Construction of cesspools from concrete rings. The types of such pits, their features, the choice of materials for construction and step-by-step work technology. A cesspool made of concrete rings is a round underground tank designed for the collection and disposal of domestic wastewater. Such a structure is indispensable in the absence of a centralized sewerage system in a country house. Today is our material on how to make a cesspool out of concrete rings.
Varieties of concrete cesspools
The main elements of such cesspools are concrete rings, which are mass-produced by precast concrete factories. Products give structures strength, tightness and durability. Reservoirs of two types can be made from concrete rings: sealed storage cesspools and pits with a filtering bottom.
For the owners of such structures, two points are important - the structure of the bottom of the pit and the frequency of disposal of sewage. Tanks of the first type retain the entire accumulated volume of sewage, so they have to be pumped out from one to two times a week. Users of other types of pits use the services of sewers less often, since the cesspool is filled more slowly. Part of its liquid penetrates through the drainage layer of the bottom into the ground.
At first glance, the option of a cesspool with a filter bottom is more acceptable. However, during the construction of such a pit, the following factors will have to be taken into account: the compliance of the structure with sanitary standards, the type of soil and the location of its aquifers. If there is a clayey soil on the site that will not be able to quickly absorb liquid, it is impractical to arrange a filtering bottom. The same applies to aquifers: if they are high, there is a risk of contamination of drinking water.
A good result can be obtained by combining both of the previous options. One pit can accommodate two chambers made of concrete rings, connected by an overflow pipe. The first chamber is sealed. It receives wastewater from the house and is purified by settling. Through an overflow pipe located at a height of about 2 meters, the liquid fraction of the effluent enters the second chamber with a filtering bottom. Through its sandy-crushed stone layer, the liquid penetrates into the soil, reaching 90% of the level of clarification. If such water is subjected to additional purification up to 98% with aerobic bacteria, it can be discharged into a reservoir or used for irrigation.
Features of cesspools from concrete rings
The sewage accumulator, made of concrete hollow cylindrical elements, is a technical well up to 3-4 m deep. When it is installed, 3-4 concrete rings are placed in the pit on top of each other, and then the seams are sealed.
The bottom element of the well can be monolithic or absent altogether. It depends on the type of cesspool. The top of the tank is equipped with a sealed lid with a neck and a hatch. The volume of the well is selected taking into account the number of drains per day.
The main advantage of a cesspool made of concrete rings is its affordable cost. For many, this becomes the reason for choosing the simplest structure instead of buying a more expensive, but multifunctional septic tank.
An ordinary cesspool is also suitable for those who live outside the city only in the summer or on weekends. In this case, there are relatively few effluents polluted with waste, and if regular pumping is organized, such a pit is quite a suitable option.
If the volumes of effluents are large, purchasing a septic tank will be the right decision. It costs more than an ordinary well, but it cleans up waste and protects the garden soil from pollution. Installation conditions for such a filtering structure: sandy soil, a low aquifer and a crushed stone layer at the bottom with a thickness of 1-1, 2 m.
Disadvantages of a cesspool from the rings, which may be the reasons for refusal to build: low quality of wastewater treatment, limited volume of the well, the need for its frequent pumping, an unpleasant smell spreading from the pit along the site.
Those wishing to build a filtering cesspool should be aware that periodically after pumping out the effluents, it will be necessary to clean, and eventually replace the crushed stone drainage of the bottom of the pit.
Attention! Sanitary standards prohibit the use of single-chamber filter cesspools with a volume of sewage in excess of 1 m3/day.
How to make a cesspool from concrete rings?
The construction of any tank has its own nuances, which may be associated with the location of buildings, soil and landscape features. We will consider a typical version of the construction of a pit from rings.
Preparation for work
Preparatory work includes the selection of a site for a cesspool, the purchase of materials and the preparation of tools.
According to SNiP, it is forbidden to arrange cesspools closer than 5 m from a residential building, 30 m from a water source and 2 meters from a neighbor's fence.
It is not recommended to locate the sump in a low-lying area in order to avoid flooding it with atmospheric precipitation. This can cause the pit to overflow and contaminate the soil with sewage. A convenient access to the cesspool should be provided no further than 4 m from the neck of the tank, into which the sleeve of the sewage machine is inserted when pumping out wastewater.
The volume of the concrete sump is calculated from the height and diameter of the rings. Therefore, it would be better to buy these products from a specialized company located near the proposed construction site. In this case, delivery of the rings will be cheaper.
Standard rings with a height of 0, 89 m and a diameter of 1 m are produced by all precast concrete factories. Due to the increased popularity of cesspools, these enterprises began to produce complete sets of products for their assembly. The set includes: a bottom product with a bottom, up to five standard rings, a narrow neck and a floor slab equipped with an opening for a technical hatch. Concrete rings can be solid wall and perforated. The cover and hatch must be purchased separately.
When choosing, it is recommended to give preference to concrete rings with a lock connection. It guarantees the greatest tightness and rigidity of the assembled structure. In addition to factory kits, other materials will be required for the construction of a cesspool from concrete rings:
- Connecting brackets;
- Joint sealant;
- Coating waterproofing such as bitumen mastic to protect the tank on both sides;
- Cement, gravel, screed sand and bottom filter.
Shovels, buckets, rope and a ladder are useful as tools and accessories for work. All this is necessary for lowering into the pit and excavating soil from it.
Digging a pit
This is the first stage of the main work. Excavation can be performed independently and free of charge, or with the involvement of a crew or an excavator for money. After the work of earth-moving equipment, the walls and the bottom of the pit will have to be leveled manually using shovels.
To install concrete rings, you will need a round pit that is 0.5 m larger in diameter on either side. This space is necessary for external insulation of the cesspool with the subsequent filling of the sinuses.
Before starting the installation of the rings, you should prepare the base of the pit and dig a trench from the selected building to the waste tank. It is important to remember that the sewer pipe should be laid with a slope to the sump of 2%, that is, 2 cm per 1 running meter.
Bottom device
When constructing a conventional storage tank, its bottom and wall must be impervious. For a concrete well, a factory part with a special groove for installing a ring is suitable as its sealed bottom part. Its installation should be carried out on a solid and level base. This "glass" is an alternative to concrete preparation of the base.
Another option is a screed device that can prevent the soil from settling under the weight of the rings. To prepare the working solution, you need to take four parts of river sand for a part of the cement. To increase the strength of the screed, you can add granite screenings in a ratio of 1: 6. The solution must be prepared in a suitable container, and then poured onto the bottom of the pit and leveled.
In order to prevent the screed from cracking during the drying process, it must be periodically moistened. After a week, it will be possible to install the bottom cesspool ring.
A more practical option for constructing a cesspool made of concrete rings, which can save a week of time, is to install a factory finished slab instead of a screed. It must be laid on the flat bottom of the pit, and then concrete rings are mounted on top of it in turn.
When constructing a filter well, the presence of a sealed bottom is not provided. Instead, it will be necessary to make a multilayer filter, which will retain the solid fractions of the effluents, and let the liquid fractions pass into the ground. The bottom layer of such a filter is sand, on top of it there is granite screening, and even higher is coarse gravel. The thickness of the underlying layers can range from 0.3-0.7 m, depending on the depth of the cesspool. The filter capacity in the reservoir barrel is 1-1, 2 m.
Anaerobic bacteria are often settled on crushed stone, capable of decomposing waste and cleaning it.
The filter and the underlay are replaceable elements. If they cease to fulfill their functions over time, they need to be replaced.
Installation of concrete rings
The first element of the well should be installed on the screed or concrete slab of the bottom of the excavation. The correctness of the installation of the cesspool from concrete rings must be checked at the building level. The absence of distortions further guarantees the verticality of the entire structure. After installing the first element, you must immediately install the second one on it and seal the seam with a sealant.
There are many different mastics with elasticity and high strength. Among them there are those that can be applied to joints that are already in the water. Others protect the concrete from the corrosive waste fluid environment. Sufficiently effective materials for internal sealing are:
- Hydro seals Waterplag, Peneplag, etc. During hardening, they increase in volume, overlapping any seams. The only problem is their high price.
- Hemp, jute ropes impregnated with fiber rubber from KIILTO FIBERPOOL.
- Sealing rubber bands RubberElast.
- Liquid glass to be added to mortar.
To insulate the outside of the cesspools, you can use coating materials and roofing material. For a continuous surface coating, such solutions as Antihydron, Bastion, etc. are suitable. Well-made insulation will ensure the safety of the cesspool for 30 years.
After sealing the seams, a sewer line must be introduced into the tank. To do this, an inlet hole must be made in the wall of the well 300 mm below the freezing point of the soil. After connecting the pipe to it, the junction must be carefully sealed. In the northern regions of the country, pipes that are located above the freezing point are insulated. Then, on the last concrete ring, you need to mount the neck and install the floor slab. In its factory version, a hole for the hatch device is provided. In addition to it, you will need a ventilation hole. It must be made in accordance with the pipe diameter.
The last stage of work is the backfilling of the pit sinuses. When it is completed, the ground around the structure must be carefully tamped.
How to make a cesspool from concrete rings - watch the video:
That's all. As can be seen from the description of the technology, the do-it-yourself installation of a cesspool made of concrete rings is simple and accessible to any adult. It is important to know that only compliance with technical and sanitary standards, competent calculation and, most likely, the help of installers can lead to success. Good luck!
