How a cesspool is built from concrete rings: diagrams + step by step guide

The design and purpose of the cesspool

Cesspools, like septic tanks, serve to collect sewage. But these are primitive structures that are not able to purify the liquid.

In storage tanks, waste only partially decomposes, unlike VOC, where effluents are divided into solid waste and liquid, which is further clarified and reaches a purity of 60-98%.

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A cesspool is the simplest variant of a storage sewerage point, which has recently been most often constructed from concrete or reinforced concrete rings.

The volume of the cesspool sewer well is calculated based on the number of people living in the house. A wide range of rings allows you to choose them for a storage device of any size

Concrete sewer wells, designed to perform the functions of a cesspool, are built by sequentially installing rings on top of each other

Rings for the construction of a sewer cesspool can be installed using construction equipment or manually

The modernized version of the cesspool involves connecting a well with a filtering bottom to it. In such a system, settled wastewater is disposed of into the ground, so that vacuum trucks are much less likely to be called.

With an increase in the components of an independent sewer system, the degree of wastewater treatment increases. In such structures, the first two chambers with a sealed bottom, the third - with a filter

No matter how many separate wells the sewer system includes, each of them is supplied with its own manhole for maintenance.

Cesspools made of concrete rings are filled up to the very hatch. Only by its presence it is possible to externally determine the presence of sewer wells on the site

Cesspool of concrete rings

Sewer facility for a large family

Modular construction principle

The use of small-scale mechanization

Organization of a cesspool with overflow

Three-dimensional sewer facility

Installation of a hatch over a sewer well

Sewer wells in the suburban area

All types of cesspools can be divided into two categories:

• sealed storage containers;
• drain pits with filter bottom.

For users, 2 differences are important - the device of the bottom of the tank and the frequency of waste removal. The first type retains the entire volume of sewage, so it is emptied quite often, once every 1-2 weeks.

For the second type of pits, vacuum trucks are called less often, since the tank fills up a little more slowly. Part of the liquid seeps through a kind of filter that replaces the bottom, and enters the ground.

Scheme of the simplest cesspool. Usually it is designed in such a way that the volume of the tank is sufficient, and the drain masses do not rise above the sewer pipe.

At first glance, the second option is more acceptable, but it is only suitable for processing gray wastewater, and a number of factors must be taken into account when constructing it:

• compliance with sanitary standards;
• soil type;
• presence and location of aquifers.

If the soil in the selected area is clayey, unable to quickly absorb water, there is no point in making a filter bottom. The same with aquifers - there is a risk of contamination and violation of the ecological situation.

There are many solutions for organizing cesspools: they build structures from bricks, tires, concrete. Concrete structures and ready-made plastic containers are considered the most reliable.

Concrete tanks, created by erecting formwork and pouring, are more difficult to build than analogues from ready-made rings, which we will dwell on in more detail.

Scheme of a drain pit with a filter bottom. The air intake is removed as high as possible so that the unpleasant smell characteristic of sewer storage tanks does not disturb comfortable living

A cesspool made of cylindrical concrete blanks in finished form is a well from 2 m to 4 m deep. Rings in the amount of 2-4 pieces are placed one on top of the other, sealing the seams.

The lower element, depending on the type of pit, may be closed or completely absent. Sometimes, instead of a finished factory blank, a concrete slab is placed on the bottom.

The upper part is made in the form of a neck with a technical hatch and a tightly closed lid.

The main storage part of the tank is buried by about 1 m, since the inlet sewer pipe must be below the freezing level of the soil. The volume of the container is selected, taking into account the number of daily drains.

Features and benefits of concrete rings

The advantages of reinforced concrete circles for the construction of treatment facilities appear when compared with other materials used for these purposes:

1. Red brick tanks require waterproofing of the inner and outer walls. Even with carefully done work, they are short-lived, destroyed by aggressive substances present in the drains.
2. The metal is subject to corrosion, especially in aerobic septic tanks under the influence of oxygen. The service life of black steel tanks is short, and stainless steel is expensive.
3. The main disadvantage of plastic is its light weight. Even filled with water, it can be squeezed out when the soil is heaving. Requires anchoring to a reinforced concrete slab. Eurocubes and plastic barrels have thin walls; protection with a metal frame is necessary so that the soil does not crush.
4. The construction of a reinforced concrete monolith is a laborious and long-term process.

Concrete ring construction: step-by-step instruction

A standard sewer storage tank consists of 2-3 rings. Each ring measuring 1x1.5 meters can hold up to one and a half cubes.

The construction of a cesspool from concrete rings is a multi-stage process that requires a certain sequence.

Step #1. Digging a pit and arranging the bottom

Having decided on the dimensions of the future "well", they dig a pit, the dimensions of which exceed the diameter of the installed rings by 80-90 cm. The walls of the pit are cleaned and leveled.The bottom of the pit is carefully rammed.

When constructing a filter structure, the bottom of the pit is lined with a 25-cm layer of fine gravel or broken brick

To equip the sealed bottom of the pit, cement is poured or bricks are laid on a pre-erected formwork, the dimensions of which correspond to the shape of the future tank.

The bottom with the formwork installed is laid out with several layers of bricks or poured with cement mortar. It takes 5 to 7 days for concrete to harden. To simplify their task, they use ready-made concrete rings already equipped with a bottom.

Step #2. The erection of the walls of the building

After the filled bottom has acquired the desired strength, proceed to the installation of concrete rings. Rings are sequentially lowered into the prepared mine well with the help of a winch or a crane. If during the dive the ring is warped and stuck in the ground, the hole should be slightly expanded.

When installing and adjusting the rings, in order to avoid distortions, the verticality and horizontality of the planes should be checked using the building level

To soften the blow and avoid the appearance of cracks in the concrete, boards are temporarily laid on the upper face of each ring. Concrete rings, if necessary, are tied with reinforcement and fastened together with steel plates or brackets. A more secure grip can be achieved by using rings with a "lock".

The joints are covered with cement mortar with the addition of liquid glass and waterproofed using old rubber seals.

To ensure waterproofing qualities, the outer surface of the installed rings is covered with bituminous mastic and wrapped with roofing material

After the installation of the barrel of the tank is completed, the voids between the outer walls of the erected tank and the pit are strengthened:

• stones;
• broken brick;
• soil dumped when digging a pit;
• construction waste.

In regions where the depth of soil freezing exceeds one meter, it is desirable to insulate the walls of the tank.

The pipeline to the cesspool is laid below the freezing point of the soil. To achieve the required slope, the pipes are laid in a trench using brick supports.

Step #3. Installation of the hatch and ventilation pipe

The upper ring is closed with a slab made of reinforced concrete. At the final stage, ventilation is installed, which will remove methane and explosive sulfuric gas resulting from decay.

For the construction of an outlet pipe, a meter-long cut with a diameter of 100 mm is taken and it is buried into the cavity of the well so that the upper end rises half a meter above the ground.

To prevent the spread of unpleasant odors, the cesspool is covered with a plastic waterproof hatch. It is installed on a neck with a height of 300-500 mm.

The inspection hatch must be equipped with two hermetically sealed covers: the first is placed at the level of the ceiling, and the second at ground level

The double lid will prevent the spread of an unpleasant odor in the summer and the freezing of the contents in the winter. To increase the insulating properties of the structure, the space between the covers is laid with cuts of mineral wool or pieces of foam.

A layer of clay is laid on top of the ceiling, on top of which decorative soil is poured at the level of the installed cover.

Install rings

The sewerage drainage device provides for the use of special equipment during installation, since the rings weigh quite a lot and it is very difficult to install them on your own. Their design has 4 fasteners that look like ears. These parts are used to lift them and are made of wire rod with a diameter of more than 6 mm.

An important component is the choice of the optimal approach to the performance of work and compliance with all safety rules. Lifting must be done for four ears at the same time

It is worth noting that the dimensions of the cables should be identical, and the whole process should take place without haste and jerks. The first thing we do is lower the ring exactly, and then the rest of the products.

We seal the entire structure and install the cover. Its installation is also carried out by a crane, and all the cracks are sealed in order to obtain the integrity of the device. After that, the cover is covered with earth.

So we examined the features of a sump made of concrete rings and its basics for its installation. As you can see, the process is not so complicated, you just need to connect special equipment. For the future, during operation, it will be necessary to periodically clean the pit.

The choice of the location of the cesspool

In order to prevent wastewater from getting into drinking water in case of leakage of the collection tank, the minimum distance between it and the house should be 8-10 m. The distance to the fence is also regulated - from 1 m.

Important! Cesspools without a bottom are allowed to be used with a wastewater volume of not more than 1 cubic meter per day. They are located 30 m from the nearest well or well

When choosing a place for a pit, it is imperative to take into account the possibility of a machine approaching for pumping sewage waste: a sewage treatment plant should be located at a distance of 4 m from the road. Unauthorized placement of such a pit outside your own site without the consent of utilities is prohibited.

Important! Violation of sanitary standards and the construction of a cesspool near residential buildings and drinking water intake, leading to a threat to human health or environmental pollution - a criminal offense (Article 250 of the Criminal Code of the Russian Federation)

Wooden formwork construction

Inner and outer formwork can be made from ordinary planed boards and plywood. The planed board is taken from 20 to 50 mm thick. It is better to take plywood thicker than 10 - 12mm.

The board will make up the body of the drum. It will be attached to knocked down or glued plywood rings.

First, 2 - 3 sheets of plywood are fastened together, the sheets are taken 300 - 400 mm more than the outer diameter of the ring. After that, a pattern is made from this blank with an electric jigsaw, for the external and internal contours of the formwork. When calculating, do not forget to take into account the thickness of the planed board with which the contour will be sheathed.

The contour is done 2, top and bottom. After that, both contours are sheathed with a prepared board and cut into sectors, for ease of dismantling after the structure has solidified.

Sectors of external formwork can be fastened with wooden planks or better with metal hoops. From the inside, the formwork is cut into 2 segments and removable strips 20–30 mm wide are made at the border of the segments.After hardening, the removable strips are removed and the segments of the internal contour are pulled out.

Arrangement of the tank: taking into account sanitary standards

Despite the fact that the process of building a cesspool is simpler than building the same septic tank, a number of certain nuances should be taken into account when building a structure. After all, the efficiency of the sewer system and the convenience of its use directly depend on them.

The place for the construction of the pit is chosen away from the house and sources of drinking water so that the drains seeping into the ground do not cause harm. It is necessary to provide for the possibility of accessing a sewage truck to clean the pit

Regardless of the type of design chosen, in order to properly make a cesspool, it is necessary to competently approach the place of its arrangement.

When determining the location, it is important to take into account the level of groundwater occurrence. If there is a possibility of infiltration of treated effluents into the intake horizon, the installation of an absorption structure will have to be abandoned

In addition, in regions with characteristic flood phenomena, it is impossible to build wells with filtration holes in the walls. Because there is a high probability of contamination of groundwater when a sewer facility is flooded during its seasonal increase.

The organization of the storage tank is also carried out according to special rules. A free access for sewage equipment, which in most cases is distinguished by impressive dimensions, should be provided to the buried drive.

The rules for placing cesspools are strictly regulated by SNiP. Failure to comply with the prescribed requirements is punishable by fines.

The cesspool is located at a distance of 4 meters from residential buildings, 30 meters from a water source, 5 meters from the road and 3 meters from garden beds and plantings (+)

When determining the dimensions of the structure, keep in mind that the maximum depth of the pit should not exceed three meters. Exceeding the depth greatly complicates the process of pumping wastewater.

In addition, the walls of the structure must be insulated to the depth of seasonal freezing of the soil, and a small protrusion should be provided in the upper part of the pit for installing the cover.