How to install a septic tank if groundwater is close. Septic tanks for cottages with high groundwater levels

GWL (level groundwater) determines how close to the surface groundwater comes. It’s good if it goes below the bottom of the septic tank.

But what to do if the liquid is located at a depth of only 0.5-1 m? What is the danger and how to solve the problem? A septic tank with a high groundwater level will last for many years if installed correctly.

The first thing to do is to identify the GWL and understand the scale of the problem.

Important: The liquid comes as close to the surface as possible in spring and autumn. In the first case, the cause is melting snow, in the second - prolonged rains.

Here are 5 ways to determine it:

1. The easiest way is to ask local residents. Perhaps the neighbors already know at what depth the water supply system is located or they have a well on their property.
2. Flora as a guide. Certain types of plants can only survive when water gets close enough to the surface. The following table will help you navigate:
   
3. Inspection of the site. If wetlands are present, it means that the groundwater level is located close to the surface or the soil is too clayey. And also inspect the area adjacent to the site.
4. The old-fashioned way. To do this you will need a clay pot, a tuft of wool, degreased with white spirit and the usual egg. Use a shovel to remove a small layer of turf in the area where the septic tank will be located. Place wool, an egg on top and cover with a pot. An inspection is carried out in the morning. If drops of water are clearly visible on the egg, the water level is close to the surface.
5. Drilling pits at several points in a suburban area. This method is quite labor-intensive. But it is 100% reliable. Step-by-step instruction:

• Find a good long drill - at least two meters - and a level pole, on which you apply marks every 100 mm.
• Determine drilling points on the site. You should not drill a well only in the intended location of the sump. It is possible that it will have to be moved, so select several points throughout the site.
• Drill wells. Place waterproof material on top so that precipitation cannot enter the shaft. Wait 24 hours.
• Using a prepared pole, determine the groundwater level: immerse it in the well, reaching the bottom, pull it out and subtract the length of the wet part from the depth of the shaft.

They help a lot too folk signs. This is especially true in the summer, when drilling cannot guarantee 100% accuracy of measurements. The fact is that in hot weather the liquid drains into nearby bodies of water and the level sometimes drops – quite significantly.

Places of possible flooding will help identify midges that sense the proximity of moisture and will swarm in this particular place. You can also navigate by the abundance of dew in the morning and the density of fog in the evening. The more clearly these signs appear, the closer the liquid is to the surface. Obviously, when constructing any underground structures, it is advisable to avoid such places.

A similar situation with a drop in liquid level is observed in the middle of winter. Only the reason is not in water drainage, but in the freezing of the top layer of soil during severe frosts. Measurements taken during this period can be easily misleading. With heavy rainfall, the liquid level in spring can increase 2–3 times.

Important: If possible, the groundwater level should be determined several times a year and the lowest value taken for calculations.

What problems might there be?

The installation of a septic tank with ground water level closer than two meters from the surface requires taking additional measures.

Problems that arise when installing a sedimentation tank in an area with water-cooled water supply can be divided into several groups:

1) During installation. First of all, this increases the labor intensity of the work. Digging a pit in liquid mud is not very comfortable. You will have to use a pump for pumping and organize drainage in the area. Step-by-step instruction:

• deepen the pit as much as possible in one place;
• organize drainage;
• install a vibration pump (motor pump);
• when liquid accumulates in a recess, pump it out;
• When the pump is operating, make sure that the hose does not bury itself in the ground (the pump may become clogged);
• in the meantime, develop the soil with a slope towards the excavation, which should also deepen accordingly.

After the pit has been dug, it is necessary to protect the walls from collapse. To do this, wooden or metal tongues are driven in. During the installation of the sump, water also collects in the recess and is removed using a motor pump.

Important: It’s much easier to correctly determine the level and take action in time than to deal with the consequences later.

2) Damage. As a result of excess pressure of groundwater, soil swelling occurs, and the container can be easily damaged. Sewage, mixed with underground water veins, can end up in a drinking well or come to the surface along with fecal residues. This situation can provoke infection with dangerous infections, not to mention bad smell throughout the entire area.

To avoid such sad consequences, it is enough to choose the right cleaner material. Ideally, this should be a sealed container buried in the ground. Experts recommend using modern, high-strength plastic.

But it is also important to correctly backfill the pit after installing the sump.

Backfilling is carried out special composition: you need to mix 5 parts of dry sand with 1 part of cement. Layer thickness 100–150 mm. and each one must be shed with water and thoroughly compacted.

You will have to dig out the container if the septic tank was installed incorrectly and damaged due to high groundwater, pump out the contents and find cracks. If the damage is minor, sealing can be done.

For this purpose, special sealants are used. In particular difficult cases you will need to apply a patch using a special machine for welding plastic. If significant damage occurs, the container will need to be replaced.

Important: damage to the housing can be indirectly diagnosed when unpleasant odor and siltation of the soil at the installation site.

3) The plastic sump may float. To avoid this problem, a reinforced concrete anchor-base is provided at the bottom of the pit (this can be factory-made), to which the septic tank is attached. There is no other way to cope: the container will simply float up.

In case of problems with access of lifting equipment to the work site, the slab is poured directly into the pit. Embeds are left in the concrete body, to which the tank is attached using metal clamps. Additionally, a 10 cm thick layer of sand is poured onto the bottom of the container. This design will securely hold it and prevent it from floating.

The ascent has already occurred. Step-by-step instruction:

• inspect the sump and make sure that it is not damaged - the container must be sealed;
• use a pump to pump out the contents (it is advisable to immediately call a sewer truck), if there is damage, carry out the necessary repairs;
• wash the sump;
• remove it completely from the pit;
• perform the fastening correctly (see above).

4) Flooding . Overfilling the container can be due to many reasons. And groundwater is only one of them. First of all, you should forcefully pump out all the contents, check the operation of electrical equipment, the correct connection of hoses and infiltrates.
If, nevertheless, the reason is excessive groundwater ah, especially if the level is not constant, it is necessary to organize forced pumping of the liquid. To do this, you can use another pump installed in close proximity to the outlet pipe.

If this method does not help, you will have to use a pipe to divert clean water further away, to an area with dry soil. There it can be easily absorbed into the soil, and the sump will not overflow.

To avoid such difficulties, it is better to provide a drainage system for draining groundwater in advance, even before installing the septic tank.

5) Waterlogging. With a high groundwater level, there is often a problem with final cleaning Wastewater. The soil already has high humidity. Additional moisture simply will not be absorbed. Gradually, the area around the container will turn into a swamp. To solve the problem, you need to install a filter field. Simply put, an artificial embankment, which is installed in a pre-dug pit - to the required level and is filled with crushed stone and sand 1.5-1.8 m above the ground.

The step-by-step diagram for constructing such a field is as follows:

• Conduct necessary calculations. On average, 1 person drains 200 l/day into a septic tank (established experimentally). The filtration coefficient is determined according to GOST 23278 “Soils. Methods for field tests of permeability" by pouring water into pits. Based on the tests, we determine the steady flow rate. Let's say it was 4 l/h. Pit dimensions: diameter 250 mm, depth - 100 mm. From here we determine the wetted area: bottom - 3.14 * 0.125 2 = 0.05 m 2; walls - 3.14*0.25*0.1 = 0.1 m2, S total. = 0.05+0.1 = 0.15 m2. From here, through 1 m 2 per day, 0.15/1*4*24 = 640 l/day will be filtered. Based on these data, we accept the required field area.
• Develop a pit (necessarily dry).
• A cushion is made from crushed stone 500 mm thick.
• Pour 1 m of sand.
• Lay drains ( plastic pipes with perforation). This design will ensure uniform distribution of liquid on the field. The length of the pipes should not exceed 20 m. The distance between drains is no more than 1.5 m. The supply of pre-purified water to the field is provided by a pump. When laying the pipes, they are protected with geotextiles. Each drain is equipped with a ventilation riser, which should be 0.5 m above the ground.
• Lay the filter fabric.
• Perform backfilling.

6) Drainage. Drainage of the sump can be done using a filter well.
Instead of a concrete well, you can use plastic container without a bottom, the installation of which is much simpler. Coarse sand is poured onto the bottom, then fine gravel or crushed stone. Layer thickness 200 mm. To prevent any impact on the well from the outside, it is sprinkled with expanded clay.

Requirements for a treatment device at high groundwater level

1. The body is made from durable plastic and must be airtight.
2. The structure should have a small height.
3. The volume of the tank must correspond to the daily flow rate multiplied by three.
4. Septic tanks intended for high groundwater must be securely fixed to a concrete base.

The following types of septic tanks are ideal for draining sewage during VUGV:

1. Sealed storage container. Most often, a factory-made plastic design is used. It is guaranteed not to leak and can have a volume of up to 300 liters. This system is good in a country house or in a small private house if the owners live there periodically. But it won't solve the problem permanent residence big family. The main disadvantage of this septic tank design is the regular pumping of sewage.
2. Three-section anaerobic device. The first compartment (settlement tank) serves to separate waste into fractions as a result of the separation of fats and the precipitation of solid parts. In the last two it happens pre-cleaning drains. An overflow pump supplies waste from one compartment to another. It is impossible to dispose of waste without additional filtration through the ground, as this leads to a violation of sanitary standards.
3. VOC (local treatment station). Waste passes full cycle biological treatment. With the help of bacteria, wastewater breaks down into sludge and water. Such devices are quite expensive, but the costs are worth it; if you install such a system on your site, you can forget about pumping the sewerage system for many years.

Required tools and materials

Below we will consider in more detail the process of installing a storage sump. For self-installation You will need the following tools:

• motor pump;
• shovels;
• metal cable;
• building level;
• jigsaw

You need to prepare the following materials:

• wooden or metal tongue and groove;
• boards for formwork, AIII reinforcement Ø12 mm, B12.5 concrete (with a monolithic foundation) or prefabricated reinforced concrete slab;
• clamps for attaching the container to the base;
• sealant.

DIY installation and work plan

Installation of a sump consists of the following steps:

1. Development of a pit and installation of forced drainage (the features are discussed in more detail above).
2. The pit slopes are fastened to ensure safety and protection from collapse. There should be no liquid in the pit during work. It is pumped out using a motor pump. But overnight it picks up again. This can lead to the collapse of the walls if they are not secured.
3. Installation concrete slab or concreting the base. The process is as follows:

• The bottom of the pit is leveled using a building level for control.
• Then an underlying layer of sand 150 mm thick is laid. The sand is spilled with water and thoroughly compacted.
• The next layer is waterproofing. Experts recommend using two layers of roofing felt.
• Formwork and reinforced frame are installed on the waterproofing, and concrete is poured. It must be laid in even layers, vibrating. It is advisable not to stop work for more than 4 hours. If conditions allow the passage of equipment, you can use a ready-made reinforced concrete slab, which will significantly reduce labor intensity. With a monolithic structure, you need to leave embedded parts in the concrete body to secure the tank.
• We install the finished plastic container on the prepared base, having previously calculated the required volume and checked its tightness. We use special clamps to secure the tank to the embedded parts of the “foundation” using welding or bolts. Now you don’t have to worry about it popping up.
• We connect the supply pipe, carefully seal all joints and insulate the septic tank and all pipelines.
• We carry out backfilling with protection from soil heaving as a result of a difference in groundwater level (a mixture of sand and cement with layer-by-layer spillage and compaction).

Important:

1. A layer of expanded clay with a thickness of at least 200 mm should be poured around the container. This will prevent freezing and reduce Negative influence external factors.
2. During backfilling, you need to gradually fill the container with liquid so that the water level is always above the backfilled level. This method can protect the septic tank from damage.

Operation under VUGV conditions, as well as installation, requires special measures:

1. It is forbidden to clog the system with large debris. This will cause clogging.
2. The sewer pipe and sump tank must be thoroughly insulated.
3. Drains need to be pumped out regularly. Do not allow the tank to be filled more than 2/3 full.
4. When used as a natural filter, it is worth remembering that any chemical will kill them.

Compliance with these simple rules will make exploitation sewer system easy and will relieve unnecessary problems and an unpleasant odor.

Autonomous is the only way out at high groundwater levels.

Useful video

In detail and step by step:

Installation of concrete:

In the private sector, there are often situations when there is a centralized water supply system, but there is no sewerage system. In order to use all the necessary plumbing fixtures without problems, you need to take care of drainage and wastewater treatment.

The task becomes more complicated if aquifers are located close to the surface. A solution to the problem can be a septic tank for high groundwater - the device is selected based on an assessment of the geological condition of the site and the expected intensity of operation.

Well-maintained a private house- a variety of plumbing and household appliances consuming water: toilet, kitchen sink, washbasin, bathtub or shower stall, washing machine. Dishwashers are often also installed.

As a result of all this equipment, large amounts of wastewater are generated.

Image gallery

Septic tanks are made from the most different materials– plastic, fiberglass, concrete, metal

If there is a high groundwater level in the area, serious difficulties arise: the plastic structure must be protected from floating, and the concrete structure must be carefully sealed

At high groundwater levels, instead of a filtration field, a subsoil filter cassette is constructed

Flowing through the pipes, water carries with it a lot of impurities - from sewage from the septic tank to solid particles (sand, pebbles, garbage). Her chemical composition extremely aggressive. This can cause corrosion of metal elements, damage to the integrity of pipe coatings and plumbing equipment, and mechanical damage.

All this leads to the rapid destruction of the septic tank itself and all elements of the sewer system. That is why, with a high groundwater level, you cannot save on materials and installation. The stronger and more airtight the structure, the longer the period of trouble-free operation.

Sewage is cleaned due to a large number of microorganisms. If sewage leaks into the aquifer on which wells and boreholes are built, this can result in intestinal (at best) diseases for people and diseases of domestic animals.

Groundwater moves. Even a small amount of pathogenic bacteria is enough to contaminate all drinking water sources and soil in the surrounding area. This could get real environmental disaster for terrain (+)

High groundwater is not only a risk of accidents, but also a large investment of money, especially if errors were made during installation. Depressurization will cause water to leak into the tank and it will need to be pumped out more often. Costs for sewerage services will increase sharply.

Another nuance: when designing autonomous sewerage It is necessary to immediately consider the drainage system on the site, otherwise waterlogging of the area around the septic tank is possible.

Determining the depth of groundwater at the site

The ideal option is to determine the groundwater level using hydrogeological studies. However, they rarely turn to professionals, because... it is expensive, time-consuming and difficult. You can find your way on your own, but an ordinary garden drill or folk signs will help.

Option #1: garden auger and rod

To determine the groundwater level, a drill and a rod with a length of 2 m or more are suitable. It is necessary to make marks on the rod for a tape measure. It is not necessary to mark every centimeter; marks at a distance of 5-10 cm are sufficient.

You need to make a hole the length of the drill. It happens that water comes out while drilling. This means that it is very close to the surface. However, more often you have to wait. The well is left for a day to allow water to accumulate in it.

The dry rod is lowered to the bottom of the well. Then they take it out and check to what point it is wet. All that remains is to calculate the results. For example, if the length of the drill is 2 m, and 10 cm of the rod are wet, it turns out that the water lies at a depth of 1.9 m.

The groundwater level should be measured during the period when it is highest: in early spring or in season autumn rains. This will allow you to get an objective result

Such measurements are carried out not once, but over several days, recording the results each time. If they do not change, it means that the water is located at this depth. If there is a difference, then you should focus on the lowest results. For example, if in different days If the depths are 1.9 m and 1.8 m, then the correct groundwater level is considered to be 1.8 m.

Option #2: determine by plants

Vegetation is often an indicator of the proximity of water. For example, if willow, alder, meadowsweet, and especially reeds grow on the site, then the soil is moist. You can determine the depth in meters from plants using the table below:

A good indicator may be cultivated plants– currants or sorrel. If they grow wildly without additional watering, then the water is close (+)

The slope of a maple, birch, or willow tree can indicate exactly where the water comes closest to the surface. It is best to navigate through several trees at once.

Option #3: ponds and wells

There are often small open bodies of water near the site. By the water level in them you can determine how close the aquifer is. If there are swamps, this is a sure sign of high groundwater level.

Wells dug for high water can serve as an indicator of ground water level. As a rule, such water sources are equipped for technical needs or irrigation garden plants. Drinking water get from more deep layers, because she's cleaner

Regular communication with neighbors can also help in determining the depth of groundwater, because they probably had to determine it during the construction of houses, outbuildings, hydraulic structures, and sewage systems.

Option #4: old-fashioned methods

Groundwater level can be determined using an ordinary clay pot. To do this, remove the turf from small area earth, put a tuft of defatted wool, and on top - a freshly laid egg. All this is covered with ceramic dishes and left overnight.

Old-fashioned methods help to find out that the groundwater level is high, but the exact depth can only be determined by drilling

In the morning, it is enough to inspect the wool and egg. If the wool is damp but there is no sign of condensation on the egg, the GWL is low. If the wool is wet and there are droplets of moisture on the egg, then the water obviously comes very close to the surface.

Option #5: folk signs

Routine observations can also be useful in determining groundwater level. For example, heavy morning dew and thick evening fog indicate that water is close to the ground surface. The closer the aquifer, the more obvious these signs are. They can occur even in extreme heat and drought.

Pets behave differently depending on the depth of the water. For example, cats may choose a place to rest where water is close. Dogs, on the contrary, look for the driest place on the site.

With all the disadvantages of a high groundwater level, there is also a big plus. Rodents avoid places with high humidity. This means you will be less likely to be attacked by mice. Ants behave the same way. The absence of anthills in the area may indicate high soil moisture.

Correct septic tank on an area with high groundwater level

In some cases, it makes sense to install a sealed storage tank. This is a kind of analogue cesspool. Its peculiarity is that the liquid only accumulates in the container, but is not purified.

Disadvantages: the need for frequent maintenance and high cost. On the other hand, if people do not live in the house permanently, such a sewer system will be profitable and convenient.

Storage septic tanks industrial production made from high-strength materials. The thickness of the tank walls can reach 10-40 mm. There are large volume septic tanks.

Their advantages:

• absolute tightness;
• safety for environment;
• ease of installation;
• durability.

Some models are equipped with sensors that indicate how full the container is.

You can use plastic or fiberglass containers as storage tanks or build a tank from monolithic concrete. You will have to clean them about once a month.

In most cases, the drive does not solve the problem, because... For a comfortable life, home owners need a complete sewer system. In this case, it makes sense to equip a septic tank with a bulk aeration field. The structure must be waterproof. It must be protected from floating and deformation due to soil heaving.

Features of materials for making cameras

There are a few suitable materials for arranging a septic tank with high groundwater:

• Reinforced concrete. Volume – perfect option for a house where a family of 3 or more people lives. The chambers of such a septic tank do not allow water to pass through, do not float up, and cope with the effects of aggressive chemical substances and can serve for decades.
• Plastic(containers or Eurocubes). Not the most reliable material, but it is suitable for independently installing a septic tank in the country. Pros: tightness, lightness. Disadvantages - the need to provide good protection against floating, the risk of cracks appearing when the soil heaves.
• Fiberglass. The material is highly durable, lightweight, can withstand heavy loads, and withstands chemicals well. The disadvantage is the same as that of plastic: the septic tank must be anchored during installation.

For arrangement reliable system It is best to choose reinforced concrete for sewerage. The construction of such a septic tank will be quite expensive, but you can forget about the problem of floating.

The structure will not burst if a vehicle accidentally hits it, as can happen with a plastic or fiberglass tank. It is extremely durable and repairable.

Protecting the septic tank from floating and heaving of the soil

Lungs plastic septic tanks must be recorded, because their weight is not enough to withstand groundwater pressure. They often float up. The technology of anchoring the structure itself is simple, the main thing is to strictly adhere to it.

Work order:

1. The bottom of the pit is leveled. A 30 cm thick sand cushion is poured on top and compacted thoroughly.
2. Place a base on a layer of sand– reinforced concrete slab according to the size of the structure.
3. The septic tank is mounted on a slab, secured with special belts or cables.

To protect against soil heaving, use a dry mixture of sand and cement (5: 1). After installing the septic tank, a gap remains between the structure body and the walls of the pit.

It is desirable that it be at least 15 cm. The mixture is poured into this space in layers, pouring water and compacting each layer.

Instead of a finished slab, you can use a homemade base. To do this, the bottom of the pit is filled with concrete and powerful metal loops are installed for fastenings

During backfilling, the septic tank tanks are simultaneously filled with water. Moreover, the water level must coincide with the filling level of the pit. This is necessary to equalize the loads and prevent cracks from appearing in the plastic structure.

The device of the above-ground filter cassette

If the groundwater lies deep, either or is installed for post-treatment of wastewater. In this case, the water moves by gravity, there is no need for forced pumping.

If the groundwater level is high, you need to install an additional waterproof well, pump and filter cassette. Its size is calculated based on the fact that for cleaning 0.5 cubic meters. you need a 1 x 1 m cassette.

To set up a filter cassette, 30-40 cm of soil is removed from the entire surface of the future structure, and the perimeter is fenced with concrete blocks so that their height is level with the ground.

This space is filled with crushed stone (fraction from 20 to 40 mm), and a tank without a bottom is placed on top, under which a pipe from the septic tank is connected. The structure is insulated and covered with a layer of soil 30 cm thick.

TOP 10 best septic tank manufacturers

If groundwater lies close to the surface, you can choose an industrial septic tank. It is guaranteed to be airtight, the rest depends on the quality of installation.

Topas septic tanks have only two drawbacks: high cost and energy dependence. Otherwise, they are impeccable: compact, effective, do not emit any odors.

There are several brands that have proven themselves well in the domestic market:

1. . These are plastic, non-volatile structures with body wall thicknesses of up to 17 mm. They withstand loads well and are resistant to temperature changes. The design is designed so that the tank does not float under the influence of groundwater.
2. . Septic tanks of various sizes and purposes are produced under this brand. When installing the model, you need to anchor it. If they are installed correctly, they can last up to half a century.
3. "Leopard". The manufacturer produces energy-dependent and independent models. This three-chamber septic tanks with two levels biological filtration. The structures are reliable, strong and durable.
4. . These are reliable systems for comprehensive wastewater treatment. The advantages of septic tanks include compactness, durability, and high throughput. The disadvantage is energy dependence and the need for appropriate maintenance.

If it is necessary to install a septic tank in an area with a high groundwater level, two main questions arise: what technology to use and how much will it cost? The technological aspect depends on the location of the site and the degree of influence of groundwater on the properties of the soil. The cost of a structure is influenced by its type, quantity and variety of materials used, the amount of work and many other factors.

When building a septic tank, it is necessary to take into account throughput systems and daily water consumption. These indicators significantly influence the complexity of the design, its dimensions and cost. Septic tanks for dachas, which perform their functions only in the appropriate season, will be much cheaper than permanently operating complexes operated in country houses, inhabited all year round.

Septic tanks: general information and design

A septic tank differs from a classic cesspool not only in its depth, but also in the principle of distribution of wastewater components. A settling pit is an artificial cavity with sealed walls and bottom. The wastewater that falls into the pit settles, separating into water and solid fractions that settle to the bottom. When filling the pit, liquid and sludge must be pumped out using a sewer truck.

A similar principle is implemented in a septic tank, but is only one of the stages of wastewater treatment. In general, the complex consists of:

• primary settling tank;
• one or more secondary settling tanks;
• aeration tank (optional);
• water drainage systems.

Thus, in septic tanks, multi-stage wastewater treatment is carried out with the subsequent removal of liquid into the ground, reservoir or other discharge point. The solid residue can be pumped out with a sewer machine or processed using special microorganisms. Sludge that has been processed is suitable for Agriculture as an organic fertilizer.

Installing a septic tank is a rather complex, but quite doable process. Having the appropriate tools, experience in carrying out land work, and knowing the technological aspects, you can install a septic tank on your own. During work, it is important to maintain the integrity of the system, that is, install the entire sewer complex at once.

No less important is right choice material of the main elements of an autonomous treatment system. A septic tank can be made from:

• metal;
• bricks;
• polymer material;
• concrete;
• rubber, etc.

Metal and brick septic tanks in areas with high groundwater levels are considered less relevant. To protect the structure from moisture, you will have to carry out a series of additional work on waterproofing and insulation of septic tanks. It is more rational to install a septic tank from concrete rings or install plastic containers.

A set of works for installing drainage for a septic tank in an area with high groundwater level

All septic tank systems can be divided into two types:

1. Horizontal.
2. Vertical.

In the first case, we are talking about systems that have a small depth but sufficient area. To install them, you will need a shallow but wide trench, with a durable (cushion-reinforced) bottom and walls. Also, horizontal structures need insulation, especially in cases where the system involves microorganisms that decompose organic matter. Vertical septic tanks (for example, made of concrete rings) are more compact, less sensitive to weather conditions and relatively easy to install. But, to place a well in an area with a high groundwater level, it is necessary to provide additional drainage and waterproofing.

The most effective system to reduce groundwater level and protect the septic tank from destruction and flooding is ring drainage. In this case, it is assumed that a drainage pipe will be installed underground, along the entire perimeter of the house. That is, an artificial underground cavity encircling all buildings drains excess groundwater to the discharge point, thereby preventing its accumulation. For creating drainage system perforated polymer pipes are used, laid in trenches slightly above the first waterproof layer. For effective drainage operation you will need:

• maintain a pipe slope sufficient for unhindered water flow;
• reliably protect drainage channel from clogging;
• provide protection from mechanical impact;
• think over a system of inspection, overflow and storage wells;
• use quality materials.

If the site has a certain level of slope, installing a drainage line will not be difficult. To provide normal speed For water outflow, a pipe slope of up to 15 cm/m is sufficient. When working on an area with differences in elevation, it is necessary to install overflow wells that help change the angle of inclination of the pipe. Also, storage wells equipped with electric pumps are effective. The first option is preferable due to its complete autonomy and independence from energy resources.

After placing overflow or storage wells, drains are connected to them. The pipes are placed in trenches, where a gravel bed is first laid and geotextiles are lined to protect the drain from clogging. Pipes wrapped in filtration material are covered with gravel and soil. They are connected to the wells using the tapping method, followed by insulation of the joints. Coating, penetrating or spray waterproofing can be used to seal entry and exit points. Pasting with roofing felt or other types of welded sheet material is ineffective.

Work on installing a septic tank on an area with high groundwater level

Work on installing a septic tank begins with calculations. The scope of excavation work is determined based on the size, type and configuration of the wastewater treatment system. The most important step is choosing the appropriate location to place the structure. GOSTs, SNiPs and other standards give clear recommendations and determine the distance at which the septic tank should be located relative to buildings and wells with drinking water.

We use manual and mechanized labor for the work. Job hand tools will save money, but will take much more time. In addition, shovels may not cope with rocky soil or be ineffective when digging a deep pit. Renting earthmoving equipment will increase costs, but will significantly speed up the work process.

In addition to choosing the method of carrying out the work, it is important to decide on the season when it will be carried out. The start time of work depends on the characteristics of the soil. In the event that the GWL is constantly high, it is better to carry out earthworks in winter. When there is a periodic rise in groundwater, you should wait until the rains end and the groundwater level decreases.

Installing a septic tank and drainage in a problem area in winter, preferably in any case. Solid soil that is not subject to erosion will allow you to quickly and most reliably organize a cushion and a concrete chamber for installing a septic tank. It is worth noting that a “shambo” caisson is required when placing a septic tank in an area with a high groundwater level. The septic tank installation process is carried out in the following sequence:

• Digging a pit with a drainage cushion made of gravel-sand mixture (15 cm gravel, 10 cm sand).
• Waterproofing the walls and bottom of the trench with rolled material.
• Laying reinforcing mesh.
• Filling screed with a thickness of 10 cm.
• Installation of formwork for pouring caisson walls with a thickness of 10 cm.
• Installation of a septic tank.
• Floor installation.

When working with concrete, it is important to wait for the regulated periods necessary for the material to gain grade strength. Additionally, adding additional components to the dry mixture, for example, Penetron, will allow you to protect the concrete structure from the effects of water. Holes for pipes are constructed before the concrete hardens. To do this, through couplings are installed in the soft mixture.

Groundwater can be a problem not only when building a house, when you dig a foundation pit or trench, but also when installing utility lines. Since the depth of freezing of the water supply system is middle lane In Russia it is 2 meters, you have to dig deep trenches, install them - if you are doing water supply, they are made, buried 2-3 meters - if you are doing sewerage.

It’s okay if you know in advance that there is groundwater on the site and have prepared for it, but it happens that you start digging and nothing portends trouble. During the excavation process, after 0.5-1 meters the earth begins to float, walls fall down, and water comes out of the ground.

To prevent the walls from falling, it is done wooden formwork. 50-gauge boards and timber are taken. 2-3 base skirts are made from the timber and boards are inserted between the timber and the ground; as they deepen, the boards are driven into the ground. Due to the formwork, it is more convenient for you to dig a pit, since the walls will not collapse and, most importantly, it is safer to dig this way.

Options for septic tanks for groundwater

For groundwater I know 2 types of septic tanks as a solution to the problem:

• septic tank with a low body.

Septic tanks with forced

One of the most common options for solving problems with groundwater is a septic tank with forced pumping of treated wastewater with a built-in drainage pump. In this case, a standard septic tank is buried 2 or more meters into the ground, always with formwork for safety and speeding up the process (without formwork, the pit can increase more than 2 times during the excavation process, and therefore more shoveling and a lot of time will be spent).

A forced septic tank is a sealed container with a complex internal device for processing wastewater, it has an additional chamber for purified wastewater, this chamber contains drainage pump, which releases wastewater under pressure. In this case, installation is simplified in that the water can simply be directed into a ditch or trench. There is no need to dig a well, make drainage trenches or drainage fields.

Septic tanks with low body

Manufacturers of septic tanks understand the problem of customers; they know that groundwater sometimes greatly complicates the installation process. As has already become clear from the above installation process, installing a septic tank in soil with high water levels can take a long time, and it’s not a fact that it will be possible to do it at all, there are such swampy places that while you’re digging, the same amount comes.

Manufacturers from companies such as Kolomaki and Alta Group produce septic tanks with a lower body. What does it mean. For example, a standard septic tank has a height of 2500 mm, the pit for it must be prepared to the same depth, as well as make a bedding, level it and install a septic tank. As you understand, groundwater will not allow this process to be completed efficiently.

The solution to this problem is a septic tank with a lower body. The height of the septic tanks is:

As you can see, there is no need to dig a deep pit to install a septic tank. Despite the fact that this septic tank does not cost more, as well. Prices for such septic tanks start from 90 thousand rubles.

Such a septic tank is easy to install, since it is enough to dig a pit up to 1.5 meters, prepare a cushion, and install a septic tank with a low body.

An important point is that the depth of the supply pipe here is up to 50 cm.

Advantages of a septic tank with a low body:

• not a deep pit;
• less sand for backfilling a septic tank, which means less costs for cement;
• no special equipment required.

Conclusion

As you can see, in modern world There are solutions to problems such as high groundwater. You just need to ask how to find a solution. Those who are not looking will not be able to come across this article and cope with the UGV.

Independent arrangement of communications – economical correct solution. Sewage with a high groundwater level has nuances of construction and operation. The peculiarity of a cesspool for a house such as a private one is its tightness.
Construction of a sewer system for high groundwater is quite expensive, but this way you are guaranteed to see a high-quality result. How to make a sewer so that it meets all requirements sanitary safety and served for many years? Consider the proximity of moisture to the soil.

Risks of proximity to groundwater

Groundwater is an underground aquifer that is close to the surface of the earth. The groundwater level can rise if there has been heavy rain the day before or the snow is melting. In dry weather, the amount of subsoil moisture decreases.
Increased soil water levels complicate the installation of treatment systems, wells and building foundations:

• the structure of the street toilet is destroyed.
• an unpleasant odor appears;
• the risks of intestinal infections increase;
• The service life of underground pipes is reduced - metal corrosion occurs.
• The walls of the cesspool are washed away by water, which prevents its cleansing.

There are several ways to understand how close groundwater is:

1. Liquid level measurement. In the spring, you need to measure the water level in the well. Visual assessment carried out by checking the filling of the tank after heavy rains or melting snow.
2. If there is no well, you can drill several holes with a garden drill and see if they are filled with water.

If both technologies are not available to you, contact your neighbors who use on-site wastewater treatment plants.

Construction of a cesspool

Construction of a sewer system in a private house with a high groundwater level in the form of a cesspool is undesirable. Possible flooding threatens difficulty in cleaning, rapid filling, erosion of the edges of the trench and destruction.

Storage capacity: installation features

The design is an ordinary pit, barrel or well made of concrete rings. The advantage of the structures is their low cost of construction. There are quite a lot of disadvantages:

• The container should never overfill, so choose products with a large capacity;
• at high groundwater levels, the tank must be regularly treated with sealants;
• place the structure in a place convenient for access by the sewage disposal service;
• Frequent calls for a sewer truck mean financial costs for the owners.

Storage tanks are inexpensive to build, but their operation can take a lot of time and money.

Installation of a mechanical septic tank

Country sewerage with a high groundwater level must be airtight. A mechanical septic tank is popular due to its price-quality ratio. High costs for initial stage are paid off by the simplicity and reliability of system operation.

The degree of purification of waste liquids is adjusted by adding wells.

If the soil water level is low, 1 well will be sufficient; if the soil water level is high, 2 or 3 wells will be sufficient. The choice of materials for the construction of a septic tank must be approached responsibly, since with high groundwater it is necessary to prevent flooding of communications. Wells can be plastic or concrete, but the criteria for their organization are the same:

• When installing a septic tank from ready-made concrete rings, all joints must be carefully processed. This will prevent the structure from collapsing;
• The ideal option is to cast the well on site. To do this, you will need an iron form, which you can rent;
• plastic septic tanks for correct installation will be durable and effective.

The dimensions of an autonomous sewer system for a private house must be calculated correctly. Its capacity is equal to the amount of water consumed by a family of 4 people in 3 days.

Advantages of a septic tank when groundwater is close to each other

Installing a sewer system in the form of a septic tank in a private house with a high groundwater level has many advantages:

• absence of unpleasant odor due to the tightness of the structure and ventilation.
• there is no need to call a sewer service. The waste decomposes and is discharged into the deep layers of the soil.
• there is no risk of soil contamination by waste. Waste liquids undergo thorough multi-level filtration. However, it is not recommended to install a sewer drain nearby drinking wells.

At correct operation the design will maintain durability and integrity.

Operating principle of autonomous sewage system

Autonomous country sewerage, properly constructed when the groundwater level is high, can improve the quality of life of site owners. The multi-level system works according to the following principle:

• the used liquid flows into the septic tank, where insoluble inclusions are retained.
• solid particles settle at the bottom of the container, and fats and insoluble substances form a film on the surface.
• wastewater enters the septic tank compartments, where it is purified using anaerobic bacteria.
• the organic environment that comes with wastewater promotes the growth of bacteria, which reduces the concentration of harmful substances.
• ventilation removes the gases formed during the decomposition process.

The settled and clarified liquid enters infiltration tunnels, where it is purified and discharged into the ground.

Septic tank installation algorithm

Making a sewer system in a private household will not be difficult if you follow correct order actions.

Regulatory regulation of sewerage devices

Home cleaning system requires careful adherence sanitary rules. The removal of sewage from the house, as specified in the requirements of SNiP 2.04.03-85, provides for:

• accommodation treatment facilities 50 meters from drinking wells or wells.
• sewer lines are located 3 meters from the plantings.
• The septic system is installed at a distance of 5 meters from residential buildings.
• sewage disposal equipment must have unimpeded access to the treatment plant.

Planning of cleaning networks is carried out according to a strict order - 1 inspection well per 15 m of straight or rotary sections. Work must be carried out in strict order.

Digging a pit

Conducting home sewerage for a dacha, if groundwater is close to the ground, it begins with digging a hole:

• The pit completely includes the septic structure. In this case, the tank should not touch the walls at a distance of 25 cm;
• keep the bottom as even as possible, compacting it with wet river sand. Fine-grained material is laid in a layer of about 15 cm and thoroughly compacted. The sand should not contain foreign particles in the form of lumps of earth or gravel.
• To ensure the tightness of communications, sand is replaced with a concrete slab.

The walls of the pit must be reinforced with wood formwork or metal sheets.

Installing a septic tank in a pit

The finished septic tank is checked for cracks and damage before installation.

The container is lowered to the pit using cables. It must stand perfectly level in the pit, even the slightest tilt is unacceptable. In cold winter conditions, it is recommended to wrap the tank with a layer of heat-insulating material.

Backfilling the trench

After installation, the tank is filled with soil or a cement-sand mixture and thoroughly compacted. The ground level reaches the edge of the supply pipe.

Arrangement of the infiltrator

Filtration structures must be connected to the container to purify the water before it enters the ground from the container. There are several options:

• Filtration fields with a cushion of a layer of gravel and sand, on which there are located along an inclined line drainage pipes with perforation. The length of the pipes reaches 20 meters, and the distance of the extreme points is 2 meters. The seepage is located 1 meter higher than the expected elevated aquifer.
• Water supply to a ditch is suitable for clay soils. Filtered water is removed using pumps.
• A water intake for a home, like a filter, is built when the water is planned to be used for agricultural needs, or it is not possible to build another structure. Pipes are connected to the tank from the septic tank. A sand cushion must be built around it. To protect against overflow, an outlet pipe is constructed, which, when large quantities water discharges it into an underground filtration field, a ditch, or back into the septic tank.
• A good solution for a private house with a high groundwater level is a ground filter cassette. It is constructed as follows:
  • They dig a hole 50 cm deep, which is filled to the top with sand.
  • foam blocks about 30 cm high are laid around the perimeter.
  • crushed stone is poured inside.
  • A filter cassette made of plastic and insulation is placed on top.

Your sewer septic tank will begin to function normally only after 2-3 weeks. During this period, a sludge sediment forms at the bottom of the tank, which actively participates in the waste processing process.
The quality of a sewer system made by yourself at the dacha directly depends on the quality of the containers and pipes used, as well as the correct installation.

Proper construction of a dacha sewer system at a high groundwater level will ensure filtration of waste liquids by 99%.

However, the resulting water is not edible and is exclusively technical.