Today, many townspeople acquire suburban land plots for growing natural products, rest from the gray city bustle and even permanent residence in the green zone they have created. But, if in the city all the benefits of civilization are provided by utilities and energy companies, then on the garden plot, the owners themselves have to take care of the energy supply, the availability of water and the disposal of waste. And, of course, latrines are built first. And since many townspeople do not want to give up urban comfort in their summer cottages, in addition to latrines, various septic tanks are installed, which will be discussed in this article.
The simplest and cheapest version of a septic tank in the country is a cesspool filtering pit. Those. "Convenience on the street." This septic tank is arranged like this: an ordinary pit is dug up to a depth of 1-2 meters, its walls are strengthened with wooden formwork, or coated with clay. Sometimes metal barrels or old car tires are inserted into such a pit. A wooden structure is installed on top, which serves as a toilet. Liquid falling into this hole goes into the ground, and solid particles remain and accumulate over time. The advantages of such a structure are simplicity and low cost. Cons - such a pit needs to be cleaned by hand at least once every 3 months. In addition, dirty water that is absorbed into the soil worsens, over time, the ecological purity of the site.
Cesspool with a pipe
An improved version of the cesspool filter pit is a cesspool connected to the house by a sewer pipe. The walls of this pit are reinforced with concrete rings (without sealing the joints) or brickwork (with gaps, for better water penetration into the soil), the bottom is also not covered with anything. But the depth of such a pit should be no more than 3 m, otherwise there is a risk of infecting groundwater. From above, such a container is covered with a concrete or metal lid with holes for a ventilation pipe (it is better to make it taller than human height, then the smell of sewage will be much less felt) and for a manhole cover through which it will be possible to pump out sewage with sewage equipment. The advantages of this design are that it is more comfortable (the toilet is in the house and the sink has a drain into the sewer), it is cleaned less often than the "convenience on the street" and not by hand. Cons - the same violation of the ecology of the garden area and unpleasant odors on the site, characteristic of sewage drains.
Sealed pit
A sealed sump is a device that makes the sump even more perfect. The name speaks for itself. This means that a sealed container is buried in the ground, made of concrete rings with a bottom poured in concrete and sealed joints, or a plastic reservoir, which is also connected to the living space by a sewer pipe. Only this system no longer lets wastewater into the ground. This means there is no risk of contaminating the soil and groundwater. Such a container is closed with a sealed lid, into which a ventilation pipe is inserted to remove unpleasant odors. Sewage is pumped out of such a container using sewage equipment.
The advantages of such a system:
sanitary safety and the absence of the possibility of contamination of the environment with harmful bacteria;
the installation of a sealed cesspool does not depend on the depth of groundwater and on the type of soil on the site;
the absence of an unpleasant smell on the site (however, if the drive is made in the form of a well, then the smell is possible).
Minuses:
the cost of the tank itself and its installation is much higher than that of other types of cesspools;
regular expenses for sewage equipment.
Septic tanks with soil post-treatment
Another type of septic tanks installed in summer cottages is systems with soil aftertreatment of sewage effluents. Sewerage cleaning in such septic tanks is carried out due to the oxygen-free decomposition of harmful substances by anaerobic microorganisms, followed by filtration of the purified water with sandy or sandy soils. Such a structure consists of three or four tanks, each of which performs its own purification function. The first tank is sealed and designed for rough cleaning of sewage, where the heaviest substances are deposited. Lighter particles are poured into the second and then into the third container (if provided). They are also sealed. In each tank, the sewage liquid undergoes anaerobic cleaning, in which special bioadditives decompose harmful substances. These bioactivators are commercially available (for example, Dr. Robik or Biosept). In order to add such a drug to the container, you do not need to open it; it is enough to flush a portion of this substance into the toilet twice a month. These tanks are made of concrete, brick, plastic or metal containers connected by sewer pipes. Ready-made cleaning systems with built-in reservoirs, for example, Tank, are also on sale.
After the sewage liquid has passed through all the tanks with anaerobic biological treatment, the final stage of treatment follows - overflow of most of the treated water into the filtration field, into a filter well or other soil treatment facility. As mentioned earlier, the filter in the drainage field must consist of sandy or sandy loam soils that pass water well, otherwise the water will be poorly drained and purified.
Advantages of the system with soil post-treatment:
cleaning septic tanks with sewage equipment is performed quite rarely - once every 1-2 years with the permanent residence of three people;
high efficiency of water purification (95-98%);
ease of maintenance and non-volatility.
Minuses:
constant purchase of bioactivators;
rather high cost of assembly and installation (from 30 to 70 thousand rubles);
at a high level of groundwater or on clay soil, such systems cannot be built, since soil filtration under these conditions is ineffective.
Septic tanks with biological treatment
Septic tanks with deep biological treatment are installed in any soil and regardless of the level of groundwater, i.e. in any conditions. These systems do not need to be designed by yourself - they are manufactured in an industrial setting and are sold ready-made. It remains only to connect such a device to the sewer. The principle of sewage treatment with a biological treatment system is identical to the operation of a septic tank with soil additional treatment: wastewater is also poured from one chamber to another, passing through several stages of treatment. Only in this version there is no cleaning of the liquid with soil, but a more thorough decomposition of harmful substances with the help of aerobic bacteria occurs - in the first chamber, the sewage liquid is divided into heavy (insoluble) sediments, which remain at the bottom, and lighter ones, which are poured into the next tank and are exposed to there processing anaerobic and aerobic bacteria. But in order for these bacteria to effectively decompose harmful substances, special devices are connected to the system - aerators, which saturate the medium in the container with air.
In the third chamber, the process of settling the liquid purified in the first two reservoirs takes place.It is divided into heavy suspensions, which sink to the bottom and form a sediment in the form of activated sludge, which is used as an excellent organic fertilizer and into clean water, which is removed from this tank through a pipe located much above the sludge level. Such water corresponds to the technical quality and can be used for household needs (for example, for irrigation of the site) or, without harm to the environment, be discharged into any water body or into the soil.
For the price, a biological treatment system is more expensive than a septic tank with soil post-treatment. But, if we take into account the cost of installing individual tanks and creating a filtration field in the soil post-treatment system, then the absence of these works in the installation of a biological treatment station equalizes the cost of these systems.
Advantages of septic tanks for deep biological treatment:
high level of sewage liquid purification (up to 99%);
complete absence of unpleasant odors;
simple and quick installation - the biological treatment station is sold ready for use. It remains only to dig a pit under it and attach it to the sewer pipe. It takes 1-2 days, no more;
This septic tank does not require constant maintenance, it works by itself, and solid sediment accumulates very slowly, therefore, the tanks are cleaned every 5-8 years.
The disadvantage of this system is its complete volatility. Without electricity or in areas with unstable electricity supply, a deep biological treatment plant is useless.
Comfort in the country is a relative concept. If you visit your land plot only during the summer season, and then only on weekends, then there is no point in talking about expensive septic tanks and comfortable plumbing, it will be a waste of money. But if you are going to live at the dacha all the time, then the “amenities on the street” after the city comfort are rather unnerving. I would like to make my place of residence comfortable and civilized. But it takes money. As they say, think for yourself, decide for yourself whether to have or not to have.
