The high level of groundwater is a factor that is a stumbling block for many owners of suburban areas. It complicates not only the process of erecting buildings, but also the arrangement of an autonomous sewer. After all, the treated wastewater will not be able to leave the septic tank in the already moisture-saturated soil. Consider which version of a septic tank for groundwater is better to choose in order to permanently solve the problem, and how to build a treatment structure with your own hands.
A site in a swampy area makes its own adjustments when arranging a septic tank for autonomous sewage
When arranging a septic tank on a site with high groundwater, the owners face the following problems:
- The complexity of installation. Regardless of the type of treatment system chosen, it takes a lot of effort and time to install it.
- Sump rise. If the installation technology is not followed with the obligatory stage of arranging the concrete “cushion” and the tank is not properly secured with cables and belts, it is not uncommon for groundwater flows to push the septic tank out of the ground, thereby violating the integrity of the sewer structure.
- Water seepage. Such a fate befell septic tanks, in which insufficient attention was paid to waterproofing. In this case, you have to resort to the services of sewers much more often.
- Ground water pollution. Through the bottom and walls of leaky structures sewer drains seep into the soil, polluting groundwater and making it unfit for consumption.
Important! A prerequisite for the arrangement of a septic tank for groundwater is the tightness of the structure. Otherwise, you risk not only the contents of your wallet, but the health of your loved ones.
The easiest way to determine the groundwater level of an area is to ask your neighbors what the situation is in their areas.
The measurement of water in a nearby well will help to finally clarify the situation.
The groundwater level is measured during the off-season, when the snow melts or during the period after heavy rains. To do this, with the help of a garden drill, several holes are drilled in the area. The distance from the surface of the earth to the “smooth surface” of groundwater is taken into account.
Solutions to the problem
brick structures or concrete rings not able to provide the necessary tightness. Therefore, such options should be rejected at the design stage of the structure.
Industrial septic tanks
The range of storage tanks on the market for arranging autonomous sewage is quite wide, starting with compact tanks for small country houses and ending with multi-chamber installations for large modern cottages. The choice is limited only by the needs of the customer.
The easiest option for arranging a septic tank for a high level of groundwater is to install a tank industrial production
For example, a three-chamber septic tank is a container made of plastic, divided into three chambers: the first acts as a sump, the second and third carry out post-treatment of wastewater. The function of filter wells, which ensure the rapid absorption of the treated liquid into the soil, is performed by infiltrators.
Attention! When determining the required volume of the reservoir, they are guided by the fact that it must contain a three-day "dose" of water consumption by all households.
On average, the daily consumption of water for a family of three for household and hygiene needs is 600 liters. Therefore, the volume of the autonomous sewage storage tank should be 600 liters x 3 days = 1.8 cubic meters. To the obtained value, experts recommend adding another 20% in reserve.
In addition to the final tank, the sewer structure may include a filter well.
The filter well is a separately located reservoir, through the walls and bottom of which the purified liquid enters the soil
The only drawback of industrial septic tanks is their high cost. With a limited budget, many owners solve the problem by arranging a septic tank from eurocubes and plastic containers.
Plastic eurocubes
Owners summer cottages, intended for seasonal stay, solve the problem by installing storage tanks. The use of a plastic eurocube allows you to save not only on the cost of equipment, but also on its installation. Ground installation is also possible, but in this case, the storage tank will take up a lot of space on the site. Yes, and to pump out the contents, you will have to regularly resort to the services of sewers.
Three cubic euros of a cube with rare visits to a summer cottage is more than enough for one season
A septic tank, built with your own hands from Eurocubes, works on the principle of tightness. All cameras of the device, except for the final one, do not let drains out, nor ground water inside the tanks. As the sealed tank is filled, it is pumped out, involving special equipment for this.
Monolithic concrete structures
If industrial solutions to the problem do not suit you for a number of reasons, you can resort to the option of arranging a monolithic reinforced concrete structure. It includes three compartments. The first is a sealed tank in which solid waste and light suspensions are mechanically separated. From it, the liquid enters the second sealed container, where it is released from organic compounds by anaerobic fermentation. Getting into the third section, the liquid is finally filtered and clarified. At the final stage, a submersible pump comes into operation, which raises the treated effluents into the infiltration tunnel. From it, the liquid is discharged into the soil.
The absence of seams in the concrete structure guarantees the tightness of the autonomous sewer
The main difference between such a septic tank and the traditional version treatment plant- infiltration tunnels. They are placed directly above the groundwater level, and thanks to the laws of physics, the purified liquid is simply "pulled out" from the well into the "underground".
The diameter of such tunnels is only 150 mm, due to which they can be safely placed in the construction of sewers, even if there is a high occurrence of groundwater. But when arranging shallow infiltration tunnels to prevent freezing and ensure the smooth operation of the structure, it is important to provide for the thermal insulation of the structure. To do this, a small earthen mound is poured over the underground structure.
The slide simultaneously performs two tasks: it acts as a heater and hides the tunnel from prying eyes. To make the mound more presentable, it is often decorated as a rockery or rock garden.
Technology for arranging a treatment facility
For the construction of a septic tank, the following materials and tools will be required:
- concrete grade B15 and above;
- crushed stone and river sand;
- superplasticizer;
- reinforcing bars D 10 mm;
- infiltration element;
- sheets of slate or corrugated board;
- pipes with a diameter of 100-150 mm;
- film for waterproofing;
- boards for the construction of formwork;
- metal corners for overlapping;
- container for mixing the solution.
The volume of materials for cement mortar is calculated based on the fact that 400 kg of cement, 600 kg of sand, 1200 kg of crushed stone and 200 liters of water will be required per 1 cubic meter of the finished mixture. To increase the waterproofing properties of concrete, it is desirable to supplement the solution with a hydrophobic additive.
The connection of infiltration tunnels with a septic tank is carried out by means of a submersible pump. The float mechanism included in the package, which reacts to the liquid level, as the well is empty and filled, will turn off and start the pump.
Digging a pit
Having decided on the dimensions of the sewer wells, they begin earthworks. Digging a pit can be done manually or using small-scale mechanization.
Tip: to simplify your task, it is better to choose a dry period for construction, when the groundwater level is not so high.
Pulling out the pit to the required depth, leveling and cleaning the walls
You can make one big pit, inside which everything will fit sewer wells, or dig two separate holes, placing them at a distance of 2 meters from each other.
Construction of the base and walls
Before proceeding with the construction of walls, the waterproofing of the pit is performed. To do this, the walls of the dug pit are covered with a dense film, placing the cuts of the material so that its edges protrude 20-30 cm above the sides of the pit.
When erecting a concrete septic tank, the thickness of the walls of the tanks should be 20 cm, and the thickness of the inner walls between the chambers should be 15 cm
The construction of a reinforced concrete septic tank is carried out in the following sequence:
- The bottom of the pit is covered with sand, forming a layer 30 cm thick.
- A mesh is laid out from the reinforcing bars, the size of the sections of which is 20x20 cm.
- The reinforced bottom is poured with concrete so that the solution covers the mesh by 3-5 cm.
- After 15-20 days, when the concrete acquires the necessary strength, they begin to reinforce the walls.
- From edged boards collect "sliding" formwork. The solution is poured in layers, each time forming a wall 40-50 cm high. When the cement hardens, the formwork is shifted higher and the procedure is repeated.
- When the upper level of the walls hardens, the formwork is removed and the walls are inspected. In case of detection small cracks they need to be sealed.
- Depending on the number of tanks, one or two partitions are constructed. They are erected by arranging double-sided formwork, followed by filling the cavities with cement mortar.
- Cover arrangement. Metal corners are laid out on the walls of the structure, on top of which a plank floor is laid. When laying boards, be sure to leave a hole for mounting an inspection hatch and ventilation pipes. The future slab is reinforced with metal rods and poured with mortar.
Attention! When building a two-chamber septic tank, the size of the first tank should be 75% of the total volume. When constructing a three-chamber model, the tanks are divided so that the first chamber occupies half of the total volume, and the second and third compartments - 25%.
If you plan to install a ready-made branded septic tank, you need to take care of fixing the tank. To do this, the bottom of the pit is concreted, constructing a monolithic pillow to fix the structure.
The tank is fixed to the concrete screed by means of a cable and straps.
Concrete screed will not only act as a support for fixing the tank, but also minimize the risk of subsidence of the soil under the weight of the filled cube.
Construction assembly
When installing a septic tank from sealed containers, holes for pipes are made in the walls of the cubes. The height of the holes is determined based on the fact that the effluents freed from heavy particles from the first section through the connecting pipe enter the second chamber. The hole for the pipe in the first chamber is placed at a height of half a meter from the bottom of the tank, in the second - at a level of 15-20 cm. A pump with a float switch is installed in the third compartment, which acts as a filter block.
Important! The inner walls of the overflow holes installed between the chambers must be treated with coating waterproofing.
Both chambers are equipped with ventilation pipes, the upper ends of which rise above the ground at a height of 1.5-2 meters
The ventilation pipe in the first chamber should be 10-15 cm higher than the connecting pipe. This solution makes it possible to use the ventilation hole not only to remove harmful fumes, but also to pump out sewage with special equipment. In the second chamber, the ventilation pipe is deepened so that its lower edge is located 10-15 cm above the drainage pipes.
Having assembled the structure and checked the connecting elements, it remains only to finally fix the container. To protect the cubes from soil pressure on them, the walls of the tanks are lined with sheets of slate or corrugated board from the outside. The voids between the walls of the pit are filled with earth and rammed.
Important! Please note that plastic is sensitive to low temperatures. When operating a septic tank in a cold, harsh climate, it is necessary to provide thermal insulation.
Construction of an infiltration tunnel
The construction of the infiltration tunnel is under way. For its arrangement, next to the wells, they additionally dig a pit half a meter deep. Having laid an infiltration cassette in it, the structure is sprinkled with gravel and sand.
The infiltration cassette is an elongated plastic container, the walls of which have the smallest holes.
Through the holes in the walls of the infiltrated tunnel, the liquid seeps into the soil
Tip: if the groundwater is located very close to the surface, the bottom of the pit must first be lined with a layer of sand, then a crushed stone “cushion” 20-30 cm thick should be built, and only after that the infiltration cassette should be laid. Such a three-layer structure can only be covered with earth, having built a small mound.
Recommendations for a septic tank for high groundwater
When arranging a treatment plant, it is necessary to ensure natural movement Wastewater by pipeline. To do this, the height of the overflow and the slope of the pipeline towards the final chamber must be maintained. As an option: the second tank is installed 25-40 cm below the first.
To connect the septic tank to the infiltration compartment, a submersible pump is installed in the last compartment. To connect the pump, it is necessary to think over the mechanism for attaching the device in advance and provide for the laying of electrical wiring.
In case of unforeseen situations in which there is a high probability of overflowing the well, experienced owners recommend installing not one pump, but two. At the same time, the floats of the devices are set at different levels so that if the first pump fails, the second one automatically starts.
Video: how septic tanks and VOCs behave in high groundwater conditions
With strict observance of the installation technology, you will receive a septic tank that will serve properly for decades, even in areas with moisture-saturated soils. Expert advice will help you avoid mistakes.
When soil waters lie at a depth of about a meter from the surface of the earth, this does not allow the placement of ordinary treatment facilities, but septic tanks are required for high groundwater. To determine the depth of occurrence, it is enough to check the site with a garden drill. It is desirable to do this in 3-4 places. After that, you will need to select the appropriate cleaning system.
When groundwater comes close to the surface, and sometimes its occurrence can be located even at a distance of 30 cm or less, many homeowners have no idea how to properly install treatment equipment on the site and what it should be like.
Design installation features:
- The septic tank must be mounted on a completely flat surface;
- It is considered mandatory to install the system on a concrete pad and securely fix it with cables, ropes or belts, otherwise it may float and be damaged;
- The body of the equipment must be firmly sealed, especially for devices made of concrete rings - this way water seepage can be avoided;
- Also, poor tightness of the installation can lead to the sinking of the model and contamination of soil water with waste sewage pipes.
Measurement of the high groundwater level should be done after spring floods or in autumn, when the rains end.
IN middle lane the problem of GWL applies to many territories and areas of the suburban sector, so you will need to choose high-quality equipment for cleaning sewers.
How to choose a country sewerage with a high level of groundwater
Of course, you can use makeshift gadgets from concrete, brick and other materials, but this approach is unlikely to ensure complete tightness of the structure.
This further threatens to cause serious problems associated with poisoning of groundwater with waste and flooding of the equipment case.
It is better to choose the optimal modification corresponding to the position. Special septic tanks are well adapted to the swampy area, designed to work with GWL.
You can solve this issue in the following way:
- For a summer residence or a private house, you can choose a small model of industrial production, the rating of such modifications is very high.
- You can design your own modification from eurocubes - special containers with a plastic container inside.
- Country sewerage in a territory with a high GWL necessarily provides for the installation of a heavy concrete pillow with iron elements for a septic tank. It is even better to make a concrete well without seams, which will provide protection against sewage from entering the ground.
The well will require digging a pit, installing formwork, reinforcement and pouring concrete.
Stages of construction: how to make a septic tank if groundwater is close
High groundwater level is not an obstacle for construction sewer system.
With the independent construction of a treatment structure, the most important is:
- Absolute tightness of the case;
- For the strength and weight of the structure, it will be necessary to make a reinforced concrete pillow at the base;
- The freezing point of the soil must be taken into account.
Chambers for filtration and storage are made of metal or plastic cubes, concrete rings.
Work order:
- The location is determined - the sewer should be located 5 meters from the housing;
- A pit is being dug, the walls of which are reinforced with any wood material;
- A layer of waterproofing is placed at the bottom and a concrete solution is poured;
- After drying, another layer of waterproofing is laid, on which a septic tank is placed, while groundwater should be pumped out;
- Next going ventilation tube required to remove methane;
- The structure must be buried;
- The cover of the equipment equipped with ventilation is erected.
The design will be reliable with maximum stability. This point needs special attention.
Advantages of a concrete septic tank with a high level of groundwater
Pat UGV often forces us to look for optimally acceptable solutions for the construction of an autonomous sewage system in a private house. Unlike materials for the body of a septic installation, such as metal, plastic, reinforced concrete rings, cast-in-place concrete is more practical, since it allows you to build equipment of any size.
The main advantages of a concrete well are:
- The material is not subject to corrosion, rotting, calmly tolerates critical temperatures, is not afraid of small animals and insects;
- The seamless design is perfectly sealed and does not allow contaminants to penetrate into the groundwater;
- A concrete septic tank is the best because it is heavy, its ascent is excluded.
Concrete is the most cheap material, in this regard, the construction will not require large financial investments, which is also important.
Septic tanks for high groundwater (video)
In the countryside, especially if there is no central sewage system, the presence of aeration septic tanks is simply necessary. If a summer cottage or the territory of a private house is located in a swamp, this is not a reason to be upset. Homemade concrete septic tank or high-quality factory wastewater treatment equipment will help ensure the normal operation of an autonomous sewer system, and cleanliness, order and comfort will reign in the house for a long time.
The optimal season for determining the level of groundwater is spring or autumn. The snow melts in spring, and the longest torrential rains come in autumn.
Determine the level of groundwater
In order to independently calculate how deep the underground water arteries flow, you must use the following inventory:
- garden drill at least 200 cm long;
- a long and strong rod (if you can choose, a wood rod is better);
- spoon drill with a length of at least 500 cm.
Note. Sometimes, in order to make the most accurate calculations, 2 or more wells may be needed. At the very least, it will be easier to track the approximate level of water lying under the ground.
You can start drilling the well. The water layer closest to the surface is located no deeper than 4-4.5 m. Precipitation and melt water serve to form this layer. It is partially or completely absent in areas with increased levels of drought or prolonged frost.
Due to their proximity to the surface, these waters cannot be called the cleanest. They contain a huge amount of impurities that penetrate the soil along with rainfall. Impurities include not only various kinds of pollution, but also bacteria, which, after entering the human body, can cause gastrointestinal disorders, diarrhea, and so on. Therefore, such waters are used exclusively for irrigation.
But groundwater is located much lower: on average, at least 8-9 m from the soil surface. Therefore, the further the site is located from a natural source of water, the deeper you have to drill.
After the wells are drilled, they are left for at least 24 hours. This is necessary in order for liquid to enter the well, after a lapse of time the level of which is measured using a wood rod. You can use iron or aluminum, but this is not very convenient, because:
- First, because when wet, iron does not change color, as happens with a wooden rod;
- Secondly, iron is, in principle, heavier than wood, and therefore, depending on the initial length of the rod, it will be extremely difficult to manipulate it.
In order to calculate the approximate location of groundwater from the surface, you can use the signs of our ancestors. For example, if lingonberries with blackberries went into dense growth, it means that an underground water artery flows near the surface - no deeper than 70-80 cm. While for a cherry, apricot or cherry plum tree, an average depth of 150-160 cm will be optimal.
How septic tanks work
There are a number of models of septic tanks for a private house, which differ depending on certain modifications.
Accumulative septic tanks: the principle of operation
Accumulative septic tanks are divided into:
- concrete;
- metal;
- polyethylene;
- made from fiberglass.
Such systems are convenient for location in small areas where the runoff volume of underground flows does not exceed the “below average” bar. The septic tank collects waste water and is pumped out using a sewage truck. On average, the number of pumpings does not exceed 3-4 times a year. But depending on the relief and certain geographical features, the number of requests for sewage services may increase or decrease by the nth number of times.
If the ground flow is strong enough, then using a septic tank with a sufficiently low weight (polyethylene or made of fiberglass) is not recommended. The reason is simple - such devices will simply be pushed out of the soil over time, even weighting agents laid on top of the accumulative apparatus will not be able to hold.
However, if high level groundwater with a low flow force, it is better to use a polyethylene septic tank. This choice of a septic tank will solve a lot of problems with its transportation and subsequent installation, unlike concrete or metal. These two options, including a high water level concrete septic tank, although quite heavy, are able to withstand the strong flows of groundwater arteries.
Note. Polyethylene septic tanks are the most hermetic and can live a significantly longer operating life, unlike summer cottages made of concrete or metal.
Given the strict law on sanitary standards for the arrangement of cesspools, there can be no better alternative than storage septic tanks for summer cottages with a high level of groundwater. Thus, in a site where groundwater is high enough to the surface of the earth, a storage septic tank with a high level of groundwater will be the best solution.
Septic tanks with mandatory filter fields
Such models with filtration of sewage for a high level of groundwater are especially relevant for summer cottages. It is they who carry out water purification and are a key link in the sewerage system. The filtration field is a layered structure of sand cushion, crushed stone and irrigation pipes. In addition, it is easy to do it yourself even for a reinforced concrete structure made of rings.
The area of the filtering field is easy to determine, it is enough to know the following indicators:
- the exact area of the land plot where it is planned to install a septic tank for a summer residence with a high level of ground flows;
- how much water is filtered daily, weekly, quarterly and annually;
- in what seasons do large volume flows of liquid arrive;
- in what seasons do the minimum volumes of fluid flow enter;
- which septic tank in terms of capacity: the volume of the tank (rings or plastic - for each system, the tank parameter is required).
DIY filter field
How to make a septic tank if groundwater is close? Due to the large volume of work, special equipment will be required to set up a filtering field, because manually digging trenches of the order of 20-25 meters and a depth of at least 1 meter is almost impossible.
- It is necessary to determine the place for future installation. The minimum distance that must be retreated from any structures and natural wells is about 14-16 meters;
- Based on the area of the site and the area on which it will be possible to turn around, the area under the filtration field is calculated, the minimum area of which should not be less than 15 square meters. For a more accurate calculation, it is recommended to contact specialists;
- Next, you need to dig trenches. A prerequisite for the compliance of average indicators:
- depth not less than 1 meter;
- the width of each strip is at least half a meter.
Important! If a depth of less than 1 meter is taken, then it will be necessary to increase the cost of insulating the filter field in the winter.
- The first layer is a sand cushion, at least 30 cm thick;
- The next layer, which fills the trench, is made of gravel, also at least 30 cm thick. The thicker the filtration layer, the cleaner the water will flow;
- A pipe is laid on top of the gravel - a drain;
- The final layer is crushed stone, at least 10-15 cm;
- The whole system is covered with a geotextile film, which will help to ensure that the autonomous cleaning system does not freeze in especially severe frosts.
Note. The use of a geotextile film will also help to avoid silting, which will significantly extend the operational life of the Tank septic tank installation.
Aerobic septic tanks: which one is better
The question "Which is better to choose an aerobic cleaning system in a private house?" every second owner of suburban housing is asked, whether it is temporary or permanent housing. An aerobic septic tank for high groundwater guarantees a high percentage of cleaning - at least 98%. Such a system will ideally fit into the everyday life of home ownership, where previously there was no permanent sewage system, and you don’t want to lose the quality of life.
Of course, if you use a septic tank with high groundwater, you will have to ensure its long service life. But usually several pumpings of the septic tank are enough at a high level of flows by a sewage machine per year (depending on the number of regular users).
The septic tank device belongs to eco-friendly models. Septic tanks for summer cottages with a high level of groundwater are relevant for owners of suburban real estate, who spend most of their time outside the city and rarely use autonomous sewage with an aerobic purification method.
Disadvantages of the model:
- Most models are directly dependent on electricity, therefore, not everywhere it is possible to use such an installation;
- If the system fails, costly repairs to the installed device will be required;
- The high cost of parts (in case of failure due to power outages, it does not pay off, despite the almost 100% cleanliness of the liquid streams).
Advantages of the cleaning system:
- Installing a septic tank implies almost silent operation of the device (which cannot be said about other models);
- Deep cleaning of the soil;
- Possibility to use purified water in living conditions(98% - an indicator comparable to the level of purification of running water);
- If there are no power outages, a septic tank with a high GWL is able to work for about 5 years without any human intervention, including pumping out with a sewer;
- The system is installed in any soil, it is not pretentious, moreover, it is quite tight and durable.
TOP 6 models 2016-2017
- Official dealer in Russia ECO-DACHA (septic tank in the area with a high level of groundwater Topas);
- Manufacturer of treatment facilities Eco-Grand (a septic tank for summer cottages with a high level of soil brand "Poplar").
- Moscow manufacturer "Bioxi" - installation of a septic tank of this brand will not take long due to the lightness of the plastic construction;
- Triton-Plastic LLC is a world-famous manufacturer, the Tank septic tank is the best among autonomous stations, after which a septic tank made of concrete rings at a high groundwater level looks less effective.
- According to Internet research and user surveys, DKS-Optimum occupies a leading position among inexpensive devices with a high level of pollution removal;
- Installed septic tank for high groundwater brand Elgad for a large number users are in the best demand, unlike other analogues in this price category.
The rating was compiled according to the number of search queries, as well as according to Internet surveys of users of autonomous sewers, for summer cottages and private houses with the inability to connect to the central sewer. In most of the leading positions, models of famous brands with a small volume of the tank, as well as with additional filtration for the possibility of further use of purified water in the domestic environment.
For example, Elgad S 1400 is in great demand among summer residents with a small plot, while the energy-dependent septic tank that won the majority of votes in its category ECO-Grand 15 has a six-cubic capacity and good performance (about 2 cubic meters per day a good system can process, which is especially true for a large site with more than 7-9 regular users).
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The topic of today's publication is the use of a septic tank for summer cottages with a high level of groundwater. The successful implementation of such a project will help solve the problem of waste disposal at minimal cost.
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Creation of an autonomous sewerage system for a summer residence with a high level of groundwater
Even if you decide to entrust all the work to professionals, your own knowledge on this topic will come in handy. They will help to buy a septic tank for high groundwater without overpayments, to control the actions of the performers during installation operations. It is necessary to clarify the rules of operation in advance so as not to create unnecessary difficulties in the future. Extending the service life is very important, since a large amount of excavation, surface leveling, and landscape design are expected. Repeating such actions is associated with significant costs.
I have to choose reliable design, which is able to provide tightness for a long service life. During operation, the liquid washes out the soil, pushes the container up. Such impacts can damage the connection with the transport system. In winter, it is necessary to prevent freezing of the installation, to consider protection against heaving forces. Here are the main tasks that will have to be solved in practice. Based on this information, we will evaluate specialized equipment in general and its individual components, cleaning technologies, factory products and homemade products.
Determining the level of groundwater
Similar surveys are done in the course of creating an autonomous water supply.
A geological study is preceded by the construction of a house to clarify the depth of installation of the foundation, the calculation of the drainage system. If there is no such information, a check can be done using a conventional garden drill. They also dig pits, but this method is accompanied by significant physical exertion.
Surveys are planned for the period of spring floods, when the highest possible level of groundwater (GWL) is expected. The drilling scheme is determined in advance, taking into account the proposed installation site for the main structural elements of the septic tank itself and sewerage routes.
The purpose and principle of operation of septic tanks for cottages with a high level of groundwater
Such facilities are installed if it is impossible or too expensive to connect to the main municipal sewer. Cesspools are characterized by low productivity. These outdated cleaning products are still used in summer cottages. But for year-round operation, septic tanks are much more convenient.
The principle of operation of septic tanks for summer cottages The figure shows the main components of a modern set of equipment. Household drains through a free-flow pipeline flow by gravity into the first part of the tank. Here solid particles sink to the bottom. Immediately, the processes of biological decomposition begin. Partially treated wastewater enters the second section, where a “biofilter” with aerobic bacteria is installed to speed up the workflow. To increase efficiency, such installations are supplemented with forced air supply devices. From here, the liquid enters the infiltrator. This unit distributes waste over a large area.
For your information! With the use of such a scheme, it is possible to obtain a purification level of up to 97–98%. It is quite safe for the environment. To get this result, you need to do correct calculation and do not violate the rules for operating a septic tank for a summer residence with a high level of groundwater.
Special anaerobic bacteria are also used. They are cultivated using special techniques in an environment without oxygen. Useful decomposition processes with the use of such means occur inside the effluents. The obvious advantage is the simplification of the design due to the exclusion of the aerator, there is a reduction in energy costs. But to maintain the activity of such fillers, it is recommended to add a new portion of activators at least twice a month.
Expert opinion
Ask a specialist“In any of the options, it is necessary to create favorable conditions for the activity of beneficial microorganisms. Chlorine and other harmful compounds, antibiotics should be excluded from entering the sewer. Don't forget about ventilation holes and pipes. They are needed to remove gases that are released during the fermentation process.”
Basic rules for installing a septic tank on the site
Please note that the permitted distances to any part of the treatment plant are marked in the figure. To clarify the data, it is necessary to study the current legislation:
| Regulations | Document | Scope, features |
| Building codes and regulations (SNiP) | 2.04.03-85 | Construction of local treatment systems, transport highways for the movement of wastewater. |
| SNiP | 2.04.01-85 (2.04.4-85) | Location of sources and components of the water supply system relative to treatment facilities. |
| Sanitary rules and norms (SanPiN) | 2.1.5.980-00 | Restrictions on nature protection zones near open water bodies. |
| SanPiN | 2.2.1/2.1.1.1200-03 | The boundaries of free space near septic tanks and other objects that can harm the environment. |
The list of restrictions is too long for detailed consideration within the framework of one publication. But it should be noted that the approved rules provide for many important factors:
- filtration and throughput capacity of different types of soils;
- the effect of runoff on different types of plants;
- direction of groundwater flow.
The minimum distance from the septic tank to various types of buildings is set as follows:
- residential building - 3 m;
- workshops, garages, other outbuildings - 1m;
- buildings intended for keeping poultry, small livestock - 4 m.
The distance to the border of the neighboring site must be at least 2 m. It is imperative to take into account the distance of the marked objects in the adjacent territories.
Volume calculation and formulation of technical requirements
If guided by the provisions of SNiP 2.04.03-85, single-chamber septic tanks for summer cottages with a high water level are suitable for a runoff volume of no more than 1 m³ per day. In such a structure, new ones are constantly added to the accumulated pollution. Poorly soluble fat waste blocks the cleansing functions. Quite often you have to use the services of sewers.
A two-chamber structure is used with a volume of effluents - 1-10 m³ / day In some systems, the bottom of the second container is removed. Pebbles and other granular materials are poured there to create an additional filtration layer. But such a solution is not suitable for giving with a high level of groundwater. In the project under consideration, all septic tanks are made airtight.
With a larger amount of wastewater (> 10 m³ / day), three-chamber treatment systems are used. The capacity of the containers can be distributed in the proportion of 50%−30%−20%. But these numbers are not mandatory. The use of certain technologies is essential.
You also need to correctly calculate the required total volume. For accurate calculations, you can find a thematic calculator. The engineering formula takes into account several parameters:
- time of storage/treatment of effluents;
- typical standard for one person;
- the content of suspended impurities in the outlet pipe;
- the temperature of the incoming liquid.
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After reviewing the information provided, you can get a more complete picture of the home sewage system and the wastewater treatment system and already consciously begin to choose the design of the treatment plant.
The correct solution of everyday problems is quite acceptable using a simplified calculation. A suitable septic tank for a dacha with a high groundwater level should contain enough waste so that there is enough time for it to be effectively processed. Difficulties arise here, which are explained by the different positions of the regulatory authorities. According to building codes, the capacity of such a structure should be at least 3-day volume of sewage. The sanitary standards indicate the minimum level of pollution that is allowed to be sent for final cleaning in a natural way into the ground.
With average levels of pollution, you can use the proportion of 1.7-2.2 m³ per user. Thus, 5.5 m³ is enough for a family of three. It is better to make a margin of 10-15% to avoid insufficient treatment with an increase in the volume of effluents.
For your information! For an accurate assessment, it is necessary to take into account the volley discharge. This indicator indicates the possibility of maintaining functions during the rapid passage of the maximum number of drains.
If we are talking about storage capacity, then you will have to increase the size. The average amount of wastewater per person is 200 liters. The capacity of tanks of standard sewage equipment is from 4 to 5.5 m³. If you save too much on the initial investment, you will have to use the corresponding services more often.
When installing a compact septic tank for a dacha with a high level of groundwater with a volume of 2 m³, it will be necessary to call specialists for removal every three days Varieties of septic tanks with high GWL
Storage septic tanks at a high level of groundwater - an analogue of a cesspool
A large tank is installed underground to save space on the site The location of the structure is chosen in accordance with the considered rules. Depth is determined by the level of soil freezing. It should be higher than the main tank. A suitable neck is selected accordingly.
In this version, one camera is sufficient. To simplify control, a float sensor is installed, which signals the fullness of the container. Since a fairly frequent emptying is expected, the installation site is chosen closer to the border of the land plot, a wide and solid passage for trucks is equipped.
Expert opinion
Design Engineer VK (water supply and sewerage) LLC "ASP North-West"
Ask a specialist“Remember the standard distance to highways general use - at least 5 m.
Budget septic tanks for summer cottages without pumping
Wiring diagram for installing a septic tank for a summer residence These kits are available in different versions. The main container is divided by partitions into 2-3 functional parts. The standard package includes a cover, an inspection ladder, a ventilation system pipe, and other components. As a rule, the model range is made taking into account typical needs. It is easy to find an option suitable for a particular property.
For your information! At right choice equipment parameters, solid waste disposal will be required no more than once a year.
Biological treatment stations
What is the station made of? biological treatment After multi-stage treatment of wastewater, a good level of purification is provided. Modern stations are capable of removing up to 97-98% of all impurities, which corresponds to the best multi-chamber septic tanks for summer cottages. Such structures are ideal for areas with high groundwater levels. They are airtight, perform their functions without an additional drainage field. Regular removal of solid sediments in this case is not required. Routine flushing can be done by yourself or with the help of a service department.
Comparative analysis of different septic tanks for summer cottages with a high level of groundwater
| Type of septic tank | Advantages | Flaws |
| Cumulative | Light weight, reasonable cost, tight design. Lack of filtering fields, complex mechanisms and technologies. Ease of care. | The need for regular use of the services of sewage services. Significant loads on the road surface. |
| Multi-chamber | Long-term preservation of working capacity without calling the sewage equipment. High level of cleaning. | Possibility of environmental pollution due to incorrect installation of the filtration field. Decreased efficiency in the presence of substances, dangerous microorganisms in the effluent. |
| Biological treatment station | Compactness. Ease of installation. No additional cleaning area. | High price. Such equipment must be connected to the mains. Its complexity implies an increased likelihood of breakdowns. |
Features of materials for the manufacture of cameras
Concrete septic tank with high groundwater level
A septic tank consists of many components - basic and additional. The standard solution for our project will not work. Septic tanks for cottages with high groundwater levels are well insulated to prevent environmental pollution. To do this, close the bottom of the third tank, remove the drains from it to the drainage field.
High-quality factory-made reinforced concrete products retain their integrity for decades. They are designed for significant mechanical loads. They are not damaged by aggressive chemicals. However, it is necessary to take into account the difficulties during transportation, in the course of unloading and installation operations. To install large products, it is necessary to dig a large pit. It will take careful sealing of the joints, additional equipment with a hatch, connecting pipes.
With the use of standard reinforced concrete products, it will not be possible to optimize the volume. When the soil is heaving in winter, the displacement of the rings is not ruled out. In such a situation, soil pollution occurs. To restore the integrity of the structure and joints, a complex set of works is performed.
Plastic, combined materials
In such products, load protection is provided by metal carcass. Useful:
- tightness;
- chemical neutrality;
- light weight.
But, as in the previous example, you will have to handle standard containers of a certain volume. You will need additional equipment with a neck, a large hatch, connecting pipes. The total financial and labor costs will be quite large.
It is more profitable to buy a ready-made kit The photo shows typical features:
- flat support (1) providing good stability;
- stiffening ribs (2) to strengthen the structure while maintaining low weight;
- separate functional chambers (3) designed for sequential wastewater treatment;
- built-in pipes (4);
- mines (6) and hatches (5).
With a small weight, such a structure is pushed up with an increase in the level of groundwater. It needs to be fixed in the correct position. The disadvantages include limited strength.
Metal
Related article:
Device, principle of operation, location requirements, independent equipment treatment facilities for a private house - read in the publication.
Such a product can be made by yourself if you have the appropriate skills or by ordering in a specialized workshop. In any of the selected options, it is permissible to use the right sizes, shape, placement of internal partitions, other unique solutions. By applying a sufficiently thick sheet, it is easy to provide the necessary strength.
However, it should be noted the significant cost of a high-quality steel septic tank. The work of a skilled welder is highly valued.
A layer that protects against corrosion is required. It can be damaged during installation. Therefore, special care will be required, careful preparation of the base.
Fixing a septic tank against floating and protection against soil heaving
Algorithm of mounting operations:
- The pit is dug in accordance with the scheme provided for by the manufacturer's instructions. Observe the established slope of the walls.
- At the bottom, a sand bed of 250–350 mm is made, followed by compaction.
- Install reinforced concrete slab. From above, an additional layer of sand is made (without stones and other large fractions) with a thickness of 150–200 mm.
- Drop the septic. Install props if there are no flat supports.
- Fill the container to ½ of the nominal volume with water.
- Anchors are screwed into the reinforced concrete slab. Cables (tapes) are connected to them. Fix the septic tank in the desired position.
- Fall asleep free space in the pit in layers (200-300 mm) with a rammer. Add water at the same time.
- To prevent damage by heavy transport, a reinforced concrete slab with a hole for the hatch neck is installed on top.
When installed in clay soil, the septic tank is pushed out by heaving forces. They form where water turns to ice and then expands. To prevent damage, the container is installed at a depth below the freezing level. It is also useful to replace the original soil with sand, which allows moisture to pass through and performs damping functions.
Installation of an above-ground filtration field
If there are no natural elevations, an artificial embankment is created. To supply wastewater there, a pump is installed in the distribution well. Pumping equipment is selected taking into account the contamination of the liquid.
For your information! The location of the finishing part of the cleaning at ground level and above increases the cost of the project.
Rating of manufacturers of septic tanks for high groundwater levels
| Place | Brand | Features of the model range | Notes, positive features |
| 1. | Topas | The range includes models with cleaning performance - from 0.8 to 3 m³ or more in one day. To increase efficiency, the manufacturer offers multi-stage processing in multi-chamber septic tanks (up to 5 working volumes). | The narrow specialization of the manufacturer helped to take a leading position in the market. Experts and users note the high quality of cleaning, reliability, timely introduction of the latest specialized technologies. |
| 2. | Tank | Septic tanks under this brand are represented by the domestic enterprise Triton Plastic. Productivity of popular models: 0.6−1.8 m³/day. | Reasonable pricing policy is complemented by careful development of the smallest details. These wastewater treatment plants are well prepared for operation in difficult conditions. |
| 3. | Triton | Special Series manufacturing enterprise Triton Plastic. In the current model range there are storage tanks and multi-chamber septic tanks. | Affordable cost, wide range, ease of installation on their own. |
| 4. | Termite | Performance of popular septic tanks (m³ / day): 0.4; 0.6; 1. The range includes models specially adapted for installation in areas with a high level of groundwater. | Seamless casting technologies allow you to create strong, durable structures without defects. Each product is checked by a special set of tests before shipment to the distribution network. |
| 5. | Poplar | The manufacturer offers specialized equipment for domestic and commercial purposes. In the appropriate equipment, a large septic tank of this brand is able to clean more than 20 m³ of wastewater per day. | The equipment of this brand is distinguished by the high quality of compressors and other additional components. A higher position does not allow taking the limited technological solutions. |
Estimated prices for septic tanks for summer cottages
| Brand/Model | price, rub. | Specifications, notes |
| 79800−82300 | Productivity - 0.8 m³ / day. Volley discharge - up to 175 l. Designed for a family of four. |
| 35 800−37200 | Storage device. Volume - 3 m³. Weight −135 kg. |
| 48 500−49800 | Multi-chamber septic tank for summer cottages with a high level of groundwater. Volume - 2.4 m³. Productivity − up to 0.9 m³/day. |
| 92 400−96500 | The volume of processing per day is up to 1.9 m³. Volley discharge - 470 l. Electricity consumption - 50 W / h. |
 | 71 500−73600 | Cleaning performance − 0.5 m³/day. For a family of 2-3 people. 40W compressor included. |
For a detailed acquaintance with the parameters of the models you like, you can find the corresponding reviews on the Internet.
qwelle13, Moscow: Advantages: comfort! Fast installation, no dirt on the site! The installation of a septic tank takes place in one day. Work began at 10:00 am and ended at 4:00 pm. Turnkey works, that is, you can immediately use the toilet. The final cost includes the price of a septic tank, delivery, installation, adjustment.
Disadvantages: Maintenance is required once a year, but apparently it is indispensable.
More on Otzovik: http://otzovik.com/review_619103.html.
What is the best septic tank with a high level of groundwater
Correct conclusions can be drawn only after a careful preliminary study of the actual conditions on land plot. In addition to the groundwater level, they check the possibility of placing equipment in accordance with applicable rules and regulations. Clarify the usual and maximum needs, mode of use. Based on the collected data, a suitable model is searched for.
Use the appendix to the publication for answers to additional questions. Here you can also post your own comments on cleaning methods, features of the operation of specific septic tanks for summer cottages with a high level of groundwater.
Video (installation of wastewater treatment equipment):
If the central sewerage system is unavailable, the owners of houses and cottages install autonomous system for wastewater treatment. A septic tank for high groundwater is built according to special rules, otherwise the device will quickly become unusable. If the groundwater level (GWL) in the area is less than 1 meter, the septic tank model is carefully selected and measures are taken to protect it from the harmful effects of subsoil moisture.
Problems of arranging sewerage at high GWL
The installation and operation of a septic tank at high groundwater is complicated for several reasons:
- The complexity of manual earthworks. Digging a pit or backfilling while standing in the water is difficult and uncomfortable.
- Difficulty in soil cleanup. 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 inefficient. To get out of the situation, the filter elements are placed above the ground, on a special platform. Such a 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 flower bed.
- The inefficiency 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, runoff 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 sewer. Otherwise, liquid from an overfilled container may flow in the opposite direction through the outer pipes.
- The possibility of "floating" a plastic tank under the pressure of groundwater. The phenomenon, due to 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 pops up, it will have to be pumped out of it, dismantled and flushed, and then reinstalled.
Neutralize the disadvantages of high GWL will help preventive measures at the design stage of the sewerage, the choice of the optimal model of the treatment plant.
Requirements for a septic tank and its placement
When choosing a septic tank for a summer residence or a house on a site with high groundwater, the following design characteristics are taken into account:
- tightness. Since the hull will be in constant contact with wet ground, even the most thorough waterproofing will eventually deteriorate. The best option- one-piece plastic container. If you choose a cast concrete tank, you will have to ensure the possibility of entry and work in the area of the crane and trucks. In addition, concrete gradually begins to pass water, even if its surface is treated with hydrophobic compounds.
- Dimensions. When choosing a model in size, take into account the features of close ground moisture. The height of the tank should not be too large: 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 counting the average three-day amount of wastewater entering the sewer. The number of residents and devices connected to the sewer are taken into account: a toilet bowl, a washing machine and dishwashers, a shower stall, a bath (its capacity also plays a role). A small margin is added to the calculated volume of liquid drain. It is important that the container is not empty, otherwise the microorganisms that process waste may die due to lack of nutrition.
- Design. So that the septic tank does not float at high GWL , it is securely fixed with clamps or ties. In this regard, the design is more convenient, in which there are already loops or eyes for fixing.
The cleaning system is located, maintaining the generally accepted sanitary standards: at a distance of at least 5 meters from the house or road, at least 15 meters from the well or well. There must be at least 30 meters to open water.
Mounting Features
When deciding how to make a septic tank, if groundwater is close, sometimes developers install a conventional single-chamber storage tank without deepening it into the soil. Such a scheme allows you to save materials, reduce the complexity of installation and speed it up. But accumulative autonomous sewage is justified only during maintenance small dacha with a small number of residents and sanitary facilities. In other cases, the dimensions of the tank will turn out to be too large, but, despite this, you will often have to call a sewage truck.
The most rational with a high GWL will be one of three options:
- Installation of a three-section anaerobic septic tank. In the first compartment, the effluents are settled and divided into fractions, and in the second and third, they are further purified. Thanks to infiltrators used in factory models instead of filter wells, 95% of the purified liquid is absorbed into the soil. Typically, the product is sold unassembled: its components are assembled at the installation site according to the scheme attached by the manufacturer.
- Self-assembly of a sewer system with an infiltrator from suitable sealed plastic tanks or eurocubes. The resulting compartments are interconnected by pipes.
- Installation of an aerobic septic tank. It is a bio-purification station, which is supplied with oxygen necessary for the activity of aerobic bacteria. To ensure a natural flow of air, a biofilter is installed - a plastic tank with expanded clay and a special ventilation system. There are volatile filter models in which air is forced in, using an air compressor for aeration.
To independently install an anaerobic wastewater treatment system in the presence of high groundwater, proceed as follows:
- Dig two wells at a distance of 2 meters from each other. The dimensions of the pits are calculated so that there are 15 cm on each side between the walls of the containers and the earthen slopes. A reinforced concrete slab with special embedded loops is laid on a sand cushion. If the passage of lifting equipment for laying a massive reinforced concrete slab is difficult, the bottom of the wells is independently poured with a concrete mixture, having previously installed embedded parts to fix the tanks.
- With the help of a bandage, each container is attached to concrete base(the straps pass through it top cover). The manufactured sections are connected by a pipe for water flow. The drain from the house is brought to the first tank. Without filling the wells with earth, proceed to the next stage.
- They dig a hole no more than 0.5 meters deep, along the perimeter half a meter more than the cassette. The excavation is filled to the top with sand and rammed; concrete slabs 250 mm high are placed along its contour. The resulting container is covered with crushed stone of the middle fraction (20-40 mm).
- Cassettes are placed on a crushed stone pillow. They are connected to the second tank, in which a drainage submersible pump is installed (before that, electrical wiring is installed to connect the equipment). Be sure to install float switch with moisture-resistant cable to start the pump when the tank is full and turn it off when the minimum level is reached. It is 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 fails.
- In the manufacture of sewerage, the factory infiltration cassette can be replaced homemade device. For this purpose, they take an oblong plastic container without a bottom (similar to a pipe), make many small holes in it to let the settled liquid into the ground. The cassette is used only in conjunction with a septic tank, otherwise the holes will become clogged with untreated drains. At the outlet of the infiltration tunnel, a ventilation pipe is equipped.
- Backfilling. To protect the plastic from interseasonal heaving of the soil, the wells are covered with a special composition: 5 parts of sand to 1 part of dry cement. Backfilling is carried out gradually, compacting and spilling water on each layer. To prevent 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 is more convenient to carry out in the summer, when the GWL is the lowest. If the container is still filled with water, it is pumped out, and then the installation continues. It is recommended to equip an annular drainage around the treatment plant. They dig a trench, deepened by 20 cm in relation to the border of soil freezing. They make a sand cushion, lay perforated drainage pipes to drain groundwater in a geotextile shell, fill them with sand and gravel.
Industrial production models
If preference is given to purchased installations, the question arises: what is the best septic tank with high groundwater? There is no single answer here, since equipment is produced with different technical data, in a wide price range.
- "Tank" (producer "Triton Plastic"). Universal three-chamber septic tank made of plastic. In the second section, anaerobic treatment takes place, the third one can act as a biofilter.
- "Mole" (Aquamaster company). It is equipped with a body float protection 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.
