In most cases, sewerage in the country is not provided. Instead, a cesspool is used. There are quite a few options for its construction, and each has both its advantages and disadvantages. Next, we will consider in detail the typical designs of cesspools and analyze the methods of their installation.
What is a drain pit and why is it needed
A drain pit, or as it is also called a cesspool, is necessary for private houses that do not have a direct sewer supply. The right drain pit recycles waste, allowing some substances after processing to soak into the ground without harm to it.
The popularity of this type of treatment plant is due to the ease of installation and the speed of work. One person without assistants is able to complete all the work within 3-5 days, depending on the type of construction.
On the other hand, there are certain difficulties associated with the further operation of the cesspool. First of all, this concerns the issue of pumping sewage. Equally important is the correctly selected volume of the pit.
Drainage pit device
The simplest designs that are most often found in rural houses and simple summer cottages are digging into the ground an old barrel or tank that has served its time. Such a design will allow for the collection and partial filtration of wastewater, provided that their daily amount does not exceed 1 m³. Such schemes have not received approval from the sanitary services, as they can harm the environment.
The simplest drain pit in a private house is a simple design. Through the sewer pipe, although direct flow is often encountered, sewage enters a container, the bottom of which is covered with silt. The drain pit should be equipped with a gas outlet pipe through which methane generated during waste processing will go outside.
Such a system is completely unsuitable for those houses in which permanent residence is planned. Taking into account the fact that the average daily water consumption for a family of four is up to 1 cubic meter, this leads to the need for frequent cleaning of the cesspool, and, accordingly, to financial costs. Previously, a ubiquitous method of removing sewage into the soil with their subsequent natural filtration was widespread, but in the current realities, this method, for obvious reasons, is prohibited by the sanitary service.
However, such a design is quite common, and will not have any special alternatives for suburban areas with infrequent attendance. It is easy to equip it on your own, but you need to consider the following points:
- The walls of the pit will require strengthening, as the water will gradually collapse the structure. To prevent this, they install a tank, or they build walls of brickwork or concrete rings.
- The volume of the cesspool should be at least three cubic meters. The correct calculation is made taking into account the fact that each person will need at least one cubic meter of space.
- Installed ventilation will increase the rate of waste recycling.
- If an overflow pit is being equipped, then it practically does not need to be cleaned, since its design assumes the presence of several chambers for waste processing. In this case, sewage enters the first chamber, in which they accumulate. After the level of sewage reaches the overflow partition, they will flow into the second pit and there they will already be absorbed into the ground. The solid waste remains in the first pit and is processed by the bacteria.
Types of drain holes
According to the type of execution, cesspools are divided into:
- concrete storage,
- brick,
- with a receiving container
- temporary
- with timber formwork,
- without a bottom, with the output of waste moisture directly into the ground.
We make a drain hole from concrete
It is a pre-fabricated solution for receiving sewage and has the following advantages:
- Construction speed. In fact, with a set of factory-made concrete rings, such a structure is built in one day. There is only one drawback - you will need a crane or an excavator to work.
- Reliability and durability of concrete.
- Minimum installation complexity.
Such a structure is being erected quickly:
- First, a hole of the planned depth is dug.
- The site is then levelled.
- Using a crane, the first ring is installed.
- The soil from under the ring is evenly removed, while exposing signal supports that prevent the structure from skewing.
- After the second ring was installed on the first ring, they are fastened together with metal brackets.
The installation is continued in the same way to the planned depth.
When all the rings have been placed, a concrete floor is installed with the help of a crane with holes made in it for the hatch and the ventilation pipe. The finished structure should rise above the ground at a level of at least 30 cm.
To provide it with better tightness, all seams and the junction with the sewer pipe are carefully sealed with bituminous mastic.
The problem of the hermetic design will be its rapid filling, and the need for frequent calls for sewage services, which will pump out sewage. In the same case, if the withdrawal of water into the ground is allowed, then rings with holes made are purchased. The installation technology is no different from the above.
In order to give the finished structure a more complete look in terms of aesthetics, it is necessary to sprinkle with earth the part of the drain system protruding above the soil surface, while providing planting with plantings that will perform a decorative function. For example, planting a Moorish lawn that is undemanding to the conditions will make it possible to turn a purification plant into a flowering flower bed. 
Brick drain hole
According to experts, the best option would be to use ceramic bricks, which will ensure the strength and durability of the structure. The process of building a drain pit made of bricks is conditionally divided into several stages:
- in a hole dug to the required depth, a drainage layer 20 cm thick is placed, consisting of sand and crushed stone of different fractions,
- after that, they begin to build walls, laying bricks in a checkerboard pattern, taking into account a gap of 5 cm between them for better filtration of waste substances,
- on all sides, bricks, as the masonry grows, are lined with crushed stone of large fractions,
- in the masonry make the necessary clearance for inserting a sewer pipe.
There are often conflicting recommendations about the final step. For example, to reduce costs, it is proposed to perform masonry half a brick thick, but it is important to remember that such a design will hardly take the weight of a concrete closing cover.
The design itself provides for two options for laying bricks:
- down to ground level
- 80 cm below ground level.
In the case of laying bricks to ground level, space must be left, taking into account the thickness of the closing cover made of concrete. The recommended construction with the completion of masonry, not reaching the ground by 80 cm, raises some doubts about its appropriateness for a number of reasons:
- since the design will require the installation of a closing cover, in the end the drain will still be deepened into the ground by at least 50 cm - which is dangerous by a possible fall into the pit,
- it is advised to fill the cover with earth to the surface level, but in this case either access to the hatch will be blocked, or another pipe of a larger diameter than the dimensions of the cover will have to be mounted on the installed cover - and in this case the system will be subjected to additional load.
Masonry is inferior to concrete in a number of factors:
- a concrete structure is erected much faster and ultimately requires less funds for construction,
- brick is more susceptible to moisture,
- to evenly distribute the load on the walls, the cesspool should have a cylindrical shape.
The expediency of erecting brickwork is manifested only when it is not possible to call heavy trucks.
Receiving containers made of plastic
If the question of how to make a drain pit without resorting to special costs is acute, then you need to pay attention to the option of installing a polymer tank of the required capacity. In this case, all work boils down to the fact that the required amount of earth is dug under the tank, and then the collection is placed in a prepared hole. After that, the remaining space is filled with soil. It is important to remember that sealed structures necessarily require the installation of a gas outlet.
Among the advantages are the following:
- ease of construction
- minimum costs in terms of labor intensity,
- protection of the air from the release of unpleasant odors,
- the durability of the polymer material, which is up to 50 years,
- during use, no waste substances enter the soil.
Of the minuses, you need to pay attention to the need for periodic pumping of sewage and the small capacity of the tank, so this option is optimal for use in low load conditions. For example, if the cottage is visited once a week, and a small amount of waste goes into the drain pit.
Temporary drain holes
They are made from used car tires. It is important to consider that the inner diameter must be at least a meter, otherwise the pit will quickly become clogged with sewage. In fact, the construction is easy to build: a hole of the required depth and diameter is pulled out, after which it is filled with tires, laying them one on one to the ground level.
Among the advantages of the design are the following:
- ease of work
- low price of waste tires,
- after laying, the empty space is filled with earth, and no additional finishing is required.
It is worth remembering that the design is suitable for a toilet placed outside and not connected to the house by a sewer system. Since it is assumed that the load on the pit will be negligible. Despite its name, with infrequent use, such a pit will last up to 25 years.
Drainage pit with timber formwork
Like the previous design, the use of wood is suitable as a temporary solution. In fact, this option is still sometimes used in rural areas and in some summer cottages, but due to the fact that wood, even with high-quality processing, will not withstand more than ten years, it makes little sense to use wooden formwork. Nevertheless, this is a drain pit, the price of which will be the most acceptable and will not exceed 3000-4000 rubles.
Of course, the speed of erection and isolation of the soil from sewage are the advantages of the design, but nevertheless, it is inferior to all varieties of the cesspool and for the most part serves as a relic of the past.
Drain hole without a bottom
It is a cesspool constructed of bricks, with the difference that the bottom of the drain is not processed. In some cases, the bottom is covered with a metal mesh, but in a chemically aggressive environment, it quickly rusts and loses its suitability. Impurities evenly fall into the ground, but due to the strong silting of the bottom of the pit, additional cleaning is periodically required.
In addition to the above, when arranging a cesspool, you need to pay attention to some tips to increase processing efficiency and ensure greater durability of the structure:
- Drainage of the bottom of the pit is best done using coarse gravel to prevent premature silting. The layer thickness must be at least 10 cm.
- To improve drainage, asbestos pipes are inserted at the bottom, which are installed with a ledge at a level of 50 cm from the bottom.
- It is better to finish the walls with clay to reduce the concentration of harmful substances entering the soil.
- In the event that there is one cesspool on the site, but its volume is not enough, it is more expedient to arrange another one nearby and connect the PVC pipe to the first one. In this case, the structure will become overflow and will need to be cleaned much less frequently.
- From the first moment of use, it is necessary to use special preparations containing bacteria. They speed up the natural recycling process and reduce odor.
- The overlap should extend above ground level so that in the event of heavy rain, the drain pit does not overflow with water and its contents do not fall into the area.
- In any embodiment, the design must include a chimney to remove accumulations of methane and other hazardous substances.
- Inorganic substances, including low-quality toilet paper, can significantly reduce the life of the structure and contribute to heavy silting of the surface.
Loading...