On at the moment a very pressing question is how to make a sewer system in a private country house, preferably done with your own hands? Groundwater is located very close to the surface throughout central Russia, with the exception of rare sandy areas and hills. Clayey, not very fertile soil, thoroughly saturated with water, promising high yields of cranberries, cloudberries and honey mushrooms.
Moreover, surface water prone to freezing. The depth of soil freezing in winter can reach 2 meters. Due to the danger of pipe ruptures, many in the private housing construction sector still use cesspools.
What is a sewer?
The sewer system in a private house must have a closed structure. The tasks of sewerage in a private house are to collect and transport waste to the collector, followed by filtration and disposal.
When questions arise about how to properly make a sewer system, the main problems arise when solving the problems of delivering waste to the collector, cleaning waste water and the removal of treated wastewater to aeration fields or to the drainage system.
How to remove excess groundwater
What danger does high groundwater pose and why is this groundwater so high in our area?
High standing water erodes foundations and spoils root systems trees, laying pipelines in water-filled soil is also a very dubious pleasure. Loams saturated with water are easily displaced, which leads to damage to laid pipes.
The soil structure on the plains includes significant deposits of horizontal layers of clay sediments, which do not allow groundwater to freely seep deep into the soil, as happens on sandy soil. The abundance of precipitation also contributes to the accumulation of water between clay layers.
How does dehumidification work?
Drainage ditches destroy clay layers and allow water to seep into the depths.
If the task of reclamation and drainage of swamps is set, complex events over a wide area. Special equipment and the ability to carry out work on several tens of hectares simultaneously are required.
This is the digging of a whole network of deep drainage ditches that force surface water to go deeper underground. Clearings are cut in forest areas, and reservoirs and channels are dug in swamps for water outflow.
The groundwater level can be reduced by digging deep pits, canals and settling ponds.
In a private house, especially with your own hands, it is almost impossible to complete such a volume of work.
How to heat shallow pipes?
If there is a danger of ground freezing, a heating electric cable is used. In this case, it is impossible to dig deep trenches for laying sewer pipes below the freezing level; they instantly fill with water. It is almost impossible to create waterproofing with your own hands that could protect the pipes; continuous concreting would be required.
Using a thermal cord
If the groundwater is too high and, when frozen, threatens to destroy pipes and sewer tanks, a heating cord is used, which can be wound around the pipes with your own hands. A heating cable in a private house is enough expensive solution both in terms of installation and, especially, in operation. Paying for pipe heating using electricity is wasteful.
On the other hand, if the alternative is to break frozen mountains of fecal matter with your own hands, it is better to pay the electric bill. Or install an autonomous wind turbine to provide electricity to the most necessary systems. When setting up basic systems in a private home, you should strive for the highest possible level of autonomy.
What functions does the thermal cord perform?
Prevents pipes and plumbing from freezing; for some systems, self-regulation of the temperature of the heating wire is possible. The cord is not afraid of moisture and can ensure uninterrupted operation for at least 3-5 years. Photos of installation diagrams and the design of winding loops for plumbing units can be found on specialized websites.
The dangers that arise when using a thermal cord are: burnout, mechanical damage, control system failures.
During power outages, the prospect of being left without sewerage is not very inspiring. A backup generator is required to power life support systems if centralized supply electricity will be interrupted.
Why are pit cesspools still popular?
How to make a sewer system in a house if using a heating cord is not advisable? To prevent pipes from freezing, it is logical to set up a system the old fashioned way that does not require the delivery of waste, that is, a device cesspool directly under the plumbing unit. This is the cheapest and easiest method available for DIY installation.
If installing a cesspool in a private house does not seem attractive to you, and the prospect of pumping out fecal matter with your own hands looks especially unpleasant, you should pay attention to ready-made autonomous waste processing systems.
What are AK systems?
There are now many devices on the market that vary in cost and cleaning levels. In most cases, DIY installation is not a problem. 
How does cleaning happen?
Despite the many “secret components” and other advertising tricks, the main element of an autonomous sewage system is a compressor that saturates fecal matter with oxygen. Theoretically, it is possible to install an autonomous sewer system yourself. It is enough to adapt a large and durable plastic container, build in a waste shredder, compressor and install a drainage pump at the outlet.
Independent arrangement of communications is a cost-effective and correct solution. Sewerage at high level groundwater 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 system so that it meets all sanitary safety requirements and lasts 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:
- Liquid level measurement. In the spring, you need to measure the water level in the well. A visual assessment is carried out by checking the filling of the tank after heavy rains or melting snow.
- 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 represents 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 level 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. Large costs at the initial stage are compensated by the simplicity and reliability of the system’s 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, you need to carefully process all joints. 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 unpleasant odor thanks 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. Multi-level system works on 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 is not difficult if you follow the correct procedure.
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:
- placement of 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 treatment 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 bed of gravel and sand, on which drainage pipes with perforation are located along an inclined line. 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.
Mine sewer septic tank It 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 sewage 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.
The close occurrence of groundwater is a factor that greatly complicates the installation of a septic tank on the territory of private country estates. Therefore, when planning the construction engineering communications dachas or houses, it is necessary to take into account the “situation” on the ground. Groundwater at a level of up to a meter is definitely a problem. A septic tank for high groundwater must be equipped according to all the rules - otherwise the operation of the structure will be a complete headache.
How to determine the groundwater level?
It is recommended to measure groundwater level in the spring, when the snow melts, or in the fall after prolonged rains. The distance between the surface of the earth and the “water surface” in the well, “fed” by groundwater, is subject to measurement. No well? You can also determine the groundwater level by drilling the soil with a garden drill in several places (for objectivity of observations). Well, the most easy method– just talk to your neighbors and find out from them how things are in the area.
A high groundwater level can become a problem when installing a septic tank - but knowing the rules for carrying out the work of many typical mistakes easy to avoid
The problem of high groundwater level is typical for almost the entire territory middle zone Russia. Ground flows can occur even at a depth of 20-30 cm.
What is the insidiousness of swampy terrain?
When installing and operating an autonomous sewer system in an area with a high groundwater level, each homeowner may encounter the following problems:
- Labor intensive installation. What sweet speeches you would not have heard from sellers different types structures, don’t believe it - installing a septic tank will take a lot of time and effort. However, having worked “at full capacity”, you can have no doubt that the sewerage system with a septic tank will serve you faithfully, perhaps even for decades.
- Floating septic tank. If the septic tank is not installed on a concrete pad and secured with belts, nylon ropes or cables, there is a high probability that groundwater flows will cause the septic tank to float. As a result, the structural integrity of not only the septic tank itself, but also the entire sewer pipeline is compromised.
- Water will constantly seep into a leaky septic tank made, for example, from concrete rings. This means that you will have to very often resort to the services of a sewer truck. Needless to say, this is quite expensive?
- Complete flooding of the septic tank. The systematic flow of liquid into the septic tank will quickly render the structure unusable.
- Sewage effluents entering the soil can become a source of groundwater pollution. What will this lead to? Very little time will pass and the water from the well will become unfit for consumption. Reservoirs adjacent to the site are at risk of blooming. An environmental disaster of a local nature will occur.
A septic tank installed in an area with a high groundwater level must be completely sealed - otherwise you risk both your health and the contents of your wallet
Basic rules for designing at high groundwater levels
The septic tank, if groundwater is close, must be completely sealed to prevent wastewater from seeping into the soil. Structures, bricks and other prefabricated elements are not capable of ensuring proper tightness - therefore, such options should disappear at the stage of theoretical reflection on the sewerage system. Ideally, it is advisable to resort to installing a septic tank industrial production. There is a wide range of these devices on the market with different volumes. It is worth knowing that the volume of the septic tank should be equal to the three-day volume of water consumption by the people living in the house.
After studying, you will be convinced that today you can easily purchase both a compact design for a small dacha, and a multi-chamber installation designed for a modern cottage.
A three-chamber factory septic tank is a plastic container divided into chambers. The first chamber is a place for settling and separating wastewater into fractions. The second and third are intended for wastewater treatment. Instead of filter wells, infiltrators are used in such structures - they ensure rapid absorption of 94-98% of purified water into the soil. The main disadvantage of infiltrators is the large area they occupy. The industrial septic tank itself is, of course, quite expensive. However, such an investment cannot be called an excess or a whim. A high-quality septic tank with high groundwater is a vital necessity.
If you have limited funds, you can build a septic tank yourself - from suitable plastic containers, for example, and construct it. The containers must be connected to each other with special pipes for the flow of waste.
If industrial solutions for one reason or another do not suit you, you can always build a septic tank with your own hands
When installing a septic tank in an area with high groundwater level, it is necessary to provide a reinforced concrete pad under the structure. By attaching the structure to such a base, you won’t have to worry about it being pushed out of the soil.
Also, a good option for installing a septic tank at high groundwater levels is to install. Due to the absence of seams, penetration of runoff into the ground will be impossible. The order of work will be as follows:
- digging a pit;
- installation of formwork;
- installation of fittings;
- pouring concrete.
It is advisable to pre-season the concrete mixture with a hydrophobic additive - this will improve the waterproofing properties of the future structure. Overflow holes must be provided in the partitions between the chambers. The inside of the finished chambers must be treated with coating waterproofing. If desired, such a septic tank can be built independently, without the involvement of specialists. It is enough to plan your work correctly and take into account all the nuances.
What other solutions to the problem are there?
If you have a small dacha that you visit two or three times a month, then the simplest and most cost-effective option for you would be to install a storage tank. It is desirable that it be made of fiberglass by machine winding. What would such a design look like in practice? Sewage from the home will gradually accumulate in a sealed container, and then be “extracted” by a sewage disposal machine. For rare visits, a storage capacity of three cubes is more than enough for a whole season.
One of the most important components of the proper use of a septic tank is its high-quality, timely, professional cleaning - therefore, the services of a sewage disposal machine should never be neglected!
As you can see, there are many ways to install a septic tank with a high groundwater level: in various ways. It is impossible to say in absentia which one will be optimal for you. It all depends on your financial capabilities, type of housing (permanent or temporary), and specific local conditions. After consulting with a competent specialist, we are confident that you will be able to make the right decision.
The use of a septic tank on suburban area– one of best solutions for disposal of sewage waste. However, to create optimal system it is necessary to take into account many parameters and features of the site. It should be remembered that when choosing a septic tank when the groundwater level is high on the site, not every option is suitable. The level of purification, the method of discharging recycled water, the ability of the soil to pass moisture far away is not a complete list of parameters that play a role great value. And yet, the main indicator that determines the efficiency of the wastewater treatment system should be considered not the productivity per day, not the percentage of treatment. The main criterion, perhaps, will be how clean the environment remains. After all, not only does it depend on this comfortable accommodation, but also the health of the owners, their guests and immediate neighbors.
Level measurement groundwater It is recommended to carry out during periods when it is highest. In spring - during the period of the most active floods associated with melting snow. In autumn, groundwater can reach its maximum level after long rains. The groundwater level is the distance from the surface of the water table to the surface of the soil. If there is a well on the site, measurements can be taken immediately without additional preparations. If there is no well, you should use a garden drill to make a hole in the soil and wait for it to fill with water. It is advisable to make several holes in different places - this will allow you to obtain the most objective measurement results.
Typical problems associated with high soil moisture and the proximity of groundwater:
The question of how to make a septic tank if groundwater is close is very common. This issue is connected, first of all, with the risks of groundwater pollution. Most septic tanks involve discharging processed materials into the ground. Even with a serious level of purification of 98-99%, the process water obtained at the outlet of the septic tank is not suitable for drinking and poses a health risk if it gets into the water supply. Waste water is used only for technical purposes - for household work, for watering trees, etc.
In the event that on-site disposal is not provided, a conventional storage septic tank with a high water level must still be installed with certain safety measures. The risk of waste from a septic tank getting into the ground or a nearby body of water can be caused by various circumstances: seasonal floods, failure of the storage tank seal, overfilling of the container, malfunction of the septic tank control elements (if any) and the sewer tract entering the septic tank.
Features of septic tank placement
Septic tanks are most often buried in the ground. This has both practical and aesthetic purposes. However, with all the obvious advantages, placing a septic tank underground also has some disadvantages. Before you start work, you should find out how to bury a septic tank if groundwater is close - even if it is an ordinary storage tank, there are risks. To eliminate them, all work must be done correctly. A leak in a septic tank, if it is located underground, is quite difficult to detect.
If placed incorrectly, for example, in a place low relative to the topography of the site, the septic tank is susceptible to flooding due to the accumulation of sedimentary or flood water around the lid.
Flooding can also be caused by rising groundwater levels.
Due to flooding, the septic tank fills up, and water mixed with sewage can flood the area. When flooding, if the septic tank is made of plastic, there is a risk of the septic tank floating up - to prevent this, a concrete slab is placed at the bottom of the hole in which the septic tank is placed, and the septic tank is attached to it.
Even when using a conventional storage tank, it is important to take into account nearby groundwater - a septic tank that does not involve waste treatment is installed in compliance with the norms and standards required by law. There is always the possibility of an emergency occurring. A septic tank in the form of a regular container involves the removal of waste when the container is filled with a sewer truck. When installing, it is necessary to ensure the possibility of free access of the car to the septic tank. It should also be taken into account that the procedure for pumping out sewage is not the cleanest process, so the location of the septic tank on your site should be chosen carefully.
The importance of water treatment depending on the type of septic tank
Septic tanks that process waste, in most cases, involve discharging the processed masses into the soil. They can be of two types - a septic tank with an overflow and a single-container septic tank.
An overflow septic tank, as a rule, consists of several wells, isolated from the ground and connected to each other. Sometimes a monolithic concrete septic tank is made with internal partitions that divide the entire container into separate compartments. The number of wells or compartments may vary, but usually there are two or three. The last reservoir in the overflow septic tank is a filter well for the septic tank - treated wastewater seeps into the soil through the bottom covered with sand and crushed stone. Disposal into the soil implies two functions at once - additional treatment and 
recycling. The level of purification in such septic tanks is most often not too high. High groundwater level, in this case, makes drainage into the ground unacceptable. However, when using a concrete septic tank with a high groundwater level, in certain conditions the solution is to use an aeration field instead of a drainage well.
The use of a waste bioreprocessing station that provides a purification level of 98-99%, for example, a topas septic tank from Vega, does not make it permissible for the water formed after processing to enter a well directly, although the criticality of getting into a nearby body of water is reduced, especially if there is running water there. This water is suitable for irrigation.
Soil characteristics taken into account in calculations
When calculating the parameters of the purchased septic tank, you should take into account the characteristics of the soil into which the septic tank will discharge processed wastewater. The omission of any factor can subsequently lead to the inoperability of the entire 
systems.
Basic soil parameters that should be taken into account when choosing a recycling system:
- Soil type.
- The ability of soil to pass water.
- Soil freezing depth.
Some types of septic tanks are initially intended for use in sandy soil. As a rule, such installations are characterized by a low level of purification and imply a relative remoteness of groundwater at the place of use. Sand provides high throughput. Also in sandy soil the likelihood of poorly processed waste does not cause siltation as quickly. Use such a septic tank for clay soil This is not possible, since clay has low throughput. Runoff can reach the surface of the terrain and flood the area. If the only one possible option- this is the drainage of water from a septic tank with clay soil, then the use additional measures inevitably.
In addition to global improvements to the entire system, you can take advantage of an inexpensive and effective solution by installing a septic tank filter at the outlet of the system, thereby reducing the risk of soil siltation. It is advisable to use such a filter both for soil with low throughput and for septic tanks that discharge wastewater using aeration fields. The filter retains particles remaining in the water, and thereby significantly reduces the intensity of soil siltation. In the case of using filter fields, the filter helps to avoid rapid clogging of drainage pipes.
If the site is characterized by large volumes of wastewater and a septic tank is used all year round, the use of the same filtration fields is limited when low temperatures. Freezing causes serious contamination environment. High soil moisture also imposes certain restrictions on the drainage of wastewater.
What to do if the drainage efficiency becomes low?
The possibility of siltation of the soil into which treated waste is disposed is inevitable. The owner’s task is only to build a high-quality system in order to delay this moment as much as possible. If water does not leave the septic tank, what should you do? effective solution problems? It is necessary to carefully analyze the operation of the entire system. The nature of the problem may be due to the period of use of the septic tank or emergency, and initially incorrect installation of the entire system. If the period of use of the septic tank is short, it is very likely that the malfunction is caused by errors made during installation.
If the septic tank has been used for more than a year, silting of the drainage is very likely.
If the filter well is clogged, it is necessary to empty the well and clean the bottom with sand and crushed stone. If the pit is full, then you need to call a sewage truck to pump out sewage. You can pump it out on your own using a special pump. In the case of filtration fields, the situation is somewhat more complicated. It may be necessary to clean the drainage pipes if the stagnation is caused by contamination. Siltation of the soil may require digging up or replacing the top layer.
The groundwater level is one of the most important aspects when equipping the site with a septic tank. A high groundwater level forces either not to discharge waste into the soil, or to ensure a very high level of purity of the discharged water. In addition to the GWL, there are many other parameters that can affect the quality of the system. Only after calculations can we confidently say whether for clay soil or sandy soil, also taking into account the throughput of the soil, the proximity of reservoirs and the depth of freezing.
However, pick up best septic tank for your site does not always mean buying the most expensive model. In cases where the volume of wastewater is small, there are few users, or the use of the wastewater system is seasonal, it is quite possible to buy a septic tank cheaply with a simple configuration. And it will be optimal solution for a specific area.
If you are confident in own strength no, you need to contact the manufacturer's specialists. For example, the craftsmen of the Unilos company install Astra 5 septic tanks on a turnkey basis, and if the installation is carried out by the manufacturer, he takes into account everything technical features systems and the likelihood of error is minimal.
If the central sewerage system is unavailable, home and country house owners install an autonomous system for wastewater treatment. A septic tank for high groundwater is constructed according to special rules, otherwise the device will quickly become unusable. If the groundwater level (GWL) in the area is less than 1 meter, carefully select the septic tank model and take measures to protect it from the harmful effects of subsoil moisture.
Problems of sewerage arrangement at high groundwater level
Installation and operation of a septic tank with high groundwater is complicated for several reasons:
- The complexity of manual excavation work. Digging a pit or backfilling while standing in water is difficult and uncomfortable.
- Difficulty in performing soil purification. It is practically impossible, since damp soil is not able to absorb water. For this reason, the construction of a filtration well or filtration fields is ineffective. To overcome this situation, the filter elements are placed above the ground, on a special platform. This technical solution requires additional costs - a drainage pump that pumps the contents of the septic tank into infiltration tunnels (cassettes). To prevent shallow cassettes from being torn apart by frost in winter, they are covered with earth: such a mound can be disguised as a flower bed.
- Ineffectiveness of a prefabricated septic tank made of concrete rings. The most popular option for local sewerage due to high humidity almost always loses its tightness. As a result, wastewater seeps into the soil, and external moisture enters the well. What to do if there is groundwater in the septic tank? The answer is obvious: you have to call a vacuum cleaner. Otherwise, liquid from an overfilled container may flow in the opposite direction through the outer pipes.
- Possibility of “floating up” of a plastic tank under the pressure of groundwater. The phenomenon, caused by the low weight of the structure, threatens to rupture the sewer pipeline. To “anchor” the container, it is mounted on a concrete base and rigidly fixed to it. If the septic tank floats up, the drains will have to be pumped out of it, dismantled and flushed, and then reinstalled.
Preventive measures at the sewer design stage and selection of the optimal model will help neutralize the disadvantages of high groundwater level treatment plant.
Requirements for the septic tank and its placement
When choosing a septic tank for a dacha or a house in an area with high groundwater, take into account the following design characteristics:
- Tightness. Since the body will be in constant contact with wet soil, even the most thorough waterproofing will eventually become unusable. Best option– one-piece plastic container. If you choose a cast concrete tank, you will have to ensure that cranes and trucks can enter and work in the area. In addition, concrete gradually begins to let water through, even if its surface is treated with hydrophobic compounds.
- Dimensions. When choosing a model by size, take into account the characteristics of nearby ground moisture. The height of the tank should not be too high: you will have to dig a deep hole under it, and it will be filled with water all the time.
- Volume. It is determined by calculating the average three-day amount of wastewater entering the sewer system. Take into account the number of residents and devices connected to the sewer: toilet, washing machine and dishwashers, shower stall, bathtub (its capacity also plays a role). A small reserve is added to the calculated volume of liquid drainage. It is important that the container is not empty, otherwise microorganisms that process waste may die due to lack of nutrition.
- Design . So that the septic tank does not float up at high groundwater levels , it is securely secured with clamps or ties. In this regard, a more convenient design is one that already has loops or eyes for fixation.
The cleaning system is installed in compliance with generally accepted sanitary standards: at a distance of at least 5 meters from a house or road, no closer than 15 meters from a well or well. There must be at least 30 meters to an open reservoir.
Installation features
When deciding how to make a septic tank if groundwater is close, sometimes developers install a regular single-chamber storage tank without burying it in the soil. This scheme allows you to save materials, reduce the complexity of installation and speed it up. But storage autonomous sewerage is justified only when servicing small dacha with a small number of residents and sanitary equipment. In other cases, the dimensions of the tank will be too large, but despite this, you will often have to call a sewage disposal truck.
The most rational option for high groundwater levels will be one of three options:
- Installation of a three-section anaerobic septic tank. In the first compartment, the wastewater is settled and divided into fractions, and in the second and third it is further purified. Thanks to infiltrators used in factory models instead of filter wells, 95% of the purified liquid is absorbed into the soil. Usually the product is sold disassembled: its components are assembled at the installation site according to the diagram provided by the manufacturer.
- Self-build sewer system with an infiltrator made of sealed plastic tanks or Eurocubes of suitable volume. The resulting compartments are connected to each other by pipes.
- Installation of an aerobic septic tank. It is a biorefinery station that supplies oxygen necessary for the activity of aerobic bacteria. To ensure natural air flow, a biofilter is installed - a plastic tank with expanded clay and a special ventilation system. There are energy-dependent filter models into which air is forcedly pumped using an air compressor for aeration.
To independently install an anaerobic wastewater treatment system in the presence of high groundwater, proceed as follows:
- Two wells are dug at a distance of 2 meters from each other. The dimensions of the pits are calculated so that there is 15 cm between the walls of the containers and the earthen slopes on each side. The bottom of the pits is leveled (the result is controlled by level), sand is filled with a layer of 30 cm, and compacted. Placed on a sand cushion reinforced concrete slab with special hinges. If the passage of lifting equipment for laying massive reinforced concrete slabs is difficult, the bottom of the wells is filled independently concrete mixture, having previously installed embedded parts for fixing the tanks.
- Using a bandage, each container is attached to concrete base(the belts pass through its top cover). The manufactured sections are connected by a pipe for water flow. A drain from the house is connected to the first tank. Without filling the wells with soil, proceed to the next stage.
- Dig a hole no more than 0.5 meters deep, with a perimeter half a meter larger than the cassette. The excavation is filled to the top with sand and compacted; concrete slabs 250 mm high are placed along its contour. The resulting container is filled with medium-fraction crushed stone (20-40 mm).
- Cassettes are placed on a crushed stone bed. They are connected to the second tank, in which a submersible drainage pump is installed (before this, electrical wiring is installed to connect the equipment). Be sure to install a float switch with a moisture-resistant cable to start the pump when the container is filled and turn it off when the minimum level is reached. It’s better to play it safe and install two pumps: the float of the backup unit is set to a higher switching level so that it will work if the main one malfunctions.
- When making a sewer system, the factory infiltration cassette can be replaced homemade device. For this purpose, take an oblong plastic container without a bottom (similar to a pipe), and make many small holes in it to allow the settled liquid to escape into the ground. The cassette is used only in conjunction with a septic tank, otherwise the holes will become clogged with untreated wastewater. A ventilation pipe is installed at the exit from the infiltration tunnel.
- Backfill. To protect the plastic from interseasonal soil heaving, wells are filled with a special composition: 5 parts sand to 1 part dry cement. Backfilling is carried out gradually, compacting and spilling water on each layer. To prevent the flexible plastic from bending, the chambers are gradually filled with water so that the liquid level constantly exceeds the level of the soil backfill.
Installation work It is more convenient to carry out in the summer, when the GWL is lowest. If the container is still filled with water, pump it out and then continue installation. It is recommended to install a ring drainage around the treatment plant. Dig a trench buried 20 cm relative to the freezing line of the soil. They make a sand cushion, lay perforated drainage pipes to drain groundwater in a geotextile shell, and fill them with sand and crushed stone.
Industrial production models
If preference is given to purchased installations, the question arises: which septic tank is the best for high groundwater? There is no definite answer here, since equipment is produced with different technical specifications and in a wide price range.
- "Tank" (manufacturer "Triton Plastic"). Universal three-chamber septic tank made of plastic. In the second section, anaerobic purification occurs, the third can serve as a biofilter.
- "Mole" (Aquamaster company). It is equipped with hull protection against floating and a compact biofilter.
- "Multplast". Multi-chamber model equipped with a drainage pump. If desired, you can install an aerator and upgrade the installation to the level of a deep cleaning station.
- "Bioton-B" (PolymerProPlus company). It consists of three sections, also includes a biofilter and a compartment in which a drainage pump can be placed.
