When discharging wastewater in a country house, it is mandatory to clean it. Since the issue of ecology remains relevant, it should be remembered that the discharge of untreated water into the soil is prohibited. In this regard, in addition to treatment systems, underground filtration facilities in country houses should be provided.
Septic tanks are used to treat domestic waste water, after which a filtration well is installed. Such measures are prescribed in the current sanitary standards. After reviewing them, you will be able to understand that the presence of underground filtration fields, sand and gravel filters and filter trenches is also important. The choice of this or that structure will depend on:
- groundwater depths;
- soil type;
- availability of aquifers and other factors.
For biological wastewater treatment today, filtration wells are still most often used.
Description
A filtering well is a structure inthe main purpose of which is the biological treatment of domestic waste water in the local sewerage system. Such treatment facilities are arranged when it is not possible to divert sewage into a reservoir through a drainage system. In such cases, the house is removed from the reservoir or the site has an insufficient slope. In this regard, there is a need to drain sewage into the ground.
The filtration well is an independent drainage facility or a sewage treatment facility. In the first case, the well is located on the site if the volume of wastewater is not more than one cubic meter per day. The second case involves the use of a well for additional purification of sewage before it is discharged into the soil.
Features of filter wells
Filtering wells are used for wastewater treatment when water consumption per day does not exceed 50 cm3. This indicates that no more than 3 people should live in the house. If we are talking about sandy loam, then the norm of the well area for such soil is 1.5 m2. As for sandy soils, this parameter is 1 m2. When the water consumption does not exceed 1 m3, then one well can be installed for 5 people, its dimensions should be equal to 2 m2 for sandy loam and 1, 5 m2 - for sandy soil.
Where to place the well
Before you build a filtration well, you need to collect information about the soil. Wells can belocated only in those soils that are suitable for this. These should include:
- sandy soils;
- peat;
- Sandy loam with low content of clay particles.
If we are talking about loams and clays, which have a low filtration coefficient, then it is pointless to install wells in them, because filtration facilities cannot be operated efficiently under such conditions. It is unacceptable to install wells for biological treatment in fractured rocks, this is due to the fact that water filtration does not occur.
In the absence of an organized runoff, water can even get into sources of drinking water. In areas with soil that has little filtration properties, other sewage treatment methods should be used.
The condition of the soil also affects the filtration area of the well. The filtration area, among other things, determines the life of the well: the filter well can last longer if the filtration area is significant. A filtration well for a septic tank can be effectively operated only if all work is carried out correctly, taking into account the depth of groundwater. This level should be 0.5 m below the filter bottom.
The base of the drainage system should be located 1 m above the groundwater level. If the groundwater is quite high on the site, then it is impossible to install a well. It is also important to remember about the depth of freezing. Do-it-yourself filtration well is installed below the freezing levelsoil, depending on climatic conditions. For example, in central Russia, this parameter is 1.3 m from the earth's surface.
Making a plastic well
If it was not possible to purchase a plastic filtration well, then you can make it yourself. For this, a corrugated pipe of the required diameter is used, the last of which can be equal to 925 mm. The required length is cut from the pipe, which will become the height of the well. Holes are made in the structure, and rubber cuffs can be used at the place where the pipes pass.
If necessary, the seams are sealed with bituminous mastic. After installing such a well, preparation is laid on the bottom, pipes are connected, and, if necessary, also a pump. The voids between the walls and the well can be filled with rubble, a hatch is installed on top.
Installation of a local bottom well
If you are thinking about how to install a filtration well, you can take a closer look at the local bottom structure, the main elements of which are:
- walls;
- overlap;
- bottom filter.
The latter has the appearance of a backfill of crushed stone, sintered slag, gravel, and brick fragments. The diameter of the fraction of these materials can vary from 10 to 70 mm. This filling is carried out to a height of 1 m. The liquid cleared of suspended particles will enter the well through a pipe fromseptic tank. Therefore, the pipe must be positioned above the filter surface. This distance is usually 0.2 m. The place where the jet will fall on the filter should be covered with an antiseptic shield, which will distribute sewage in the well. This measure eliminates backfill erosion.
Walls of the well
Quite often, owners of suburban real estate are wondering how to properly install a filtration well. Its walls can be made from:
- old barrel;
- reinforced concrete rings;
- rubble stone;
- solid clay brick.
Special attention must be paid to the fact that there should be holes in the walls. They should be left or broken. They should be distributed along the height of the filter as evenly as possible. They are performed in a checkerboard pattern, and their diameter can vary from 4 to 6 cm. The area of the holes should not exceed 10% of the wall surface. The walls of the well from the outside must be covered with the material that was used to lay the bottom filter. The height of the backfill should be equal to the height of the filter, while the thickness is usually equal to the limit of 30 to 50 cm.
Ventilation and overlap
The filter well and septic tank must be provided with a ventilation pipe. It is located in the sewage treatment plant. The upper part of the pipe is located 70 cm above the soil surface. It is important to supply the elementwind vane.
The most optimal pipe diameter is 10 cm. If it spoils the landscape, then you can solve the problem by masking the element with climbing plants. A hatch should be installed in the ceiling, the diameter of which is 70 cm. Two covers act as its features. One of them will be the carrier, while the second will be weighting, it must be placed from below. A gap should be left between the covers, which is filled with insulating material, such as bags of perlite sand or mineral wool.
Specialist recommendations
Today, filter wells rarely have a diameter of more than 2 m. Their depth is usually 3 m or less. If the area of the treatment plant is large, then several small wells should be installed on the territory. This need arises when the well area is more than 4 m2, because the volume of wastewater can be impressive. It is important to remove them from the available source of drinking water by 30 m or more.
Regulations and rules of the device
A slate filtration well can also be done independently. To do this, the sheets can be connected using a solution, holes are pre-made in the canvases, their parameters were described above. A layer of granular loading should be laid at the bottom of the structure, through which water will pass. The walls of the well can be lined with square bricks or natural stone. It is important to leave technological gaps or drill holes in the finished product.
Features of conical wells
Conical filtration well enjoys todayvery popular with consumers. It is made of plastic and can have a height of up to 2.5 m. The cone structure allows such systems to be installed in different soils, including heaving clays. The upper part of the structure has a diameter of 600 mm, while the bottom one reaches 1000 mm.
The system is supplied with a cast-iron or polymer-sand manhole, a floor slab is not required in this case. The body is based on a corrugated pipe, and the pipes are connected locally. The neck is attached to the body of the well at the manufacturing stage. The top cover will look great on walkways and lawns. A perforated conical filtration well can have a double-walled structure and an open top. The wall of the well is hollow while the bottom is open, and for the top you can use any standard manhole you want. Such a well can be installed to service a house for 10 people. The advantages of such structures should be highlighted:
- light weight compared to reinforced concrete structures;
- no toxic emissions into the soil;
- long service life up to 50 years.
The well is quite easy to install yourself.
Conclusion
In order for the cleaning facility in the form of a filtration well to cope with the tasks assigned to it, it should be located in the area where the groundwater is below the level where the filtering bottom is located from the crushed stone pillow. Distance to the bottom from the water of the treatment facilityshould be 0.5 m. The base of the well should rise 1 m above the groundwater surface.
If groundwater is quite high on the territory, then it is recommended to abandon the construction of a filter well. It is important to locate the sewer elements of the system even below the level of soil freezing. If we are talking about central Russia, then this value is equal to the limit from 1.3 to 1.4 m.
When constructing the described structures, it is especially important to follow the recommendations and technology, because otherwise the structure will not function correctly. This will cause an ecological disaster. Drinking water source may be contaminated.
