An urgent question that torments everyone who wants to live in private country houses without the ability to connect to a central water supply and sewerage system, how to make an autonomous sewage system. Indeed, without it, it is not possible to fully use such benefits of civilization as a bath, shower, kitchen sink, washing machine and much more. Sewerage in a private house can be equipped in different ways, which we will talk about in this article. Choosing the right system for your individual conditions and needs is even more important than bringing it to life..
The option of arranging a drainage system in private houses is selected depending on several conditions:
- House with permanent or temporary residence.
- How many people permanently live in the house.
- What is the daily water consumption per person in the house (depends on the number of water consumers, such as a bathroom, shower, toilet bowl, sink, washbasin, washing machine, etc.)
- What is the level of groundwater.
- What is the size of the site, how much space can be used for treatment systems.
- What is the structure and type of soil on the site.
- Climatic conditions of the area.
More detailed information about the requirements can be found in the relevant sections of SanPin and SNiP.
Conventionally, all sewage systems in a private house can be divided into just two types:
- Accumulation systems (cesspool without a bottom, sealed waste container).
- Wastewater treatment plants (the simplest single-chamber septic tank with soil cleaning, two-chamber septic tank – overflowing wells with natural cleaning, two-three-chamber septic tank with a filtration field, a septic tank with a biofilter, a septic tank (aerotank) with a constant air supply).
The most ancient, proven for centuries and even millennia, way of arranging the sewage system is a cesspool. Still some 50 – 70 years ago there was no alternative to this method. But at the same time, people did not use such a large amount of water in private homes as they do today..
A cesspool is a well without a bottom. The walls of the cesspool can be made of bricks, concrete rings, concrete or other material. Soil remains at the bottom. When sewage from the house enters the pit, more or less pure water seeps into the soil, clearing itself. Fecal matter and other solid organic waste settle at the bottom, accumulating. Over time, the well fills up with solid waste, then it must be cleaned.
Previously, the walls of the cesspool were not made waterproof, then when filling the hole they simply buried it and dug out a new one elsewhere.
I would like to note right away that a sewage system in a private house using a cesspool is possible only if the average daily volume of wastewater is less than 1 m3. In this case, soil microorganisms that live in the soil and feed on organic matter have time to process the water that penetrates into the soil through the bottom of the pit. If the volume of effluent is more than this norm, the water does not undergo sufficient purification, penetrates into the soil and pollutes the groundwater. This is fraught with the fact that wells and other water sources may be contaminated within a radius of 50 m. The addition of microorganisms to the cesspool somewhat reduces the unpleasant odor emanating from it, and also speeds up the process of water purification. But still, not worth the risk.
Output. A cesspool without a bottom can be built if the house is visited 2 – 3 days a week and does not consume a lot of water. In this case, the groundwater level must be at least 1 m below the bottom of the pit, otherwise contamination of the soil and the water source cannot be avoided. Despite the lowest cost of arrangement, the cesspool is not popular in modern country houses and cottages..
On the site near the house, a sealed container is installed into which sewage and waste from all over the house flow through pipes. This container can be off-the-shelf, store-bought, and made of plastic, metal, or other material. Or it can be mounted independently from concrete rings, the bottom is made of concrete, and the cover is made of metal. The main condition for installing a sewage system in a private house of this type is complete tightness. Corrugated pipes pragma are suitable for sewerage.
When the container is full, it must be emptied. To do this, a cesspool machine is called, the call of which costs from 15 to 30 USD. The frequency of emptying the tank, as well as the required volume, depends on the amount of waste. For example, if 4 people permanently live in the house, use a bathroom, shower, sink, toilet, washing machine, then the minimum volume of the storage tank should be 8 m3, it will have to be cleaned every 10-13 days.
Output. A sealed cesspool is one of the options for how you can carry out sewerage in a private house if the groundwater level in the area is high. This will completely protect the soil and water sources from possible pollution. The disadvantage of such a sewage system is that you will often have to call a sewer truck. To do this, from the very beginning, it is necessary to correctly calculate the place of installation of the tank in order to provide a convenient access to it. The bottom of the pit or container should not be deeper than 3 m from the soil surface, otherwise the cleaning hose will not reach the bottom. The lid of the container must be insulated to protect the pipeline from freezing. For a similar sewage system in a private house, the cost depends on the material of the container. The cheapest option would be to purchase second-hand eurocubes, the most expensive is concrete filling or brick. In addition – monthly cleaning costs.
A single-chamber septic tank is not far from the cesspool, very often it is called that. It is a well, at the bottom of which crushed stone is covered with a layer of at least 30 cm, and on top of coarse sand with the same layer. Wastewater flows through pipes into a well, where water, seeping through a layer of sand, gravel, and then the soil, is purified by 50%. Adding sand and gravel improves the quality of water purification and partially faeces, but does not fundamentally solve the problem.
Output. Conducting sewerage in a private house using a single-chamber septic tank is impossible with permanent residence and large volumes of drains. Only for houses with temporary residence and low water table. After a while, crushed stone and sand will need to be completely replaced, as they will silt.
As one of the economical sewerage options that can be assembled independently, the arrangement of overflow settling wells and filtering wells is widespread..
This sewerage system in a private house consists of two wells: one – with a sealed bottom, the second – without a bottom, but with powders, as in the previous method (crushed stone and sand). Waste water from the house enters the first well, where solid organic waste and feces sink to the bottom, fatty ones float to the surface, and more or less clarified water is formed between them. At a height of about 2/3 of the first well, it is connected to the second well by an overflow pipe, located slightly at an angle so that water can drain there without hindrance. Partially clarified water enters the second well, where it seeps through the powder of crushed stone, sand and soil, it is purified even more and leaves.
The first well is a sump, and the second is a filter well. Over time, a critical mass of faeces accumulates in the first well, for the removal of which it is necessary to call a sewer truck. This will have to be done about once every 4 to 6 months. To reduce the unpleasant odor, microorganisms are added to the first well, which decompose the feces.
Overflow sewerage in a private house: photo – example
A two-chamber septic tank can be made independently from concrete rings, concrete or brick, or you can purchase a ready-made (plastic) one from the manufacturer. In the finished two-chamber septic tank, additional cleaning will take place with the help of special microorganisms.
Output. It is possible to install a sewerage system in a private house from two overflow wells only if the groundwater level, even in a flood, is 1 m lower from the bottom of the second well. The ideal conditions are sandy or sandy loam soil on the site. After 5 years, the crushed stone and sand in the filter well will have to be replaced.
We turn to the description of more or less serious cleaning systems that allow you not to worry about environmental pollution..
This type of septic tank is one container, divided into 2 – 3 sections or several separate well containers connected by pipes. Most often, having decided to equip just this type of sewage, a factory-made septic tank is purchased.
In the first tank, wastewater settles, as in the previous method (settling well). Through the pipe, partially clarified water enters a second container or section, where anaerobic bacteria decompose organic residues. Even more clarified water enters the filtration fields.
Filtration fields represent the area underground where wastewater is treated by soil. Thanks to the large area (about 30 m2), the water is 80% purified. The ideal case is if the soil is sandy or sandy loam, otherwise you will have to equip an artificial filtration field from rubble and sand. After passing through the filtration fields, water is collected in pipelines and discharged into drainage ditches or wells. No trees or edible vegetables should be planted above the filtration fields, only a flower bed is allowed.
Over time, the fields become silted up, and they need to be cleaned, or rather replaced by gravel and sand. You can imagine how much work will have to be done, and what your site will turn into after that.
Output. Laying a sewage system in a private house, assuming the presence of a filtration field, is possible only if the groundwater level is below 2.5 – 3 m. Otherwise, this is a rather constructive solution, provided there is sufficient free space. Also, do not forget that the distance from the filtration fields to water sources and residential buildings should be more than 30 m..
A deep cleaning station allows you to perform a full-fledged installation of a sewage system in a private house, even if the groundwater level is very high.
The septic tank is a container divided into 3 – 4 sections. It is better to purchase it from a trusted manufacturer, after consulting with professionals for the required volume and equipment. Of course, the price for such a sewage system in a private house is not the lowest, it starts from 1200 USD..
In the first chamber of the septic tank, the water settles, in the second – the decomposition of organic matter by anaerobic microorganisms, the third chamber serves to separate water, since in the fourth one decomposes organic matter with the help of aerobic bacteria, which need a constant flow of air. To do this, a pipe is mounted above the chamber, which rises 50 cm above the ground level. Aerobic bacteria are added to a filter mounted on a pipe leading from the third section to the fourth. In fact, this is the filtration field – only in miniature and concentrated. Due to the small area of water movement and the high concentration of microorganisms, the water is thoroughly purified up to 90 – 95%. Such water can be safely used for technical needs – watering a garden, washing a car and much more. To do this, a pipe is diverted from their fourth section, leading either to a tank for storing purified water, or to a drainage ditch or well, where it will simply be absorbed into the ground..
Sewerage system in a private house – scheme of work:
Output. A septic tank with a biofilter is a good solution for a private home with permanent residence. Microorganisms can be added to a septic tank by simply pouring them down the toilet. There are no restrictions on the use of such a treatment plant. The indisputable advantage is that it does not require electricity supply. The only drawback is that sewerage wiring in a private house requires permanent residence, since without the constant arrival of wastewater, bacteria die. When new strains are added, they begin to be active only after two weeks..
An accelerated cleaning station where natural processes occur artificially. The construction of a sewage system in a private house using an aeration tank will require supplying electricity to a septic tank to connect an air pump and an air distributor.
Such a septic tank consists of three chambers or separate containers connected to each other. Water enters the first chamber through the sewer pipes, where it settles, and solid waste precipitates. Partially clarified water from the first chamber is pumped into the second.
The second chamber is actually an aeration tank, here water is mixed with activated sludge, which consists of microorganisms and plants. All microorganisms and bacteria of activated sludge are aerobic. It is for their full-fledged life that forced aeration is needed..
The water mixed with sludge enters the third chamber – a settling tank for deeper purification. Then the sludge is pumped back into the aeration tank with a special pump..
Forced air supply provides a fairly quick wastewater treatment, which can then be used for technical needs.
Output. An aeration tank is an expensive pleasure, but a necessary pleasure in some cases. The price starts at $ 3700. There are no restrictions on the installation of such a sewage system. Disadvantages – the need for electricity and permanent residence, otherwise the activated sludge bacteria will die.
Certain restrictions apply to the location of sewage facilities.
Septic tank should be located:
- no closer than 5 m from a residential building;
- no closer than 20 – 50 m from a water source (well, well, reservoir);
- no closer than 10 m from the vegetable garden.
House must be remote:
- 8 m from filter wells;
- 25 m from filter fields;
- 50 m from aeration treatment plants;
- 300 m from drain wells or stations.
The pipes leading to the septic tank must be insulated so that they do not freeze in winter. To do this, they are wrapped with heat-insulating material and inserted into asbestos-cement pipes. External sewerage wiring in a private house is carried out with pipes with a diameter of 100 – 110 mm, the slope should be 2 cm by 2 m, i.e. 2 °, in practice they do a little more – 5 – 7 ° (with a margin). But you shouldn’t joke with this matter, since a greater slope will lead to the fact that water will quickly pass through the pipes, and feces will linger and clog them, and a smaller angle of inclination will not ensure the movement of wastewater through the pipes at all. It is advisable to lay the pipes so that there are no turns and corners. For internal wiring of sewer pipes, a diameter of 50 mm is sufficient. If the house has more than one floor, and baths, sinks, and a toilet are also installed on the upper floors, then a riser with a diameter of 200 mm is used to drain the wastewater down.
If you decide that the sewerage system of a private house with your own hands is within your reach, be sure to take into account all the restrictions of SanPin and SNiP concerning the location and design of the sewerage system. In order not to spoil relations with neighbors, consider the location of their water sources and other buildings.
A private house sewerage project is extremely important; you should not try to do without it. Sewerage is not a system that tolerates approximation. Contact design bureaus or architects, let the professionals create a working project for you, taking into account all the features of the soil, site, climate and operating conditions. It is better if this project will be completed together with the project of the house itself before the start of its construction. This will greatly facilitate installation..
If you are interested in the question of how to make a sewage system in a private house with a high level of groundwater, then based on all of the above, these may be the following options:
- Sealed container for waste accumulation.
- Septic tank with biofilter.
- Aeration treatment station (aeration tank).
Directly work on the installation of a sewer system in a private house is not so difficult. It is necessary to spread pipes around the house that will collect wastewater from different sources, connect them to a collector and run through the foundation or under it along the ground to the septic tank. Excavation work can be done independently, or you can hire an excavator. But choosing the right sewage system and drawing up a project is much more important.