thousand rubles.

The natural decomposition of effluents can be accelerated several times by using a special agent – a bioactivator. As a result of its action, waste water with solid waste decomposes into water and substances that can be used in the country as fertilizer. A half kilogram of bioactivator (worth about 750 rubles) is enough for 4 years for a single-chamber septic tank. The drug is simply flushed down the toilet monthly in the amount of two tablespoons. However, at least once every 5 years, the septic tank must be cleaned of sediment using a sewage machine. From this it follows that the treatment systems should be placed closer to the entrance gate..

Basic information about ready-made septic tanks

For the device of local sewerage, septic tanks are used – sealed underground tanks of a special design. They are made from polymeric materials, metal or concrete. For giving, as a rule, a single-chamber device is sufficient – it all depends on the amount of water used.

Plastic septic tanks

They are relatively cheap, lightweight and durable, so they are most often chosen for summer cottages. It is not difficult to deliver them to the site yourself. Such devices do not rust, are not afraid of rodents and can last 50 years or more. Single-chamber septic tank of this type (with a capacity of 2 m³) costs from 15 thousand rubles.

But the light weight of the structure is also a disadvantage: additional installation costs are required, associated with the need for rigid fixation in the ground. Otherwise, external pressure will force the container to the surface. To avoid this, a reinforced concrete slab is cast under the septic tank, to which it is pulled with the help of cables. This more than doubles costs.

Metal septic tanks

They cannot be forced out to the surface of the earth by the pressure of soil and groundwater. But they are susceptible to corrosion, and lifting equipment is required to transport and install them. They must be treated with bituminous mastic, which does not have the best effect on the ecology of the land. The cost of such single-chamber septic tanks with a volume of 2 m³ – about 20 thousand rubles, but taking into account other expenses, the costs increase significantly.

Concrete septic tanks

Also, like plastic, they are not afraid of corrosion and do not require additional fastening. The disadvantage of this design is the need to use special equipment at the stages of loading and unloading and transportation, as well as the need for processing with bitumen mastic to protect hygroscopic material from moisture penetration. A ready-made concrete septic tank costs about 20 thousand rubles, excluding the cost of delivery and installation. The advantage of this design is the possibility of its own production..

A factory-made septic tank is not a cheap pleasure. You can reduce costs if you build such a system yourself. It is worth considering three options for the design of a homemade septic tank.

We build a septic tank with our own hands from “eurocubes”

The first option is the arrangement of a system of so-called “Eurocubes” To do this, you need to purchase two plastic containers of 700 liters each: this volume is quite enough to support the life of two or three people. Eurocubes are connected in series with each other by pipes in their upper part, forming a modular system. The pipes in the holes are fixed with epoxy glue. You can additionally use silicone for sealing. It is necessary to provide for the installation of a gas outlet pipe: its outlet should be above the water level in the tanks, and the height should be at least 4 m..

“Eurocubes”, due to their shape, to a lesser extent than cylindrical containers, are forced out of the ground, but still need additional strengthening: they are tied to piles driven into the ground. The thickness of the walls of such containers is small: “Eurocubes” are not intended for digging into the ground. They can freeze and external pressure can destroy them. To avoid this, before backfilling, measures are taken to insulate and strengthen the containers. They are lined from the sides and on top with plates of extruded polystyrene foam and protected with flat slate or moisture-resistant plywood, which is additionally treated with rubber-bitumen mastic. Pipes should also be insulated..

The advantage of such a homemade sewage system is the ability to build it up as needed: with an increase in the amount of used water, you can increase the number of modules by connecting them together. The cost of one new Eurocube is about 3–3.5 thousand rubles. On the Internet and in newspapers, you can find many offers for the sale of used containers, they are about 20% cheaper than new ones and are quite suitable for use as septic tanks.

Concrete septic tank casting

The principle of the device of this design is no different from the above. First, you should prepare a pit, the size of which depends on the dimensions of the future septic tank plus about 0.5 m around the perimeter – for the convenience of processing with waterproofing agents and insulation. After the end of the earthwork, formwork is arranged from the plywood panels. The wall thickness must be at least 100 mm.

To avoid concrete leaks, the inner walls of the formwork are lined with plastic wrap or roofing felt. Subsequently, this will serve as additional protection from groundwater.

A welded mesh made of metal rods with a diameter of 5–8 mm is placed between the plywood sheets. To keep it centered, plywood should be drilled in several places and a wire bent in the shape of a hook should be inserted into the holes obtained. Hooking the mesh in several places, fix it.

The concrete is poured in several stages, but in one step. After each stage, it is necessary to compact the material using a vibrating nozzle on a drill or manually – using a metal pipe. Outside, the containers are insulated using the same high-density polystyrene foam, which is glued with cold rubber-bitumen mastic and processed from the outside. The pipes for connecting the modules are made of asbestos-cement, and the places of their entry are sealed with a cement-sand mortar. In order to obtain holes for entering pipes in the corresponding places of the concrete casting, special foam inserts should be provided.

The floor slab is cast separately. A regular plastic manhole cover is used as a cover..

Septic tank device from car tires

This is the cheapest option for a septic tank, but for a summer cottage it is quite acceptable. You just need to find a certain number of large diameter tires, preferably one type. Tires can be requested at a trucking company, at a tire fitting shop or in a mechanical column of an agricultural enterprise: there are always worn out slopes.

In a previously prepared hole, the tires are stacked on top of each other in a column. The gap between the walls of the soil and the slopes is filled with large rubble and broken brick. This is necessary to ensure a better outflow of fluid into the ground. A reinforced concrete slab with a hatch hole should be laid on top. An inlet pipe and a pipe for connection with another module are installed between the tires. Pieces of brick or rubble should be placed in the gap formed between the slopes: under pressure, the chambers will shrink and the gap will close. The use of plastic thin-walled pipes is undesirable: they may not withstand the pressure of soil and materials. Cast iron or steel are more suitable..

Toilet in the country

If the dacha is not used as a residential building, a conventional rural toilet is sufficient to provide amenities. A hand-held washbasin can be attached to the outer wall, and the used water can be directed into the drain pit using a container and a hose.

Of course, you can buy a modern dry closet, but it is not cheap. To reduce costs, it is necessary to use cheaper designs, for example, from the same tires as described above. A toilet (cesspool type) in this case is built on top of the floor slab.

Accumulative toilets have a smaller capacity compared to cesspools. For them, containers are used from an ordinary 10-liter bucket to 260-liter plastic tanks, in the side walls of which small holes are made to drain the liquid after the solid fractions have settled. Such plastic tanks are dug into the ground, and in order for the decomposition of waste to occur faster and not to emit unpleasant odors, a bioactivator is periodically poured inside..

In order to create comfortable conditions at the dacha or suburban area, you should only choose (based on the characteristics of operation) the most acceptable option from those proposed above and, rolling up your sleeves, get to work.