What to make a filtration well from. Filter well: example of self-design

By technical standards Filter wells can only be installed on soils with a high moisture absorption capacity. For example, on sandstones, sandy loams, peat bogs. Clay and loam make moisture filtration impossible - the wells will overflow, like ordinary storage tanks.

It is prohibited to install a well on rocks that have cracks - contaminated liquid will easily penetrate into drinking water.

• 3 square meters– sandstones;
• 1.5 square meters – sandy loam.

Minimum permissible distance to plumbing systems, mounted from, is 1.5 meters. From wells with drinking water any sewer nodes should be separated by a distance of 30-50 meters.

Special attention is given to the level groundwater. The structure must have sufficient depth, but at the same time rise one meter above the groundwater level. If in a particular area groundwater comes to the surface, it is better to abandon the filter well altogether.

Filter wells are indispensable for drainage and sewer system, because they perform an important function - they cleanse wastewater

Filter well – important element drainage or sewer system. Its main purpose is to purify contaminated water passing through it, which must be filtered before it goes into the ground or into open sources. The well retains debris and dirt, thereby purifying the liquid. There are two main types of such wells, let's talk about the features of each of them.

Home distinctive feature All types of filter wells lack a bottom. Instead, a bottom filter is installed, consisting of a so-called filter bedding. This could be crushed stone or gravel, broken brick or any other similar material. Overall height The filter layer is about one meter. Such a well requires periodic cleaning and replacement of the filter filling.

Another feature of such wells is that they can be used very limitedly and not on all types of soil. Filter structures can only be installed on sandy loam and sandy soils. On loams, and especially clay soils, their use is prohibited. This is due to the absorption capacity of soils. If a square meter of sand can absorb about 80 liters of water per day, then the same amount of clay is only five. It becomes clear that water purified from impurities in clay soil there will simply be nowhere to go. Therefore, before installing a filter well, you need to accurately determine the type of soil on the site.

Another limitation in the use of such structures concerns the level groundwater. According to the rules, it must be at least one and a half meters below the bottom of the filter layer. Considering that the well is usually located at a depth of about 2-2.5 m, it cannot be used in areas where groundwater comes close to the surface.

There are also restrictions on the amount of wastewater discharged into the reservoir per day. If their total volume exceeds one cubic meter, you must select cleaning system another type. Filter wells of any type can be installed no closer than 30 meters from residential buildings. In addition, if groundwater is used for economic purposes or for drinking, it is necessary to coordinate the location of the well with the sanitary and epidemiological inspection.

Absorption well

Such filter systems are installed in drainages and storm drains. Rain or groundwater flows to them at a slight slope through pipes. In absorption wells they are purified and sent into the ground. The main purpose of an absorption well is to remove sand and silt, as well as to drain excess water from the building and site. Therefore, the depth of such a well is small - a maximum of two meters.

The diameter of the structure usually does not exceed one and a half meters. In some cases, it is permitted to install common wells to collect wastewater in the drainage and storm systems. In this case, there are several filter wells large sizes. The structure is installed at the lowest point of land ownership so that the liquid moves to it by gravity.

Sewage filter structure

In sewerage systems, filter wells are used for additional purification of liquid entering them from treatment facilities. This can be either an anaerobic type septic tank or a hermetically sealed container in which biological purification of contaminated liquid occurs. In both cases, the wastewater remains inside the tank for three or four days, during which it undergoes oxidation under the influence anaerobic bacteria. After this, they are discharged into a filtration well, where aerobic microorganisms complete the purification. The liquid entering the soil from the filtration well is almost completely cleared of organic matter and harmful microflora.

The removal of wastewater from the house is organized in two ways. In the first case, the so-called gray drains from the kitchen, bathroom and washing machine are directly discharged to the filter structure, and fecal waste is sent to cesspool.

In the second case, they all move together into a two- or three-chamber septic tank, where sequential cleaning is carried out, after which they are sent to a filter well. Based on the method of disposal and the amount of wastewater, the number of filter structures is calculated. On average, from two to four wells can be installed for one septic tank. At the same time, you need to know that the minimum volume of such a septic tank according to the standards cannot be less than three times the daily water consumption.

To determine the number of wells, the load per square meter of its area is calculated. In this case, the type of soil must be taken into account. For sandy loam soils this figure cannot be more than 40 liters, for sandy soils - 80 liters. If the depth of the well exceeds 2 m, it is allowed to increase the load, but not more than 20%. You can also increase the load for wells located in areas with temporary residence, for example, in dachas.

Filtration structures can be very different. They are made independently from used tires, bricks or concrete rings. On sale you can find special plastic and polymer-sand containers for wells. They attract with ease of installation and durability. Regardless of the manufacturing method, filter wells are indispensable for drainage and sewerage systems, since they perform an important function - they purify wastewater, thereby preventing pollution environment. published

An autonomous sewage disposal system is an indispensable part of the infrastructure of the garden plot of any private house. The methods of its construction can be completely different: from connecting to public utility networks, to creating your own innovative wastewater treatment system. An intermediate position between these two extreme options is occupied by a filter well.

What's happened ?

Unfortunately, most residents of private houses in our country are not aware of the existence modern systems autonomous cleaning sewer drains. The experience of building an ordinary cesspool, which is a container buried in the ground, is passed on from generation to generation.

And it’s good that it’s a container, because it could very well be an ordinary pit without sealing the walls. But with the slightest mistake in choosing the location of the cesspool, with unplanned movements of the soil or a sharp rise in the groundwater level, sewage from the classic cesspool immediately ends up in unplanned places.

It’s okay if this place is just the surface of a personal plot. It is much worse if the sewage is within reach of the water intake system. This can lead to big environmental problems.

But an ordinary cesspool can be modernized so that it begins to play the role of a treatment facility, albeit not very effective, but still. We are talking about filter wells, which advantageously combine the low cost of construction (slightly more than classic cesspools) and sufficient effective system wastewater treatment (slightly less than septic tanks entry level).

How does a filter well work?

Let’s say right away that a filter well can guarantee you the purification of no more than one cubic meter of sewage per day. However, such equipment is quite easily scalable - just build a few more filter wells at some distance from each other and the volume of wastewater they purify will increase significantly.

In addition, the filter well can be used in conjunction with other water treatment facilities. For example, it can be placed as additional equipment When installing septic tanks, partially treated sewage from septic tanks will undergo additional treatment in a filter well. After passing through the septic tank and filter well sewer drain will be so clean that it can be freely discharged directly into the ground.

By the way! The name “well” indicated in the description of this hydraulic structure is quite arbitrary. Drainage and absorption trenches, a filtration field located underground and other similar structures can have the same purification effect.

Conditions for constructing a filter well

Unfortunately, a filter well cannot be built on any site. The most critical factor in the placement of filter wells is the groundwater level and the presence of an aquifer near the treatment structure. In any case, the level of the aquifer should be located no higher than the bottom of the filter well, no closer than a meter from it.

In addition, the composition of the soil on your site has a certain influence on the choice of where to build a filter well. It would be most optimal to place the filter well on sandy soils and sandy loams; peat also has excellent filtering functions. But if your site has a deep layer of clay soil, it makes no sense to place a filter well on it.

Before designing a filter well, pay attention to the area of ​​its bottom, which also differs depending on the composition of the soil on the site. So the filtering sand bed can be at least three square meters, and on sandy loams such a bed can be one and a half square meters.

When creating a filter well in sandy soils, to prevent the walls from collapsing, they can be lined with brick or stone.

Another factor influencing the construction of a filter well is the depth of soil freezing in your area. For efficient work well in winter, it is necessary that its bottom, even in the harshest winters, is guaranteed to be below the soil freezing line. For Russian regions located in middle lane, this value is approximately one and a half meters.

Basic design of a filter well

Most the best option The design of the filter well will be located after one settling chamber. This scheme is perhaps the most reasonable from the point of view of the price-quality ratio.

With this method of device autonomous sewerage wastewater through a single pipe is first sent to concrete well with a bottom that is a sump. In the settling tank, the wastewater is at rest and, as a result, light fractions of contaminants and gases dissolved in the water float up, and heavy fractions of contaminants settle to the bottom of the tank. Approximately in the middle of the height of the settling well, an overflow pipe is installed, which takes the settled wastewater into the filter well. Purified wastewater is directed into the ground through a filter well.

For such a system, a filter well with walls consisting of reinforced concrete rings is installed. The total depth of such a structure can reach three meters, however maximum depth should be at least a meter higher than the maximum groundwater level in your area.

As already mentioned, several filter wells can be built on the site. When designing their location, it is necessary to choose a place so that between the heads of the well shafts there are at least two diameters of the wells.

Choosing filter materials for a well

The most popular materials for creating a filter pad in drainage well are segments of peat bog, small crushed stone, fragments of bricks, coke, slag fractions and similar materials. It is necessary to pay attention that the largest fraction in the filter pad should not exceed 3 centimeters.

At permanent job activated sludge forms on the filter pad. It consists of colonies of microorganisms, which, in the course of their life activity, process organic residues into elementary chemical substances. This ensures additional cleaning of the sewage flowing into the well.

General principle The operation of the filter well looks like this:

• First, a filter pad made of crushed stone of small fractions is placed at the bottom of the well, then brick fragments and slag are placed on top of it;
• Backfilling between the walls of the pit and the walls of the well is also made with a material of similar composition;
• In addition, the layer of soil located under the bottom of the filter well also cleans the incoming sewage.

How to choose the shape and material of the filter well walls

In principle, the shape of the filter well can be any, but it is desirable that it be round - this will ensure a more uniform distribution of pollutants throughout the volume of filtered wastewater.

As for the material for making the walls, the most optimal are the following building materials: red brick, monolithic concrete or reinforced concrete structure, clay brick. One of the most popular materials is ready-made.

How to build your own filter well

Let's consider the procedure for constructing one of the most popular modifications of a filter well. Such a structure is formed from ready-made reinforced concrete rings.

Step 1

We choose a place to build a filter well. Since it will have direct contact with the ground, we place it away from water sources. Please note that over time, the thickness of the filter pad may form a large number of sediment that will have to be pumped out with a sewer truck, so provide a place for transport access.

Step 2

We dig a pit to the diameter of the finished reinforced concrete rings. It can be done mechanically using an excavator or manually. In order to dig a shaft for concrete rings manually, you must proceed as follows:

• install the first ring in place of the future well;
• start digging inside the ring, throwing the earth out;
• under the influence of its own weight, the ring will sink into the ground;
• After the first ring has sunk into the ground, a gasket with holes is installed. This could be, for example, bricks. The holes will ensure that relatively purified wastewater from the liquid layer goes into the ground;
• the second ring is installed and the digging of the pit continues.

Step 3

We place a sewer outlet pipe or an overflow pipe leaving the septic tank in the filter well. In any case, such a pipe should be approximately 10 centimeters higher than the upper surface of the filter pad.

Step 4

We place a filter pad at the bottom of the well. We produce with a similar composition backfill between the walls of the pit and the walls of the well.

By the way! Practice shows that the best option would be to place a filter element with a larger fraction in the center of the well, and smaller ones closer to the walls. The outlet of the sewer or overflow pipe must be located in the center of the well so that the incoming waste falls onto crushed stone with a coarse fraction.

Step 5

A ceiling is placed on top of the filter well. It can be produced using ready-made reinforced concrete slab or using durable wooden planks. If you want to use the filter well around the clock, then it would be reasonable to equip it with two covers, between which place a layer of thermal insulation. Mineral wool or sheets of foamed polymer can be used as a heat-insulating layer.

To ensure equipment maintenance, an inspection hatch with a cross-section of at least 70 centimeters is placed in the ceiling.

The remaining space is filled with soil also to provide thermal insulation.

In the ceiling of the filter well, it is necessary to provide for the installation of a ventilation pipe, the upper end of which should be located approximately a couple of meters above ground level. In this way, they will be removed from the well unpleasant odors. In order to make the head of the filter well more attractive appearance it can be disguised as a garden bed or under alpine slide.

As you can see, even with minimal technological skills and small set building materials you can install a filter well on your personal plot. When combined with a settling well, it can very well play the role of a full-fledged autonomous sewer system.

If you watch the video tutorial attached to the article, you will be able to familiarize yourself in more detail with the procedure for constructing filter wells.

Video - Filtration well

There are many ways to dispose of wastewater, so you usually choose the one that is financially feasible. Effective and at the same time the most popular option- use of a filter well. The design is traditionally used in areas with a small amount waste water, for example, in a country house or country house.

Why is it needed?

Its main task is to ensure the process of recycling wastewater by passing it through porous soil. The design makes it possible to display excess moisture beyond the water-saturated area.

Tip: install a filter well only in an area with porous soil.

These include sandy loam and sandy soils.

• from a residential building – 10 m;
• from a drinking source – 30 m.

Device

The design of the filter well constitutes a system that allows sewer pipe remove wastewater from the house by gravity to a septic tank or other settling chamber. From where they then also enter the filter well, after which they seep into the ground.

It consists of a shaft up to 3 m deep, which is lined with brick or reinforced concrete rings, sometimes other materials are used.

Filtration wells occupy an area depending on the type of soil. According to calculations, 1 m2 of sandy loam soil can filter about 50 liters of wastewater per day. At the same time, the sandy one can cope with 100 liters.

If you know approximately the volume of sewage water per day, you can select the area of ​​the future structure. The traditional size is 2 m x 2 m and a depth of no more than 2.5 m.

Tip: when making it yourself, try not to exceed these parameters.

If you need to increase the total area, it is better to make several filter structures. In this case, the distance between them should not be less than the sum of 2 diameters of the structures.

Don’t discount one more point – the groundwater level. There must be at least 1 m from the bottom of the device to the water horizon.

Features of filter manufacturing

Buy crushed stone, brick fragments, pieces of peat, coke, slag. Make sure that the dimensions of the filter material do not exceed 30 mm.

When wastewater enters the filter, sludge begins to form on it, which serves as a breeding ground for the proliferation of microorganisms. In the course of their life, they recycle organic matter into minerals, cleaning wastewater.

The water filtered in this way penetrates through the sandy soil into the lower horizons.

You can make a filter in the following way:

• determine the area of ​​the filter well from the calculation indicated above in the text;
• prepare the material in required quantity;
• lay down fine-grained crushed stone, lay brick waste and slag as the next layer;
• fill the gaps between the shaft and the well wall with the same materials;
• final cleaning water will occur after they pass through the sandy layer of soil.

The shape of the structure can be round or square, and also has a conical filtration well.

Typically the following materials are used for manufacturing:

• monolithic concrete;
• Red brick;
• reinforced concrete;
• prefabricated rings made of reinforced concrete.

When making a structure, do not touch its bottom, only cover the walls around the perimeter. Through it, the wastewater will seep lower into the ground and be further purified.

How to make a filter well

Below are instructions that can serve as a basis for you.

Make adjustments to it, but do not change the essence.

1. One of the most reliable structures that have proven their durability is a filter structure made of reinforced concrete rings, although their price is not the cheapest. They must be lowered onto the filter material, which must be evenly distributed in height. Place a stone at the bottom that will prevent the filter from being washed away by the falling stream of wastewater.
2. You also need to make holes along their entire height, observing a staggered pattern, with a pitch of 200 mm. Leave a distance of 50 mm between them. In wells where the walls are made of red brick, they are made using gaps in the masonry.

1. Install the pipe through which wastewater is supplied to the well at a height of 100 mm above the bottom filter with a slight slope. Its end should be directed towards the center of the shaft; under it, install a container for drainage with holes.
2. Make a filter at the bottom of the structure. The material for it will be pebbles, crushed stone, sand and peat. At the same time, pour large particles in the center, and small ones along the edges.
3. Make a roof for the well from wooden shield or reinforced concrete covers. It must have a hole with a diameter of 700 mm or more. Close it with hatches, between the covers of which put insulation - mineral wool, burlap, etc. Cover the structure with roofing felt on top and fill it with soil about half a meter thick.
4. Fill up outer part well with sandy loam or sand to the level of the inlet pipe. Its width cannot be less than 0.5 m.
5. Provide in the central part of the well, by analogy with the design of any type of septic tank, an air cavity with a lid and a ventilation pipe. Its diameter should be from 100 mm, and its height – from 1 m.

To remove wastewater from a private home, from a financial point of view, the easiest option is to dig sewer pit, but it leads to soil and groundwater pollution. Only the right decision There will be a installation of a filter well for sewage, which will be able to process contaminated water coming from a country house or country house.

Operating principle and purpose of the filtration well

The design of such a treatment facility assumes that wastewater flowing by gravity from the septic tank settles in a filtration well and, as it accumulates, passes through the drainage layer located in the bottom. After such cleaning, they enter the soil through preformation in the walls of the well.

The filter well can be used for the following purposes:

• Complete cleaning for homes with low water consumption, so there is no need to install a septic tank. An additional advantage is that the water is completely purified and can be used for watering the garden and flowers.
• Post-treatment of wastewater that leaves the septic tank after passing through the preliminary stages of wastewater treatment. Remaining contaminants are removed by a filter installed at the bottom of the filter structure.
• Ensuring local accumulation of wastewater. With such organization of filtration, they will not be able to spread throughout the entire area and pollute it.

The choice of this type of treatment facility assumes that after several years of intensive use, everything involved will need to be moved to another location. This forced measure is necessary, since the soil becomes unsuitable for cleaning dirty wastewater.

The filtering devices in question cannot be installed in rock formations - they will not be able to provide the necessary purification of water, and there is a high probability that contaminated wastewater will get into the drinking liquid. For clayey and rocky areas, alternative devices for filtering domestic wastewater are used.

Filtration well options

Conical well

Schematically, a conical filter well looks like this:

To roughly imagine the capabilities of such devices, you need to take into account that in sandy soil one treatment well is capable of passing 100 liters of wastewater through itself. If we take this quantity as a basis, we can calculate the required number of filters. In some cases, to increase the efficiency of the treatment device, wells can be connected in parallel, forming a modular system.

The upper diameter of conical filter wells is 0.6 m, and the lower diameter is 1 m, and the height can be different - 1 and 1.5 m, 2 and 2.5 m.

Cylindrical well

Where to install the filtration well?

The depth of such a treatment facility should not exceed 2.5 meters, while its total area is 2 m2. If the estimated area is larger, then several wells should be placed in the shaft. Between them, a run equal to two of their own diameters is maintained.

Its service life depends on the filtration area. She's being picked for different soil separately:

• For sandy loam, 1.5 m2 will be enough
• In sandy soil you need to allocate a space of 3 m2

Materials for a well filter and its design

• brick and its fragments;
• crushed stone;
• peat pieces;
• coke;
• slag.

Contaminated water, entering the filter layer, interacts with bottom silt, in which microorganisms settle. It is they who, in the process of their life activity, process minerals and organic substances and thereby purify wastewater, which then goes through the ground.

• At the bottom of the shaft there is fine crushed stone.
• Brick fragments and slag are laid on the crushed stone.
• The space between the shaft wall and the treatment well is filled with the same materials.

Do-it-yourself installation of a filter well for sewage (video)

• wheelbarrow;
• shovel;
• hammer;
• construction knife;
• axe;
• hacksaw for wood and metal;
• roulette

• Organization of access road. Having chosen a place for such a treatment device, you need to provide an access road to it. Over time, a lot of sludge forms at the bottom of its structure, and the filter ceases to cope with its purpose. In this case, you cannot do without the help of a sewer truck.
• Excavation of a pit. If reinforced concrete rings are used for the shaft walls, the process involves first installing the first ring. Then you need to dig up from inside the ring, throwing the earth out. The ring will gradually sink into the ground under the influence of its mass. After the first ring has descended underground to its full height, bricks are laid in which holes are provided in a checkerboard pattern. After this, the next ring is installed and digging of the pit continues.
• Pipe installation. It will carry wastewater coming out of the septic tank to the filter. It should be placed 10 cm above the bottom filter on a slope.
• Arrangement of the filter pad. For the bottom filter, the following is poured in the center: gravel, expanded clay, slag of large fractions, and its smaller particles near the walls. At a level of 15 cm from the bottom filter, a hole is made to the septic tank.
• Floor installation. It can be used as plastic cover suitable diameter or homemade wooden round ceiling. If the filtration device is used all year round, then it makes sense to provide for the installation of two covers, between which there will be a gap. In this space it will be necessary to distribute insulation in the form mineral wool or a sheet of foam. To make it convenient to check the condition if necessary, a lockable hatch should be provided inside the filtration device, the diameter of which should be at least 70 cm.

After digging and arranging the mine, it is covered with a large layer of earth. So as not to spoil landscape view plot, this place needs to be decorated in any way you like.