Drainage is a system of underground channels, called drains, through which the removal and lowering of the level of groundwater and flood waters is carried out. Drainage is a branched system of pipes and wells that are located around or along a building or site protected from moisture. Pipes can be equipped with special filters that prevent the system from silting up and allow you to do without cleaning the drainage for a long time.

Select and design in accordance with the requirements:

• sufficient culvert capacity;
• strength when exposed to backfill soil and dynamic loads;
• resistance to aggressive groundwater;
• convenience of the device and operation of drainage.

To the greatest extent, these requirements are met by single-layer and double-layer plastic pipes made of low-pressure polyethylene (HDPE), polyvinyl chloride (PVC), as well as polypropylene (PP) and high-density polyethylene (HDPE). Depending on the material and design, they belong to different stiffness classes.

The choice of drain pipe design is determined by the application conditions and operating requirements.

The dimensions of the water inlets of the drainage pipes should be selected taking into account the granulometric composition of the drained soil. This requirement should be taken into account when choosing pipes presented on the modern construction market with various options for drainage slots.

Traditional designs are single-layer pipes with a smooth or (more often) corrugated surface, which increases the strength of the pipe, maintains its flexibility and increases the water-holding area of ​​the drainage holes. Modern designs are two-layer and even multi-layer pipes. The latter are effective at high dynamic loads and depths of the protected object.

In two-layer pipes, the inner wall is smooth, and the outer shell is corrugated, securely fastened to the inner layer. Thanks to the smooth inner wall, the speed of the water flow increases and the conductivity of the pipe increases. The presence of an external corrugated shell makes the pipe structure resistant to impact deformation, which is especially important when transporting and installing pipes in winter conditions. Such pipes are distinguished by a high water-draining and self-cleaning capacity, they usually “keep” a small predetermined slope of the drainage route well.

Drain pipe laying

Drainage pipes are laid in a trench, the bottom of which is leveled to give the pipeline a design slope in accordance with GOST 30412-96, and the construction of wells is completed, while the following conditions must be observed:

• the width of the trench along the bottom depends on the depth of the drain, the diameter of the pipeline, the width of the excavator bucket and should be at least 40 cm.
• in cross section, the trench may have a rectangular or trapezoidal shape. In the first case, the walls of the trench are strengthened with the help of inventory shields, in the second - with 1: 1 slopes.
• the device of trench drainages of all types is recommended to be carried out in the dry season. In the presence of soils of high humidity, waterlogged, as well as in the event that surface or groundwater enters the trench, it is recommended to perform drainage work in separate grips with preliminary complete or partial drainage.
• the bottom of the trench should not contain solid inclusions (hard lumps, brick, stone, etc.) that can push through the bottom wall of the pipe laid on them.
• the installation of the pipeline is carried out at the bottom of the trench, where each drainage pipe, one by one, is successively inserted into the socket of the previous one, formed by a two-socket coupling. If necessary, the pipes are cut between the corrugations with a hacksaw for wood or metal. Couplings are mounted manually; if necessary, it is possible to use scrap, winches, and an excavator bucket. Sealing rubber rings are not used when mounting couplings in drainage systems.
• at the end of the installation work, the drainage pipeline is sprinkled with so-called drainage sprinkles, which, in accordance with the composition of the drained soils, can be single-layer and multi-layer.
• to increase the durability of the drainage system, it is recommended to arrange a geotextile sheath around the drainage backfill and the drainage pipe itself.
• installation of drains from pipes is carried out at an outdoor temperature of up to minus 10 °C.

Drainages using drainage pipes should be designed in such a way as to exclude the possibility of water freezing in them and in drainage devices.

Transit drainage pipes are made without perforation and arranged without filtering sanding. In terms of design and technical characteristics, they are similar to gravity storm sewer pipes.

Before the drainage is put into operation, the horizontal drain should be thoroughly washed, and inspection wells should be freed from foreign objects and soil. Horizontal pipes are flushed with a strong stream of water supplied from a water pipe or tank truck to free the drainage pipes from the introduced soil particles.

Drain pipe depth

The permissible maximum depth of drains depends on the pipe material, the smallest depth of pipe laying is determined by the requirements for their protection from dynamic loads and freezing.

In weak soils with insufficient bearing capacity, the drainage pipe should be laid on an artificial base.

Drain pipe slope

The smallest drainage slopes are determined based on the minimum allowable water flow rate in the drainage pipes of 1.0 m/s, at which the drains do not become silted. The largest slopes are determined based on the maximum allowable water velocity in the pipe. The maximum speed determines the intensity of soil suffusion around the drainage pipe, depends on the characteristics of the geotextile filters and the filter cake. If necessary, drainage can be designed with differences of 0.3 - 0.9 m, arranged in manholes. The slope of the bottom of the drainage should be constant or increasing towards its lower part. Fractures of the longitudinal drainage profile are allowed in manholes.

Drainage sprinkles

When the drainage is located in gravelly, large and medium-sized sands with an average particle diameter of 0.3-0.4 mm and larger, single-layer gravel or crushed stone sprinkles are arranged; when located in medium-sized sands with an average particle diameter of less than 0.3-0.4 mm, as well as in fine and silty sands, sandy loams and with a layered structure of the aquifer, two-layer sprinkling is arranged - the inner layer of crushed stone sprinkling, and the outer layer - from sand. Fractions of crushed stone should be smaller than the size of the corrugation cavity. Crushed stone according to GOST 8267-93 should not contain clastic elements with sharp edges.

When using drainage pipes in a filter shell made of gravel or crushed stone, a single layer can be used.

Typical options for laying drainage pipes

• I - with a single-layer sprinkling of sandy-gravelly soil;
• II - drainage pipes in a geotextile filter sheath;
• a) in a trench with vertical walls;
• b) in a trench with slopes;
• 1 - trench contour;
• 2 - local soil;
• 3 - backfilling of the trench with uneven-grained sand;
• 4 - single-layer sprinkling with small gravel;
• 5 - drainage pipe

drainage well

concrete wells

Traditional well designs should be made of reinforced concrete rings with an internal diameter of 1000 mm, wells with pumps - 1500 mm.

The connection of plastic drainage pipes with concrete wells is carried out by fixing the pipe in the well using cement mortar. At the junction, it is possible to use substances that increase the adhesion of "plastic - concrete", for example, liquid rubber. In many cases, when constructing drains, the tightness of the joints is not required.

The hole in the well should have a diameter as close as possible to the outer diameter of the pipe. All gaps formed must be filled with cement mortar, which must meet the requirements for ensuring the density of the concrete joint.

In the process of installing the pipe in the concrete or reinforced concrete wall of the well, it is necessary to provide a rigid support for the free end of the pipe by adding soil until the concrete has completely set. The drainage pipe should not be concreted simultaneously with the construction of the walls of a monolithic well, since this can cause the pipe to deform under the weight of uncured concrete.

In traditional reinforced concrete wells, a sedimentary part with a depth of at least 0.5 m is required in the last manhole of the network at the starting section of the transit drainage, in overflow wells, as well as in manholes along the drainage route after 40-50 m.

Plastic wells

Modern compact manhole designs – made of plastic with a minimum diameter
315 mm. The latter are manufactured at the factory and delivered ready-made to the construction site or assembled on site from the appropriate elements.

Preference should be given to plastic manholes made of prefabricated elements assembled on site. It is advisable to use wells and plastic pipes of the same system, since in this case all the necessary components are available: for connecting pipes to each other, pipes and manholes, anti-freeze devices, etc. Such a drainage system is the most efficient in terms of operation and durability.

The design of a prefabricated well consists of three main parts: bottom, vertical and cover or hatch. Pipes are either cut in place into the lower part of the vertical structure, or there are factory bends in it. As a rule, the option of tapping pipes in place is preferable. The structural elements of wells are made of various materials based on the conditions of their work. The upper part - the hatch, depending on the purpose of the territory and the expected loads, is performed in various versions. The vertical part of the well can be a single-layer corrugated or two-layer pipe made of various materials (PVC, HDPE, PP), the bottom of the well is made of PP.

Wells made of plastic products are arranged with a settling part (sand trap) with a depth of at least 0.5 m and are cleaned using mechanization.

Drainage well device

For the operation of the drainage system, inspection (inspection) wells are arranged along the drainage route. Wells are installed at the sources of drains, in places where the route turns, changes in slopes, on drops, in straight sections at certain distances, as well as in places necessary for flushing drainage lines.

Distance between drainage wells

On straight sections, the distance between wells is recommended to be taken for pipes up to 150 mm - no more than 35 m, for pipes over 200 mm - no more than 50 m.

At the corners of the drainage at the ledges of buildings and at the chambers on the channels, the installation of manholes is not necessary, provided that the distance from the turn to the nearest manhole is not more than 20 m. after one turn.

Drainage water diversion

Drainage water can be drained:

• inside the storm sewer
• by gravity to the surface
• into the underlying permeable layers
• pumping from storage wells

When designing drainage systems, preference should be given to drainage systems with gravity drainage. Drainage systems with forced pumping of water require additional justification.

In all cases, it is necessary to comply with the requirements of regulatory documents for environmental protection.

Release of water into the storm sewer

Discharge of drainage water into storm sewers is allowed if the throughput of storm sewers is determined taking into account the additional costs of water coming from the drainage system. In this case, the backwater of the drainage system is not allowed.

Release of water to the surface

Water drainage to the day surface should be carried out on areas of the terrain from which it is impossible to recharge groundwater in the area of ​​the drained structure. The route of the collectors is assigned on the basis of a technical and economic comparison of options.

If there are auxiliary workings arranged for the construction period, the possibility of their use for groundwater drainage should be considered.

Water release into underlying rock layers

The discharge of drainage water into the underlying rock layers is allowed if they have sufficient absorption capacity and additional recharge of the layer will not cause negative consequences (for example, groundwater pollution, creation of groundwater backwater over time, etc.).

Release of water into a water body

The outlet of drainage water into a water body (river, canal, lake) should be located in plan at an acute angle to the direction of the flow, and its mouth part should be provided with a concrete cap or reinforced with masonry or riprap. When released into a reservoir, drainage should be laid above the water level in the reservoir during a flood.

With a short-term increase in the horizon of the reservoir, drainage, if necessary, can be laid below the flood horizon, provided that the drainage outlet is equipped with a check valve.

The wellhead section of the drainage outlet into the reservoir should be buried below the water horizon to the thickness of the ice cover with the installation of a drop well.

Drainage water pumping

Pumping of drainage water by pumps is allowed if it is impossible to ensure gravity drainage or bypass into the underlying layers. In such cases, it is necessary to provide special pumping stations with tanks, the design of which should be guided by the requirements of SNiP 2.04.03-85, and when using pumped water for water supply - SNiP 2.04.02-84.

Cleaning of drainage wells and pipes

In the process of periodic inspections (at least four times a year), inspection of the condition of manholes, drainage pipes, collectors is carried out, as well as control measurements of water flow, carried out in manholes by volumetric method.

A decrease in flow (compared to the calculated one) indicates a decrease in the throughput of drainage pipes, which may be caused by:

• sedimentation of drainage pipes in separate sections;
• damage to drainage pipes;
• overgrowth of the section of drainage pipes due to silting or clogging;
• calmation of openings of filter cuts;
• clogging of geotextile filters.

Manholes must be regularly cleaned of dirt and debris. Wells must be closed at all times during the life of the drain.

Drain cleaning is carried out in the following ways:

• high pressure water rinsing

Produced using nozzles with a diameter of ~2.8 mm, pressure up to 120 bar. With this technique, the impact effect on the blockage and the impact area is significantly increased, and the risk of pipe destruction is less. The size of the nozzle nozzle must match the characteristics of the water supply equipment. A pressure of 60 bar is sufficient to remove soft deposits. A pressure of 80 to 120 bar can remove larger solid deposits.

• cleaning ball

A spherical polyethylene, polyurethane or rubber device, smaller than the inner diameter of the sewer pipe, is pulled through the pipe.

• cleaning with a polyethylene piston

A piece of polyethylene pipe is used according to GOST 18599-2001, fixed on a cable, which is stretched inside the drainage pipe between adjacent wells to remove blockages and deposits. The outer diameter of the piston must be less than the inner diameter of the pipeline to be cleaned.

The use of metal scrapers and ruffs for cleaning drainage pipes is not allowed.

If the cleaning methods listed above do not work, the line is shifted or the filter bedding and geotextile filter are replaced.

If you ask any experienced builder, developer, landscape designer about what needs to be done, first of all, on a newly acquired and not yet built-up site, the answer will be unequivocal: the first is drainage, if there is a need for it. And this is almost always the case. The drainage of the site is always associated with a very large amount of excavation, so it is better to do them right away so that later you do not disturb the beautiful landscape that any good owners equip in their possessions.

Of course, the easiest way is to order site drainage services to specialists who will do everything quickly and correctly, using special equipment. However, this will always come at a cost. Perhaps the owners did not plan these expenses, perhaps they will violate the entire budget planned for the construction and arrangement of the site. In the proposed article, we propose to consider the question of how to do the drainage of the site with your own hands, as this will allow you to save a lot, and in most cases it is quite possible to do these works yourself.

Why is site drainage needed?

Looking through the estimates and price lists related to the drainage of the site, some developers begin to doubt the appropriateness of these activities. And the main argument is that earlier, in principle, no one "bothered" much on this. With such an argument for refusing to drain the site, it is worth noting that the quality and comfort of human life have greatly improved. After all, no one wants to live in dampness or in a house with earthen floors. No one wants to see cracks in their house, on the blind areas and paths that appeared after the next cold season. All homeowners want to improve their yard or, to put it in a modern and fashionable way, to make landscaping. After the rain, no one wants to "knead the mud" in stagnant puddles. If so, then drainage is definitely needed. You can do without it only in very rare cases. In which cases we will describe a little later.

Drainage? No, I haven't heard...

Drainage is nothing more than the removal of excess water from the surface of the site or from the depth of the soil. Why is site drainage needed?

• First of all, in order to remove excess water or from the foundations of buildings and structures. The appearance of water in the area of ​​\u200b\u200bthe base of the foundation can either provoke soil movement - the house will “float”, which is typical for clay soils, or, in combination with freezing, frost heaving forces may appear that will create efforts to “squeeze” the house out of the ground.

• Drainage is designed to remove water from basements and basements. No matter how effective waterproofing is, excess water will still seep through building structures. Basements without drainage can become damp and encourage the growth of mold and other fungi. In addition, precipitation in combination with the salts present in the soil very often form aggressive chemical compounds that adversely affect building materials.

• Drainage will prevent the "squeezing out" of the septic tank at a high level of groundwater. Without drainage, a wastewater treatment system will not last long.
• Drainage in conjunction with the system and around the buildings ensures that water is quickly removed, preventing it from seeping into the underground parts of the buildings.
• Drainage prevents waterlogging of the soil. In areas equipped with well-planned and made drainage, water will not stagnate.
• Waterlogged soil can cause rotting of the root parts of plants. Drainage prevents this and creates conditions for the growth of all garden, garden and ornamental plants.
• With heavy precipitation in areas that have a slope, the fertile soil layer can be washed out by water flows. Drainage directs water flows into the drainage system, thereby preventing soil erosion.

Water erosion of fertile soil in the absence of drainage is a serious problem in agriculture

• If the site is surrounded by a fence built on a strip foundation, then it can "seal" the natural ways of water drainage, creating conditions for waterlogging the soil. Drainage is designed to remove excess water from the perimeter of the site.
• Drainage helps to avoid the formation of puddles on playgrounds, sidewalks and garden paths.

When Drainage Is Necessary Anyway

Consider those cases when drainage is needed in any case:

• If the site is located on a flat area, then drainage is mandatory, since when a large amount of precipitation falls or snow melts, the water will simply have nowhere to go. According to the laws of physics, water always goes under the influence of gravity to a lower place, and on a flat landscape it will intensively soak the soil in a downward direction, which can lead to waterlogging. So, from a drainage point of view, it is beneficial for the site to have a slight slope.
• If the site is located in a lowland, then its drainage is definitely needed, since water will drain from higher places to those below.
• Strongly sloping sites also require drainage, as rapidly draining water will erode the top fertile soil layers. It is better to direct these flows into drainage channels or pipes. Then the main part of the water will go through them, preventing the soil layer from washing out.
• If the site is dominated by clay and heavy loamy soils, then after precipitation or snow melt, water will often stagnate on them. Such soils prevent its penetration into the deep layers. Therefore, drainage is essential.
• If the groundwater level (GWL) in the area is less than 1 meter, then drainage is indispensable.

• If the buildings on the site have a heavily buried foundation, then it is likely that its sole will be in the zone of seasonal groundwater rise. Therefore, it is necessary to plan drainage at the stage of foundation work.
• If a significant part of the area of ​​​​the site is covered with artificial coverings made of concrete, paving stones or paving slabs, and if there are lawns equipped with an automatic irrigation system, then drainage is also needed.

From this impressive list, it becomes clear that drainage to one degree or another is necessary in most cases. But before you plan and do it, you need to study the site.

Studying the site for relief, soil type and groundwater level

Each site is individual in terms of relief, soil composition and groundwater level. Even two sites located nearby can be very different from each other, although there will still be a lot in common between them. Modern construction requirements suggest that the design of a house should begin only after geological and geodetic surveys have been carried out with the preparation of special reports that contain a lot of data, most of which are understandable only to specialists. If they are “translated” into the language of ordinary citizens who do not have education in the field of geology, hydrogeology and geodesy, then they can be listed as follows:

• Topographic survey of the area where it is supposed. The photographs must show the cadastral boundaries of the site.
• A characteristic of the relief, which should indicate what type of relief is present on the site (wavy or flat). If there are slopes, then their presence and direction are indicated, it is in their direction that water will flow. Attached is a topographic plan of the site indicating the contour lines of the relief.

• Characteristics of the soil, what kind of soil it is and at what depth it lies on the site. To do this, experts drill exploratory wells in different places of the site, from where they take samples, which are then examined in the laboratory.
• Physical and chemical properties of the soil. Its ability to be load-bearing for the planned house, as well as soil in combination with water, will affect concrete, metal and other building materials.
• The presence and depth of groundwater, their seasonal fluctuations, taking into account exploration, archival and analytical data. It is also indicated in which soils water can appear and how they will affect the planned building structures.

• The degree of heaving of soils, the possibility of landslides, subsidence, flooding and swelling.

The result of all these studies should be recommendations on the design and depth of the foundation, the degree of waterproofing, insulation, protection from aggressive chemical compounds, and drainage. It happens that on an impeccable-looking site, experts, in general, will not allow you to build such a house as the owners intended. For example, a house with a basement was planned, and a high GWL forces specialists to recommend not to do this, therefore, instead of the originally planned strip foundation with a basement, they will recommend a pile foundation without underground facilities. There is no reason not to trust both these studies and specialists, since they have indisputable tools in their hands - measurements, drilling, laboratory experiments, statistics and calculations.

Of course, geological and geodetic surveys are not done free of charge, and they are done at the expense of the developer and they are mandatory on a new site. This fact is often the subject of indignation of some owners, but it should be understood that this procedure will help save a lot of money during the construction and further operation of the house, as well as maintaining the site in good condition. Therefore, this seemingly unnecessary and expensive bureaucracy is necessary and very useful.

If the site is purchased with existing buildings that have been in operation for at least a few years, then you can also order geological and geodetic surveys, but you can do without them, and learn about groundwater, its seasonal rise and unpleasant impact on human life on other grounds. Of course, this will be with a certain degree of risk, but in most cases it works. What you should pay attention to?

• First of all, this is communication with the former owners of the site. It is clear that it is not always in their interests to talk in detail about problems with flooding, but, nevertheless, you can always find out if any drainage measures have been taken. This will not be hidden for anything.
• Inspection of the basement can also tell a lot about something. Regardless of whether cosmetic repairs were made there. If there is an increased level of humidity in the premises, then this will be immediately felt.

• Getting to know your neighbors and interviewing them can be much more informative than talking to the former owners of the site and the house.
• If there are wells or wells on your site and neighboring ones, then the water level in them will eloquently report on the GWL. Moreover, it is desirable to observe how the level changes in different seasons. Theoretically, the maximum water should rise in the spring after the snow has melted. In summer, if there were dry periods, the groundwater level should fall.
• Plants growing on the site can also “tell” a lot to the owner. The presence of plants such as cattail, reeds, sedge, horse sorrel, nettle, hemlock, foxglove indicate that groundwater is at a level of no more than 2.5-3 meters. If even during a drought these plants continue their rapid growth, then this once again indicates the proximity of water. If licorice or wormwood grow on the site, then this is evidence that the water is at a safe depth.

• Some sources speak of an old way of determining the level of groundwater, which was used by our ancestors before building a house. To do this, a piece of turf was removed in the area of ​​interest and a shallow hole was dug, on the bottom of which a piece of wool was laid, an egg was placed on it, and covered with an inverted clay pot and the removed turf. After dawn and sunrise, the pot was removed and watched as the dew fell. If the egg and wool are in dew, then the water is shallow. If dew fell only on wool, then there is water, but it is at a safe depth. If both the egg and the wool are dry, then the water is very deep. It may seem that this method is akin to quackery or shamanism, but in fact it has an absolutely correct explanation, from the point of view of science.
• The growth of bright grass on the site even during a drought, as well as the appearance of fog in the evening hours, indicates the proximity of groundwater.
• The best way to independently determine the groundwater level at the site is to drill test wells. To do this, you can use a regular garden drill with extension cords. Drilling is best done during the highest rise of water, that is, in the spring after the snow melts. First of all, wells should be made at the construction site of a house or an existing building. The well should be drilled to the depth of the foundation plus 50 cm. If water begins to appear in the well immediately or after 1-2 days, this indicates that drainage measures are mandatory.

Beginner's Geologist's Kit - Garden Drill with Extension

• If, after rain, puddles stagnate on the site, then this may indicate the proximity of groundwater, as well as the fact that the soil is clayey or heavy loamy, which prevents the water from going deep into the ground. In this case, drainage is also necessary. It will also be very useful to update the fertile soil to a lighter one, then there will be no problems with growing most garden and garden plants.

Even a very high level of groundwater in the area, although it is a big problem, is a problem that can be completely solved with the help of well-calculated and well-executed drainage. Let's give a good example - more than half of the territory of Holland lies below sea level, including the capital - the famous Amsterdam. The groundwater level in this country can be at a depth of several centimeters. Those who have been to Holland noticed that after rain there are puddles that do not soak into the ground, because they simply have nowhere to soak. Nevertheless, in this cozy country, the issue of draining the land is being solved with the help of a set of measures: dams, dams, polders, locks, canals. The Netherlands even has a special department - Watershap, which deals with flood protection. The abundance of many windmills in this country does not at all mean that they grind grain. Most mills are pumping water.

We do not call for a special purchase of a site with a high level of groundwater, on the contrary, this should be avoided by all possible means. And the example of Holland was given only so that readers could understand that there is a solution to any problem with groundwater. Moreover, in most of the territory of the former USSR, settlements and summer cottages are located in areas where the groundwater level is within acceptable limits, and you can cope with seasonal rises on your own.

Types of drainage systems

There are a great variety of drainage systems and their varieties. Moreover, in different sources, their classification systems may differ from each other. We will try to talk about the simplest, from a technical point of view, drainage systems, but at the same time effective ones that will help solve the problem of removing excess water from the site. Another argument in favor of simplicity is that the fewer elements any system has and the more time it can do without human intervention, the more reliable it will be.

Surface drainage

This type of drainage is the simplest, but, nevertheless, quite effective. It is intended mainly for the removal of water coming in the form of precipitation or snowmelt, as well as for the removal of excess water during any technological processes, for example, when washing cars or garden paths. Surface drainage is done in any case around buildings or other structures, sites, places of exit from the garage or yard. Surface drainage is of two main types:

• Point drainage designed to collect and drain water from a specific place. This type of drainage is also called local drainage. The main locations for point drainage are under roof gutters, in pits in front of doors and garage doors, and at the locations of irrigation taps. And also point drainage, in addition to its direct purpose, can complement another type of surface drainage system.

Rain inlet - the main element of point surface drainage

• Linear drainage needed to remove water from a larger area compared to a point. It is a collection trays And channels, mounted with a slope, equipped with various elements: sand traps (sand traps), protective grilles , performing a filtering, protective and decorative function. Trays and channels can be made from a variety of materials. First of all, it is plastic in the form of polyvinyl chloride (PVC), polypropylene (PP), low-pressure polyethylene (HDPE). And also materials such as concrete or polymer concrete are widely used. Grates are most often used plastic, but in those areas where increased load is expected, stainless steel or even cast iron products can be used. Work on the organization of linear drainage requires concrete preparation of the base.

Obviously, any good surface drainage system almost always combines elements of point and linear. And all of them are combined into a common drainage system, which may also include another subsystem, which we will consider in the next section of our article.

rain gutter prices

storm water inlet

deep drainage

In most cases, surface drainage alone cannot be dispensed with. To qualitatively solve the problem, we need a different type of drainage - deep, which is a system of special drainage pipes (drains) , laid in those places where it is required to lower the level of groundwater or divert water from the protected area. Drains are laid with a slope to the side collector, well , artificial or natural reservoir on the site or beyond. Naturally, they are laid below the level of the base of the foundation of the protected building or along the perimeter of the site at a depth of 0.8-1.5 meters to lower the groundwater level to non-critical values. Drains can also be laid in the middle of the site with a certain interval, which is calculated by experts. Typically, the interval between the pipes is 10-20 meters, and they are laid in the form of a Christmas tree, directed to the main outlet pipe-collector. It all depends on the level of groundwater and their quantity.

When laying drains in trenches, it is imperative to use all the features of the site relief. Water will always move from a higher place to a lower one, so the drains are laid in the same way. It is much more difficult if the site is absolutely flat, then the pipes are given the desired slope by giving a certain level to the bottom of the trenches. It is customary to make a slope of 2 cm per 1 meter of pipe for clay and loamy soils and 3 cm per 1 meter for sandy soils. Obviously, with sufficiently long drains, it will be difficult to maintain the desired slope on a flat area, since the level difference will already be 20 or 30 cm per 10 meters of the pipe, so the necessary measure is the organization of several drainage wells that will be able to receive the required volume of water.

It should be noted that even with a smaller slope, water, even at 1 cm per 1 meter or less, will still, obeying the laws of physics, try to go below the level, but the flow rate will be less, and this can contribute to silting and clogging of drains. And any owner who has laid sewer or drainage pipes at least once in his life knows that it is much more difficult to maintain a very small slope than a larger one. Therefore, you should not be “embarrassed” in this matter and boldly set a slope of 3, 4 and even 5 cm per meter of the drainage pipe, if the length and the planned difference in the depth of the trench allow.

Drainage wells are one of the most important components of deep drainage. They can be of three main types:

• Rotary wells – suit where the drains make a turn or there is a connection of several elements. These elements are needed for the revision and cleaning of the drainage system, which must be done periodically. They can be as small in diameter, which will only allow cleaning and washing with a jet of water under pressure, but they can also be wide, which provide human access.

• Water intake wells - their purpose is absolutely clear from their name. In those areas where it is not possible to divert water into the depths or beyond, it becomes necessary to collect water. These wells are designed for just that. Previously, they were mainly a structure made of cast-in-place concrete, concrete rings or bricks plastered with cement mortar. Now, plastic containers of various sizes are most often used, which are protected from clogging or silting with geotextiles and sprinkling of crushed stone or gravel. Water collected in a water intake well can be pumped out of the site using special submersible drainage pumps, can be pumped out and taken out by tankers, or can be settled in a well or pool for further irrigation.

• absorption wells designed to drain water in the event that the terrain of the site does not allow moisture to be removed beyond its limits, but the underlying soil layers have good absorbency. These soils include sandy and sandy loam. Such wells are made of large diameters (about 1.5 meters) and depths (at least 2 meters). The well is filled with filter material in the form of sand, sand-gravel mixture, crushed stone, gravel, broken brick or slag. To prevent the ingress of eroded fertile soil or various blockages from above, the well is also covered with fertile soil. Naturally, the side walls and the bottom are protected by sprinkling. Water, falling into such a well, is filtered by its contents and goes deep into sandy or sandy loamy soils. The ability of such wells to remove water from the site may be limited, so they are arranged when the expected throughput should not exceed 1-1.5 m 3 per day.

Of the drainage systems, the main and most important is deep drainage, since it is it that provides the necessary water regime for both the site and all the buildings located on it. Any mistake in the design and installation of deep drainage can lead to very unpleasant consequences, which can lead to the death of plants, flooding of basements, destruction of house foundations, and uneven drainage of the site. That is why it is recommended not to neglect geological and geodetic studies and ordering a drainage system project from specialists. If it is possible to correct flaws in surface drainage without a strong violation of the landscape of the site, then with deep drainage everything is much more serious, the price of a mistake is too high.

Well prices

Overview of accessories for drainage systems

For self-execution of the drainage of the site and the buildings located on it, you need to find out what components will be required for this. Of the widest selection of them, we have tried to show the most used at the present time. If earlier the market was dominated by Western manufacturers, who, as monopolists, dictated high prices for their products, now a sufficient number of domestic enterprises offer their products, which are in no way inferior in quality.

Details for surface drainage

For point and linear surface drainage, the following parts can be used:

Image	Name, manufacturer	Purpose and description
	Tray drainage concrete 1000*140*125 mm with a steel stamped galvanized lattice. Production - Russia.	Designed for surface water drainage. Capacity 4.18 l/s, able to withstand loads up to 1.5 tons (A15).	880 rub.
	Concrete drainage tray with cast-iron grate, dimensions 1000*140*125 mm. Production - Russia.	The purpose and throughput are the same as in the previous example. Able to withstand loads up to 25 tons (C250).	1480 rub.
	Concrete drainage tray with steel galvanized mesh grid, dimensions 1000*140*125 mm. Production - Russia.	The purpose and throughput are the same. Able to withstand loads up to 12.5 tons (B125).	1610 rub.
	Polymer concrete drainage tray 1000*140*70 mm with plastic grating. Production - Russia.	The purpose is the same, the throughput is 1.9 l / s. Able to withstand loads up to 1.5 tons (A15). The material combines the advantages of plastic and concrete.	820 rub.
	Polymer concrete drainage tray 1000*140*70 mm with cast-iron grate. Production - Russia.	throughput is the same. Able to withstand up to 25 tons of load (C250).	1420 rub.
	Polymer concrete drainage tray 1000*140*70 mm with steel mesh grating. Production - Russia.	throughput is the same. Able to withstand up to 12.5 tons of load (B125).	1550 rub.
	Tray plastic drainage 1000*145*60 mm with a galvanized stamped lattice. Production - Russia.	Made from frost-resistant polypropylene. Throughput 1.8 l/sec. Able to withstand loads up to 1.5 tons (A15).	760 rub.
	Plastic drainage tray 1000*145*60 mm with cast-iron grate. Production - Russia.	Throughput 1.8 l/sec. Able to withstand loads up to 25 tons (C250).	1360 rub.
	Completed plastic rainwater inlet (siphon-partitions 2 pcs., Waste basket - 1 pc.). Size 300*300*300 mm. With plastic grid. Production - Russia.	Designed for point drainage of water flowing from the roof through the downpipe, and can also be used to collect water under yard, garden watering taps. Can be connected to fittings with diameters of 75, 110, 160 mm. Removable basket provides quick cleaning. Withstands loads up to 1.5 tons (A15).	For a set together with siphon partitions, a waste basket and a plastic grate - 1000 rubles.
	Completed plastic rainwater inlet (siphon-partitions 2 pcs., Waste basket - 1 pc.). Size 300*300*300 mm. With cast-iron grate "Snowflake". Production - Russia.	The purpose is similar to the previous one. Withstands loads up to 25 tons (C250).	For a set together with siphon partitions, a waste basket and a cast-iron grate - 1550 rubles.
	Sand trap - plastic with a galvanized steel grate. Dimensions 500*116*320 mm.	Designed to collect dirt and debris in surface linear drainage systems. It is installed at the end of the line of gutters (trays) and later it joins the pipes of the storm sewer system with a diameter of 110 mm. Able to withstand loads up to 1.5 tons (A15).	For a set together with gratings 975 rubles.

In the table, we deliberately showed Russian-made trays and storm water inlets, made of materials that differ from each other and have different configurations. It is also worth noting that the trays have different widths and depths and, accordingly, their throughput is also not the same. There are a lot of options for the materials from which they are made and sizes, there is no need to list them all, since it depends on many factors: the required throughput, the expected load on the soil, the specific scheme for implementing the drainage system. That is why it is best to entrust the calculations of the drainage system to specialists who will calculate both the required size and quantity, and select the components.

There was absolutely no need to talk about possible accessories for drainage trays, storm water inlets and sand traps in the table, since in each individual case they will be different. When buying, if there is a system project, the seller will always tell you the ones you need. They can be end caps for trays, mounts for gratings, various corner and transition elements, reinforcing profiles, and others.

A few words should be said about sand traps and storm water inlets. If the surface linear drainage around the house is implemented with storm water inlets in the corners (and this is usually done), then sand traps will not be required. Rain inlets with siphon partitions and waste baskets do an excellent job with their role. If the linear drainage does not have storm water inlets and goes into the sewer drainage pipe, then a sand trap is required. That is, any transition from drainage trays to pipes must be done either with the help of a storm inlet or a sand trap. Only this way and not otherwise! This is done so that sand and various heavy debris do not get into the pipes, as this can lead to their rapid wear, and over time, both they and the drainage wells will become clogged. It is hard to disagree that it is easier to periodically remove and wash the baskets while on the surface than to go down into the wells.

Surface drainage also includes wells and pipes, but they will be discussed in the next section, since, in principle, they are the same for both types of systems.

Details for deep drainage

Deep drainage is a more complex engineering system that requires more details. In the table we present only the main ones, since all their diversity will take up a lot of space and attention of our readers. If desired, it will not be difficult to find catalogs of manufacturers of these systems, select the necessary parts and accessories for them.

Image	Name and manufacturer	Purpose and description	Approximate price (as of October 2016)
	Drainage pipe with a diameter of 63 mm made of HDPE corrugated single-walled in a geotextile filter. Producer "Sibur", Russia.	Designed to remove excess moisture from foundations and sites. Wrapped with geotextile to prevent clogging of pores with soil, sand, which prevents clogging and silting. They have a full (circular) perforation. Made from low pressure polyethylene (HDPE). Rigidity class SN-4. Depth of laying up to 4 m.	For 1 r.p. 48 rub.
	Drainage pipe with a diameter of 110 mm made of HDPE corrugated single-walled in a geotextile filter. Producer "Sibur", Russia.	similar to above	For 1 r.p. 60 rub.
	Drainage pipe with a diameter of 160 mm made of HDPE corrugated single-walled in a geotextile filter. Producer "Sibur", Russia.	similar to above	For 1 r.p. 115 rub.
	Drainage pipe with a diameter of 200 mm made of HDPE corrugated single-walled in a geotextile filter. Producer "Sibur", Russia.	similar to above	For 1 r.p. 190 rub.
	Single-wall corrugated drainage pipes made of HDPE with a coconut coir filter with diameters of 90, 110, 160, 200 mm. Country of manufacture - Russia.	Designed to remove excess moisture from foundations and sites on clay and peat soils. Coconut coir has increased reclamation and strength compared to geotextiles. They have circular perforations. Rigidity class SN-4. Depth of laying up to 4 m.	219, 310, 744, 1074 rubles. for 1 r.m. (depending on diameter).
	Two-layer drainage pipes with Typar SF-27 geotextile filter. The outer layer of HDPE is corrugated, the inner layer of HDPE is smooth. Diameters 110, 160, 200 mm. Country of origin - Russia.	Are intended for removal of excess moisture from the bases and sites on all types of soils. They have a full (circular) perforation. The outer layer protects against mechanical stress, and the inner layer allows more water to be removed due to its smooth surface. The two-layer design has a stiffness class of SN-6 and allows you to lay pipes at a depth of up to 6 meters.	160, 240, 385 rubles. for 1 r.m. (depending on diameter).
	PVC pipes for sewerage are smooth with a socket with an outer diameter of 110, 125, 160, 200 mm, length 1061, 1072, 1086, 1106 mm, respectively. Country of origin - Russia.	Designed for organizing an external sewer system, as well as storm sewer or drainage systems. They have a stiffness class of SN-4, which allows them to be laid at a depth of up to 4 meters.	180, 305, 270, 490 rubles. for pipes: 110*1061 mm, 125*1072 mm, 160*1086 mm, 200*1106 mm respectively.
	Well shafts with a diameter of 340, 460, 695, 923 mm from HDPE. Country of origin - Russia.	Are intended for creation of drainage wells (rotary, water intake, absorption). They have a two-layer construction. Ring stiffness SN-4. The maximum length is 6 meters.	950, 1650, 3700, 7400 rubles for wells with diameters of 340, 460, 695, 923 mm, respectively.
	Bottom-plug of wells with diameters of 340, 460, 695, 923 mm from HDPE. Country of origin - Russia.	Designed to create drainage wells: rotary or water intake.	940, 1560, 4140, 7100 for wells with diameters of 340, 460, 695, 923 mm, respectively.
	Inserts into the well in place with diameters of 110, 160, 200 mm. Country of origin - Russia.	Designed for insertion into a well at any level of sewer or drainage pipes of appropriate diameters.	350, 750, 2750 rubles for inserts with diameters of 110, 160, 200 mm, respectively.
	Hatch polymer concrete for drainage wells with a diameter of 340 mm. Country of origin - Russia.		500 rub.
	Hatch polymer concrete for drainage wells with a diameter of 460 mm. Country of origin - Russia.	It is intended for installation on drainage wells. Withstands loads up to 1.5 tons.	850 rub.
	Polyester geotextile with a density of 100 g/m². Country of origin - Russia.	Used to create drainage systems. It is not subject to rotting, influence of a mold, rodents and insects. Roll length from 1 to 6 m.	20 rub. for 1 m².

The presented table shows that the cost of even Russian-made parts for drainage systems can hardly be called cheap. But the effect of their use will delight the owners of the site for at least 50 years. It is about this service life that the manufacturer claims. Considering that the material for manufacturing drainage parts is absolutely inert with respect to all substances found in nature, it can be assumed that the service life will be much longer than stated.

We deliberately did not indicate the previously widely used asbestos-cement or ceramic pipes in the table, since apart from the high price and difficulties in transportation and installation, they will not bring anything. This is yesterday's age.

To create drainage systems, there are still a lot of components from various manufacturers. These include tray parts, which can be throughput, connecting, prefabricated and dead-end. They are designed to connect drainage pipes of various diameters to wells. They provide connections for drainage pipes at various angles.

With all the obvious advantages of tray parts with pipe sockets, their price is very high. For example, the part shown in the figure above costs 7 thousand rubles. Therefore, in most cases, inserts into the well are used, as indicated in the table. Another advantage of tie-ins is that they can be done at any level and at any angle to each other.

In addition to those parts for drainage systems that are indicated in the table, there are many others that are selected by calculation and during installation on site. These may include various cuffs and o-rings, couplings, tees and crosses, check valves for drainage and sewer pipes, eccentric transitions and necks, bends, plugs and much more. Their correct selection should be dealt with, first of all, during the design, and then make adjustments during installation.

Video: How to choose a drainage pipe

Video: Drainage wells

If readers find articles on drainage on the Internet that say that it is easy to make drainage with your own hands, then we advise you to immediately close this article without reading it. Making drainage with your own hands is not an easy task. But, the main thing is that it is possible if you do everything consistently and correctly.

Site drainage design

The drainage system is a complex engineering object that requires an appropriate attitude. Therefore, we recommend that our readers order the design of the drainage of the site from professionals who will take into account absolutely everything: the relief of the site, and the existing (or planned) buildings, and the composition of the soil, and the depth of the GWL, and other factors. After the design, the customer will have a set of documents in his hands, which includes:

• Site plan with its relief.
• A scheme for laying pipes for wall or ring drainage, indicating the section and type of pipes, the depth of occurrence, the required slopes, and the location of the wells.
• The drainage scheme of the site, also indicating the depth of the trenches, types of pipes, slopes, the distance between adjacent drains, the location of rotary or water intake wells.

It will be difficult to independently make a detailed design of the drainage system without knowledge and experience. That is why you should turn to professionals

• Scheme of surface point and linear drainage indicating the size of trays, sand traps, storm water inlets, used sewer pipes, location of water intake wells.
• Transverse dimensions of trenches for near-wall and deep drainage, indicating the depth, material and thickness of the backfill, type of geotextile used.
• Calculation of necessary components and materials.
• An explanatory note to the project describing the entire drainage system and the technology for performing work.

The project of the drainage system of the site is much lower than the architectural one, so we once again strongly advise you to contact the specialists. This minimizes the likelihood of errors during self-arrangement of drainage.

Wall drainage equipment at home

To protect the foundations of houses from the effects of groundwater, the so-called wall drainage is made, which is located around the entire house on its outer side at some distance from the base of the foundation. usually it is 0.3-0.5 m, but in any case not more than 1 meter. Wall drainage is done even at the stage of building a house, along with measures for warming and waterproofing the foundation. When is this type of drainage necessary anyway?

Prices for drainage systems

• When the house has a basement.

• When the buried parts of the foundation are at a distance of no more than 0.5 meters above the groundwater level.
• When a house is built on clay or loamy soils.

All modern house designs almost always provide wall drainage. An exception can only be those cases when the foundation is laid on sandy soils that do not freeze through more than 80 cm.

A typical wall drainage design is shown in the figure.

At some distance from the base of the foundation, approximately 30 cm below its level, a leveling layer of sand 10 cm is made, on which a geotextile membrane with a density of at least 150 g / m² is laid, on which a layer of crushed stone of a fraction of 20-40 mm with a thickness of at least 10 cm is poured. Instead of crushed stone, washed gravel may well be used. Crushed stone is better to use granite, but not limestone, since the latter tends to gradually erode with water. A drainage pipe wrapped with geotextile is laid on a crushed stone pillow. The pipes are given the desired slope - at least 2 cm per 1 linear meter of the pipe.

In the places where the pipe turns, inspection and inspection wells are necessarily made. The rules allow them to be done through one turn, but practice suggests that it is better not to save on this and put them on every turn. The slope of the pipes is done in one direction (in the figure from point K1, through points K2 and K3, to point K4). In this case, it is necessary to take into account the terrain. It is assumed that point K1 is at the highest point, and K4 at the lowest.

Drains are inserted into wells not from the very foundation, but with an indent of at least 20 cm from the bottom. Then the small debris or silt that has fallen will not linger in the pipes, but will settle in the well. In the future, when revising the system, you can wash out the silted bottom with a strong jet of water, which will carry away everything unnecessary. If the soil in the area where the wells are located has a good absorbing capacity, then the bottom is not made. In all other cases, it is better to equip the wells with a bottom.

A layer of crushed stone or washed gravel with a thickness of at least 20 cm is again poured over the drains, and then it is wrapped around with the previously laid geotextile membrane. On top of such a “wrapped” structure made of a drainage pipe and rubble, a backfill of sand is made, and on top, after it is compacted, a blind area of ​​​​the building is already organized, which is also called upon, but already in the system of surface linear drainage. Even if atmospheric water enters from the outside of the foundation, then, having passed through the sand, it will fall into the drains and eventually merge into the main collector well, which can be equipped with a pump. If the relief of the site allows, then an overflow is made from the collector well without a pump, which removes water outside into a gutter, an artificial or natural reservoir, or a storm sewer system. Under no circumstances should drainage be connected to a conventional sewer system.

If groundwater begins to "support" from below, then they, first of all, impregnate the sandy preparation and crushed stone in which the drains are located. The speed of water movement along the drains is higher than in the ground, so the water is quickly removed and drained into a collector well, which is laid lower than the drains. It turns out that inside a closed circuit of drainage pipes, water simply cannot rise above the level of the drains, which means that the base of the foundation and the floor in the basement will be dry.

Such a wall drainage scheme is very often used and works very effectively. But it has a significant drawback. This is backfilling of the entire sinus between the foundation and the edge of the pit with sand. Given the considerable volume of the sinus, you will have to pay a tidy sum for this filling. But there is a beautiful way out of this situation. In order not to backfill with sand, you can use a special profiled geomembrane, which is a sheet of HDPE or PVD with various additives, which has a relief surface in the form of small truncated cones. When the underground part of the foundation is pasted over with such a membrane, it performs two main functions.

• The geomembrane itself is an excellent waterproofing agent. It does not allow moisture to penetrate to the walls of the underground foundation structure.
• The relief surface of the membrane ensures that the water that appears on it flows down freely, where it is “intercepted” by the laid drains.

The design of wall drainage using a geomembrane is shown in the following figure.

On the outer wall of the foundation, after the measures and insulation (if necessary), the geomembrane is glued or mechanically attached with the relief part (pimples) outward. A geotextile fabric with a density of 150-200 g / m² is fixed on top of it, which will prevent soil particles from clogging the relief part of the geomembrane. Further organization of drainage is usually carried out: a drain is placed on a layer of sand, covered with crushed stone and wrapped with geotextile. Only backfilling of the sinuses is not done with sand or gravel, but with ordinary soil excavated when digging a pit or clay, which is much cheaper.

Drainage of water, "supporting" the foundation from below, proceeds as in the previous case. But water that has entered the wall from the outside through moist soil or penetrated into the gap between the foundation and the soil will follow the path of least resistance: seep through the geotextile, flow freely along the relief surface of the geomembrane, pass through rubble and fall into the drain. Foundations protected in this way will not be threatened for a minimum of 30-50 years. In the basement floors of such houses it will always be dry.

Consider the main stages of creating a wall drainage system at home.

Image	Description of actions
	After the measures for the construction of the foundation, its primary coating, and then rolled waterproofing and insulation have been carried out, the geomembrane is glued with the relief part outward on the outer wall of the foundation, including its sole, using a special mastic that does not corrode the expanded polystyrene. The upper part of the membrane should protrude beyond the level of the future backfill by at least 20 cm, and the lower part should reach the very bottom of the foundation, including the sole.
	The joints of most geomembranes have a special lock, which is "snapped" by overlapping one sheet over another, and then tapping with a rubber mallet.
	A geotextile fabric with a density of 150-200 g/m² is attached over the geomembrane. It is better to use not needle-punched, but thermally bonded geotextiles, as it is less prone to clogging. For fixing, dish-shaped dowels are used. The step of fastening the dowels is no more than 1 m horizontally and no more than 2 m vertically. The overlap of adjacent geotextile sheets on each other is at least 10-15 cm. Dish-shaped dowels should fall at the junction.
	In the upper part of the geomembrane and geotextile, it is recommended to use a special mounting strip, which will press both layers to the foundation structure.
	The bottom of the pit from the outside of the foundation is cleaned to the required level. The level can be controlled with a theodolite with a measuring bar, a laser level and an improvised wooden bar with marked marks, stretched and set with a tensioned cord using a hydraulic level. You can also “beat off” a horizontal line on the wall and measure the depth with a tape measure.
	Washed sand is poured at the bottom with a layer of at least 10 cm, which is wetted with water and rammed mechanically or manually until there are practically no traces left when walking.
	In the designated places, inspection and inspection wells are installed. To do this, it is enough to use mines with a diameter of 340 or 460 mm. Having measured the desired length, they can be cut either with a conventional hacksaw for wood, or with an electric jigsaw, or with a reciprocating saw. Initially, the wells must be cut 20-30 cm more than the estimated length, and later, when designing the landscape, already fit it under it.
	Bottoms are installed on the wells. To do this, in single-layer wells (for example, Wavin), a rubber cuff is placed in the rib of the body, then it is lubricated with soapy water and the bottom is put on. It must go in with force.
	In Russian-made two-layer wells, before installing the cuff, it is necessary to cut a strip of the inner layer with a knife, and then do the same as in the previous case.
	Wells are installed in their intended places. Sites for their installation are compacted and leveled. On their side surfaces, marks are made for the entrance and exit of the centers of drains (taking into account slopes of 2 cm per 1 linear meter of pipe). We remind you that the entrances and exits of drains must be at least 20 cm from the bottom.
	For the convenience of inserting couplings, it is better to place the wells horizontally and make holes corresponding to the coupling with a crown with a center drill. In the absence of a crown, you can make holes with a jigsaw, but this requires certain skills.
	After that, the edges are cleaned of burrs with a knife or brush.
	The outer rubber cuff of the coupling is placed inside the hole. It should equally go inside the well and stay outside (about 2 cm each).
	The inner surface of the rubber cuff of the coupling is lubricated with soapy water, and then the plastic part is inserted until it stops. The joints of the rubber part of the coupling to the well can be smeared with a waterproof sealant.
	Wells are installed in their places and aligned vertically. Geotextiles are laid out on a sand cushion. Granite crushed stone of a fraction of 5-20 mm or washed gravel with a layer of at least 10 cm is poured on it. In this case, the necessary slopes of the drainage pipes are taken into account. Crushed stone is leveled and compacted.
	Perforated drainage pipes of the required size are measured and cut. Pipes are inserted into couplings cut into wells after lubricating the cuff with soapy water. Their slope is checked.
	A layer of crushed stone or gravel of at least 20 cm is poured on top of the drains. Then the edges of the geotextile fabric are wrapped on top of each other and a 20 cm layer of sand is sprinkled on top.
	In the intended place, a pit is dug for the collector well of the drainage system. The level of its occurrence, of course, must be below the lowest drain in order to receive water from the wall drainage. To this pit, a trench is dug from the lower level of the inspection and inspection well for laying a sewer pipe.
	Shafts with diameters of 460, 695 and even 930 mm can be used as a collector well. A prefabricated well made of reinforced concrete rings can also be equipped. Inserting a sewer pipe into a receiving collector well is done in exactly the same way as drains.
	The sewer pipe leading from the lower wall drainage well to the collector well is laid on a 10 cm sand cushion and sprinkled with sand of at least 10 cm thickness on top. After compacting the sand, the trench is covered with soil.
	The system is checked for functionality. To do this, water is poured into the topmost well in terms of level. After filling the bottom, water should begin to flow through the drains into other wells and, after filling their bottoms, eventually flow into the collector well. There should be no reverse current.
	After checking the performance of the sinuses between the edge of the pit, they are covered with soil. It is preferable to use quarry clay for this, which will create a waterproof lock around the foundation.
	The wells are covered with lids to prevent clogging. Final pruning and installation of covers should be done along with landscaping.

The collection well can be equipped with a check valve, which, even if it is overflowing, will not allow water to flow back into the drains. And also in the well can be automatic. When the GWL rises to critical values, water will collect in the well. The pump is set up so that when a certain level is exceeded in the well, it will turn on and pump water out of the site or into other containers or reservoirs. Thus, the GWL in the foundation area will always be lower than the laid drains.

It happens that one collector well is used for the wall drainage system and the surface one. Experts do not recommend doing this, since during intense snowmelt or heavy rains, a very large amount of water will be collected in a short time, which will only interfere with inspecting the GWL in the foundation area. Water from precipitation and melted snow is best collected in separate containers and used for irrigation. In case of overflow of storm wells, water from them can be pumped in the same way to another place with a drainage pump.

Video: Wall drainage at home

Ring drainage equipment at home

Annular drainage, unlike wall drainage, is located not close to the foundation structure, but at some distance from it: from 2 to 10 meters or more. In what cases is ring drainage arranged?

• If the house has already been built and any intervention in the foundation structure is undesirable.
• If the house does not have a basement.
• If the house or group of buildings is built on sandy or sandy loamy soils that have good water permeability.
• If other types of drainage cannot cope with the seasonal rise of groundwater.

Regardless of the fact that ring drainage is much simpler in practical implementation, it should be treated more seriously than wall drainage. Why?

• A very important characteristic is the depth of the drains. In any case, the laying depth must be greater than the depth of the base of the foundation or the level of the basement floor.
• The distance from the foundation to the drain is also an important characteristic. The more sandy the soil, the greater the distance should be. And vice versa - the more clay soils, the closer the drains can be located to the foundation.
• When calculating the ring foundation, the level of groundwater, its seasonal fluctuations and the direction of their inflow are also taken into account.

Based on the foregoing, we can safely say that it is better to entrust the calculation of the annular drainage to specialists. It would seem that the closer the drain is to the house and the deeper it is laid, the better it will be for the protected structure. It turns out not! Any drainage changes the hydrogeological situation in the foundation area, which is far from always good. The task of drainage is not to completely drain the site, but to lower the GWL to such values ​​that will not interfere with human and plant life. Drainage is a kind of contract with the forces of Mother Nature, and not an attempt to "rewrite" existing laws.

One of the options for the device of the annular drainage system is shown in the figure.

It can be seen that a trench has been dug around the house outside the blind area to such a depth that the upper part of the drainage pipe lies 30-50 cm below the lowest point of the foundation. The trench is lined with geotextile and the pipe itself is also in a shell of it. The minimum underlying layer of crushed stone should be at least 10 cm. The minimum slope of drains with a diameter of 110-200 mm is 2 cm per 1 linear meter of pipe. The figure shows that the entire trench is covered with rubble. This is quite acceptable and does not contradict anything but common sense, in terms of excessive spending.

The diagram shows that the inspection and control wells are installed through one turn, which is quite acceptable if the drainage pipe is laid in one piece, without any fittings. But still it is better to do them at every turn. This will greatly facilitate the maintenance of the drainage system over time.

An annular drainage system can perfectly "get along" with a system of surface point and linear drainage. In one trench, drains can be laid at the lower level, and sewer pipes leading from the trays and storm water inlets to the well for collecting rain and melt water can be laid next to them or on top in a layer of sand. If the path of both one and the other leads to one collector catchment well, then this is generally wonderful, the number of earthworks is reduced significantly. Although, we recall that we recommended collecting these waters separately. They can be collected together in only one case - if all water from precipitation and extracted from the soil is removed (naturally or forcibly) from the site into a collective storm sewer system, gutter or reservoir.

When organizing ring drainage, a trench is first dug to the estimated depth. The width of the trench in the area of ​​​​its bottom should be at least 40 cm; a certain slope is immediately given to the bottom of the trench, the control of which is most convenient to carry out with a theodolite, and in its absence, a horizontally stretched cord and a measuring rod from improvised means will help.

Washed sand is poured at the bottom with a layer of at least 10 cm, which is carefully rammed. It is obvious that it is impossible to do this in a narrow trench in a mechanized way, therefore, a manual rammer is used.

Installation of wells, tie-in couplings, adding crushed granite or gravel, laying and connecting drains is done in exactly the same way as when organizing wall drainage, so there is no point in repeating. The difference is that with ring drainage, it is better to fill the trench after crushed stone and geotextiles not with soil, but with sand. Only the upper fertile layer of soil is poured, about 10-15 cm. Then, already with the landscape equipment of the site, the places for laying drains are taken into account and trees or shrubs with a powerful root system are not planted in these places.

Video: Drainage around the house

Surface point and line drainage equipment

As in all cases, a surface drainage system can only be successfully installed if there is a project or at least a self-made plan. On this plan, it is necessary to take into account everything - from water intake points to a tank where rain and melt water will merge. In this case, it is necessary to take into account the slopes of pipelines and trays, the direction of movement along the trays.

The surface drainage system can be installed with an existing blind area, paths made of paving slabs or paving stones. It is possible that one of their parts will have to be intervened, but this still does not require complete dismantling. Consider an example of the installation of a surface drainage system using the example of polymer concrete trays and sand traps (sand traps) and sewer pipes.

To carry out the work you will need a very simple set of tools:

• Shovels shovel and bayonet;
• Building bubble level from 60 cm long;
• Bench hammer;
• Rubber hammer for laying tiles or paving stones;
• Construction marking cord and a set of stakes made of wood or pieces of reinforcement;
• Trowel and spatulas;
• Roulette;
• Construction knife;
• Chisel;
• Angle grinder (grinder) with discs of at least 230 mm for stone and metal;
• Container for preparation of solutions.

We present the further process in the form of a table.

Image	Process description
	Given the plan or design of surface drainage, it is necessary to determine the points of water discharge, that is, those places where water collected from the surface will go into the sewer pipeline leading to the drainage well. The depth of this pipeline should be lower than the freezing depth of the soil, which is 60-80 cm for most populated climatic zones in Russia. It is in our interests to minimize the number of discharge points, but to ensure the required drainage capacity.
	Discharge of water into the pipeline must be done either through sand traps or through storm water inlets to ensure the filtering of debris and sand. First of all, it is necessary to provide for their connection using standard shaped elements of external sewerage to the pipeline and try on these elements at the installation site.
	It is better to foresee the connection of storm water inlets located under the drainpipes in advance, even at the stage of arranging wall drainage, so that when snow melts during the thaw and off-season, the water flowing from the roofs immediately falls into the underground pipeline and would not freeze in trays, on blind areas and paths.
	If it is not possible to install sand traps, then the sewer pipeline can be connected directly to the trays. For this, polymer concrete trays have special technological holes that allow you to connect a vertical pipeline.
	Some manufacturers have special baskets fixed in the vertical water outlet, which protect the drainage system from clogging.
	Most plastic trays, in addition to a vertical connection, can also have a side connection. But this should be done only when there is confidence in the purity of the water being drained, since it is much more difficult to clean drainage wells and catchment tanks than baskets.
	To install surface drainage elements, you first need to select the soil to the required depth and width. To do this, with an already existing lawn, the turf is cut to the required width, which is defined as the width of the installed element plus 20 cm - 10 cm on each side. It may be necessary to dismantle the curbs and extreme rows of paving slabs or paving stones.
	In depth, for the installation of drainage elements, it is necessary to choose the soil by the depth of the element plus 20 cm. Of these, 10 cm for sand or crushed stone preparation, and 10 cm for a concrete base. The soil is removed, the base is cleaned and rammed, and further filling is made of crushed stone of a fraction of 5-20 mm. Then pegs are driven in and a cord is pulled, which will determine the level of the installed trays.
	Surface drainage elements are tried on at the installation site. In this case, one should take into account the direction of the water flow, which is usually indicated on the side surface of the trays.
	Holes are made in the drainage elements for connecting sewer pipes. In plastic trays, this is done with a knife, and in polymer concrete trays with a chisel and a hammer.
	When fitting parts, it may be necessary to cut off part of the tray. Plastic are easily cut with a hacksaw, and polymer concrete with a grinder. Galvanized metal gratings are cut with scissors for metal, and cast-iron gratings are cut with a grinder.
	On the last trays, end caps are installed using a special adhesive-sealant.
	To install surface drainage elements, it is best to use ready-made dry mixes of sand concrete M-300, which are in the assortment of many manufacturers. In a suitable container, a solution is prepared, which should be dense in consistency. Installation is best done from discharge points - sand traps. Concrete is laid out on the prepared base.
	Then it is leveled with a trowel and a sand trap is installed on this pillow.
	Then it is exposed along the previously stretched cord. If necessary, the tray is seated in place with a rubber mallet.
	The correctness of the installation is checked by the cord and by the level.
	Trays and sand traps are set so that when the grate is installed, its plane is 3-5 mm below the surface level. Then the water will flow freely into the trays, the gratings will not be damaged by the wheels of the car.
	The sand trap installed according to the level is immediately fixed on the sides with a concrete mixture. The so-called concrete heel is formed.
	Similarly, drainage trays are installed on a concrete base.
	They also align with both cord and level.
	After installation, the joints are covered with a special sealant, which is always offered when buying trays.
	Experienced installers can apply sealant before installing the trays, applying it to the ends even before installation.
	When installing plastic trays in concrete, they can be deformed. Therefore, it is better to install them with installed gratings, which, in order to avoid contamination, are best wrapped with plastic wrap.
	If the surface is flat and has no slopes, then it will be problematic to provide the required slope of the trays. The way out of this situation is to install a cascade of trays of the same width, but different depths.
	After installing all the elements of surface drainage, a concrete heel is formed, and then paving stones or paving slabs are installed in place if they were dismantled. The surface of the paving stones should be 3-5 mm higher than the grate of the drainage tray.
	Between the paving stones and the trays, it is imperative to make a deformation seam. Instead of the recommended rubber cords, you can use a double-folded strip of roofing material and sealant.
	After the concrete has set, after 2-3 days, backfilling of the excavated soil can be done.
	After compacting the soil, the previously removed layer of turf is laid out on top. It must be laid 5-7 cm higher than the rest of the lawn surface, as over time it will compact and settle.
	After flushing the entire surface drainage system and checking its performance, the trays, storm water inlets and sand traps are closed with gratings. It is possible to expose elements to vertical loading only in 7-10 days.

When operating a surface drainage system, it is imperative to periodically clean the storm water inlets and sand traps. If necessary, you can remove the protective grids and rinse the trays themselves with a strong jet of water. Water collected after rains or snowmelt is the most suitable for further use for watering the garden, vegetable garden or lawns. The groundwater collected by a deep drainage system may have a different chemical composition and may not always be used for the same purposes. Therefore, we once again remind and advise our readers to collect groundwater and atmospheric water separately.

Video: Installation of a drainage system

Site deep drainage equipment

We have already described in which cases deep drainage of the site is needed and found out that it is needed almost always in order to forever forget about the problems of stagnant puddles, permanent dirt or the death of various plants that cannot tolerate waterlogged soils. The complexity of deep drainage equipment is that if the site has already been landscaped, trees and shrubs have been planted, there is a well-groomed lawn, then this order will have to be violated at least partially. Therefore, we recommend to immediately organize a deep drainage system on the acquired new construction sites. As in all other cases, the project of such a drainage system must be ordered from specialists. Independent incorrect calculation and execution of the drainage system can lead to the fact that waterlogged places on the site will be adjacent to dry ones.

In areas with a pronounced relief, the drainage system can become a beautiful part of the landscape. To do this, an open channel or a network of channels is organized, through which water can freely leave the site. Rainwater from the roof can also be directed into these channels. But readers will certainly agree with the authors that the presence of a large number of channels will bring more inconvenience than benefits from their contemplation. That is why closed-type deep drainage is most often equipped. Opponents of deep drainage may argue that such systems can lead to excessive drainage of fertile soil, which will negatively affect plants. However, any fertile soils have a very good and useful property - they retain exactly as much water in their thickness as necessary, and plants growing on soils take exactly as much water from it as is necessary for their root system.

The main guiding document for the organization of the drainage system is a graphical plan of the drainage system, which indicates everything: the location of the collector and storage wells, the cross section of the drainage pipes and their depth, the cross section of the drainage trench and other useful information. An example of a drainage system plan is shown in the figure.

Consider the main stages of creating a deep drainage site.

Image	Process description
	First of all, the site is marked, in which the position of the main elements of the drainage system is transferred from the plan to the terrain. Drainage pipe routes are marked with a stretched cord, which can immediately be pulled either horizontally or with a slope, which should be in each of the sections.
	A pit is dug under the storage drainage well of the required depth. The bottom of the pit is compacted and 10 cm of sand is poured and compacted on it. The body of the well is tried on in place.
	A trench is dug in the direction from the well towards the beginning of the main collector pipe, the bottom of which is immediately given the desired slope specified in the project, but not less than 2 cm per 1 linear meter of the pipe. The width of the trench in the bottom area is 40 m. The depth depends on the specific project.
	From the collector trench, trenches are dug for drains, which will be connected to the collector pipe. The bottom of the trenches is immediately given the desired slope. The width of the trenches in the bottom area is 40 cm. The depth is according to the project. On clay and loamy soils, the average depth of drains is 0.6-0.8 meters, and on sandy soils - 0.8-1.2 meters.
	The locations of rotary and collector inspection manholes are being prepared.
	After checking the depth and the required slopes, 10 cm of sand is poured onto the bottom of all trenches, which is then wetted and compacted manually.
	Geotextile is lined at the bottom of the trenches so that it also goes onto the side walls. Depending on the depth of the trench and the width of the geotextile fabric, it is fixed either on the walls of the trench or on top.
	The wells are installed and tried on in their places, the places where the couplings are inserted are marked. Then the wells are removed and the necessary couplings are cut into them to connect the drains, the bottoms are mounted.
	Wells are installed in their places, leveled. A layer of crushed granite or washed gravel with a fraction of 20-40 mm, 10 cm thick is poured into the trenches. The crushed stone layer is compacted, the necessary slopes are created.
	The necessary sections of drainage pipes are cut off, which are completed with plugs (if necessary). In most cases, drain-beams are made from pipes with a diameter of 110 mm, and collectors - 160 mm. Pipes are laid in trenches and connected to well couplings and fittings. Their depth and slopes are checked.
	A 20 cm layer of crushed stone or washed gravel is poured over the drains. After tamping, the crushed stone layer is covered with geotextiles previously attached to the walls of the trenches or from above.
	The drainage system is checked for operability. To do this, in various places where drains are laid, a large amount of water is poured into the trenches. Its absorption into the crushed stone layer and flow through the rotary, collector wells and getting into the main catchment well are controlled.
	A layer of sand is poured over the geotextile, at least 20 cm thick. The sand is compacted, and on top of it, the trenches are covered with fertile soil - 15-20 cm.
	Covers are put on the wells.

Even if the deep drainage of the site was done without a project, it is still necessary to draw up, on which to indicate the location of the drains and the depth of their occurrence. This will help in the future when carrying out any excavation work to leave the system intact. If the relief allows, then the catchment wells may not be arranged, and the water collected by drains is immediately sent to sewers, reservoirs or a collective storm sewer system. Any of these steps must be coordinated with the neighbors and the administration of the villages. But the well is still desirable, if only to control the GWL and its seasonal fluctuations.

The collector well for collecting groundwater can be made overflow. When the water level in such wells becomes higher than the overflow pipe, part of the water flows through the sewer pipe into another storage well. Such a system allows you to get clean water in the storage well, since all the dirt, silt and debris settles in the collector overflow well.

When well-known thinkers, called great, whose statements are constantly quoted and cited as examples, put their thoughts on paper, they probably did not even suspect that they were writing about deep drainage. Here are some examples:

• The collective image of the thinker, which is known to most people, as Kozma Prutkov said: "Look at the root!". Great phrase talking about deep drainage! If the owner wishes to grow garden trees on his site, then he simply must know where the groundwater lies, since their excess in the area of ​​\u200b\u200bthe root system has a bad effect on most plants.
• A very famous thinker and “generator of wisdom” Oscar Wilde also said, without knowing it, about deep drainage: “The greatest vice in a person is superficiality. Everything that happens in our life has its own deep meaning.
• Stanisław Jerzy Lec said the following about depth: “A swamp sometimes gives the impression of depth.” As well as possible, this phrase fits the drainage, since without it the site may well turn into a swamp.

You can cite many more quotes from great people and connect them with drainage, but we will not distract the readers of our portal from the main idea. For the safety of houses and the comfort of their inhabitants, the creation of ideal conditions for the growth of the necessary plants, the arrangement of a cozy landscape, drainage is definitely needed.

Conclusion

It should be noted that residents of most regions of Russia are unspeakably lucky if the issue of drainage is raised. An abundance of water, especially fresh water, is much better than its lack. Residents of arid and desert regions, after reading such an article, would sigh and say: “We would have your problems!” Therefore, we simply must consider ourselves lucky that we live in a country that does not lack fresh water.

As we have already noted, you can always “negotiate” with water using the drainage system. Modern market abundance offers just a gigantic range of various components, allowing you to create a system of any complexity. But in this matter one must be very selective and careful, since the excessive complexity of any system reduces its reliability. Therefore, we again and again recommend ordering a drainage project from specialists. And the independent implementation of the drainage of the site is quite within the power of any good owner, and we hope that our article will help in some way.

Drainage systems in summer cottages and house adjoining areas are often designed "by eye". This is not eaten properly and often leads to flooding and other problems. In order to make the drainage system correctly, it is necessary to be guided by the requirements of regulatory documents.

The basic document is SP 104.13330.2012 - this is an updated version of SNiP 2.06.15-85 "Engineering protection of the territory from flooding and flooding". Unfortunately, it contains little useful information for drainage systems used to protect low-rise buildings.

There is another document - "Guidelines for the design of drainage of buildings and structures" from the Moscow Committee for Architecture, published in 2000 (hereinafter referred to as the "Guidelines"). It contains a lot of useful information, but, like any other piece of legislation, the manual is difficult to read and redundant in places. Therefore, the site brings to your attention a summary, which outlines all the most important things from this document.

When is it permissible to arrange an open drainage system?

According to SNIP, an open drainage system of horizontal ditches can be used to drain territories with one and two-story buildings of low density, as well as to protect roads and other communications from flooding (p. 5.25). At the same time, concrete or reinforced concrete slabs or rockfill should be used to strengthen the slopes of the channels.

Obviously, this item is related to the general drainage systems of settlements or microdistricts. With regard to a specific private house on its own land plot, the creation of an open drainage system cannot be considered appropriate, since the ditch on the site takes up space and poses a potential hazard.

What materials can be used as a filter and filter bed in closed drainage systems?

As a filter and filter dressing in drainage systems, you can use:

• sand and gravel mixture;
• slag;
• expanded clay;
• polymeric materials;
• Other materials.

What pipes can be used to create drainage systems?

According to SNIP, to create drainage systems it is allowed to use:

• ceramic pipes;
• polymer pipes;
• concrete, asbestos-cement, reinforced concrete pipes and pipe filters made of porous cement can be used in soils and water that are non-aggressive to concrete;

How to determine the maximum depth of pipes in closed drainage systems?

The depth of pipes in closed drainage systems depends on their material and diameter. Data on the maximum depth of laying pipes are presented in the table.

How to determine the depth of porous concrete pipe filters?

The maximum laying depth of pipe filters made of porous concrete is determined in accordance with VSN 13-77 "Drainage pipes made of large-pore filtration concrete on dense aggregates."

How to determine the size of the hole in the drainage pipes and the distance between them?

The size of the holes in the drainage pipes and the distance between them is determined by calculation.

How to determine the thickness of the filter around the pipes of the drainage system?

The filter around the pipes of the drainage system should be in the form of sand and gravel fill or wraps or polymeric permeable materials. The thickness of the filter and the composition of the coating is determined by calculation in accordance with the requirements of SNiP 2.06.14-85. "PROTECTION OF MINING WORKINGS FROM UNDERGROUND AND SURFACE WATER".

Can drainage water be discharged into storm sewers?

SNiP allows the discharge of drainage water into storm sewers, provided that the storm sewer is designed for such a load. At the same time, the backwater of the drainage system to the point of discharge into the storm sewer is not allowed.

How to determine the maximum distance between the manholes of the drainage system?

The maximum distance between the wells of the drainage system in straight sections is 50 meters. In addition, wells should be located at the points of turns, changes in angles and intersections of drainage pipes.

What should the manhole of the drainage system be made of?

According to SNiP, manholes must be prefabricated from reinforced concrete rings. They must be equipped with settling tanks with reinforced concrete bottom. Settling tank depth - not less than 50 cm

What data is needed to create a drainage system project?

To design a drainage system, you need:

• technical opinion on the hydrogeological conditions of construction (in everyday life "hydrogeology");
• plan of the territory with existing and planned buildings and structures. The scale of the plan is not less than 1:500;
• plan with floor marks in the basements and undergrounds of buildings;
• developments, plans and sections of the foundations of all buildings located on the territory;
• plans and profile sections of underground utilities;

What should a hydrogeological report include?

The hydrogeological conclusion consists of several sections:

The section "Characteristics of groundwater" includes the following information:

• groundwater sources;
• reasons for the formation of groundwater;
• groundwater regime;
• mark of the estimated level of groundwater;
• mark of the established level of groundwater;
• the height of the zone of capillary moistening of the soil (if dampness in the basement is unacceptable);
• results of chemical analysis and a conclusion on the aggressiveness of groundwater in relation to building structures.

The geological and lithological section includes general information about the land plot.

Soil characteristics include:

• geological sections and columns of soils from boreholes;
• bearing capacity of soils;
• granulometric composition of sandy soils;
• filtration coefficient of sandy and sandy soils;
• coefficients of water loss and porosity;
• angles of natural repose of soils.

Is foundation waterproofing necessary if there is a drainage system?

The “Guideline” of the Moskomproekt unambiguously requires the use of coating or paint waterproofing of vertical wall surfaces in contact with the ground, regardless of the presence of a drainage system.

Are there other ways to protect buildings from flooding and flooding areas (besides creating drainage systems)?

Such methods exist. The Moskoproekt Guidelines for Designing Drainage Systems also recommends:

• soil compaction during the construction of pits and trenches;
• the use of closed outlet drainage systems that collect water from the roofs of buildings;
• the use of open drainage trays with open outlets of drainage systems. The size of the trays is not less than 15*15 cm, the longitudinal slope is not less than 1%;
• blind area around the perimeter of buildings. The width of the blind area is at least 1 m, the slope away from the building is at least 2%;
• sealing of all openings located in the outer walls and foundations with the conclusions of engineering systems. Simply put, if you run a sewer pipe through a foundation or wall, the holes must be sealed;
• creation of a system of surface runoff from the territory.

For the implementation of wall drainage projects, it is necessary to focus on the recommendations of the Moscow Architecture Committee of 2000 (document "Guidelines for the design of drainage of buildings and structures").

Wall drainage is used to protect basements and underfloors of buildings from groundwater, which are laid in clay and loamy soils.

Wall "preventive" drainages must also be arranged in the absence of groundwater in the area of ​​​​basements and undergrounds, arranged in clay and loamy soils.

With a layered structure of the aquifer, wall or ring drainage should be arranged to protect the basements and underfloors of buildings, depending on local conditions.

If individual parts of the building are located in areas with different geological conditions, both ring and wall drainage can be used in these areas.

Wall drainage is laid along the contour of the building from the outside. The distance between the drainage and the building wall is determined by the width of the building foundations and the location of the drainage manholes.

Wall drainage, as a rule, should be laid at elevations not lower than the sole of the strip foundation or the base of the foundation slab.

With a large depth of foundations from the level of the basement floor, wall drainage can be laid above the base of the foundations, provided that measures are taken to prevent drainage from subsidence.

Wall drainage routes are determined by reference to the protected structure, as a rule, directly along the contour of the foundation of the protected building.

The depth of the wall and associated drainages is determined in accordance with the depth of the protected structures and, if possible, should not be less than the depth of soil freezing.

The device of wall drainage must be performed using modern polymeric filter materials. As a rule, in modern conditions, polymer drainage pipes (PVC or HDPE) are used in a geotextile filter.
Longitudinal slopes of wall drainage are recommended to be taken at least 0.002 for clay soils and 0.003 for sandy soils. The greatest drainage slopes should be determined based on the maximum allowable water flow rate in the pipes - 1.0 m / s.

Inspection wells should be installed in places where the route turns and changes in slopes, on drops, as well as between these points at large distances.

On straight drainage sections, the normal distance between manholes is 40 m.

The greatest distance between drainage manholes is 50 m.

Manholes are not required at the drainage bends at the ledges of the buildings and at the chambers on the channels, provided that the distance from the turn to the nearest manhole is not more than 20 m.

In the case when the drainage makes several turns in the area between the manholes, the manholes are installed through one turn.

Water is discharged from drains into drains, reservoirs and ravines.

The connection of drains to drains, as a rule, should be carried out above the drain. In the case of connecting a drain below the sheath of the drainpipe, a check valve must be provided at the drain outlet. It is not recommended to connect drainage to drains below the water level in the latter with a period of excess 3 times a year.

When released into a reservoir, drainage should be laid above the water level in the reservoir during a flood. With a short-term increase in the horizon of the reservoir, drainage, if necessary, can be laid below the flood horizon, provided that the drainage outlet is equipped with a check valve. The wellhead section of the drainage outlet into the reservoir should be buried below the water horizon to the thickness of the ice cover with the installation of a drop well.

If it is not possible to drain water from the drainage by gravity, it is necessary to provide a pumping station (installation) for pumping drainage water, operating in automatic mode.

Drainage sprinkling, in accordance with the composition of the drained soils, is arranged as single-layer or two-layer.

For the inner layer of drainage sprinkles, gravel or crushed stone is used. Sands are used for the outer layer of sprinkling.

Drainage fills can have a rectangular or trapezoidal shape in cross section. The thickness of one layer of drainage sprinkling should be at least 15 cm.

In our design organization you can order a wall drainage project. This page provides detailed information on the requirements for the installation and design of wall drainage (plans, profiles, laying conditions).

THE GOVERNMENT OF MOSCOW
MOSCOWARCHITECTURE

MANAGEMENT
for the design of drainage of buildings and structures

1. DEVELOPED by OJSC “Mosproekt” (engineer Kiskin L.K., Chernyshev E.N., Kovylyaev V.M.).

2. Prepared for publication by the Department of Advanced Design and Standards of the Moscow Committee for Architecture (Eng. Ionin V.A., Schipanov Yu.B.).

3. APPROVED AND PUT INTO EFFECT by the indication of the Moscow Architecture Committee of November 20, 2000 N 48

Introduction

Introduction

Until now, design organizations that design drainage systems (hereinafter referred to as drains) in Moscow are guided by the “Temporary guidelines for the design of drainage in Moscow (NM-15-69)”, developed in 1969 by “Mosproekt-1” and "Mosinzhproekt".

During the practical use of the "Temporary Directives", new drainage designs have appeared based on the use of modern materials, both positive and negative experience in the design and construction of drainage has been accumulated, which necessitates the development of a new regulatory document.

Application area

The "Guide" is intended for use in the design and construction of drainage of buildings, structures and underground utility channels located in residential areas, as well as for stand-alone buildings and structures.

The ”Guidelines” do not apply to the design of shallow road drainages, transport and other special-purpose structures, as well as to temporary dewatering during construction work.

a common part

To protect the buried parts of buildings (basements, technical undergrounds, pits, etc.), intra-quarter collectors, communication channels from flooding with groundwater, drainage should be provided. Drainage structures and waterproofing of the underground parts of buildings and structures should be carried out in accordance with SNiP 2.06.15-85, SNiP 2.02.01-83*, MGSN 2.07-97, “Recommendations for the design of waterproofing of underground parts of buildings and structures”, developed by TsNIIPpromzdanii in 1996, and the requirements of this “Manual”.

Drainage design should be carried out on the basis of specific data on the hydrogeological conditions of the facility construction site, the degree of groundwater aggressiveness to building structures, space-planning and design solutions for protected buildings and structures, as well as the functional purpose of these premises.

Anti-capillary waterproofing in the walls and coating or painting insulation of the vertical surfaces of the walls in contact with the ground must be provided in all cases, regardless of the drainage arrangement.

The device of drainages is obligatory in cases of location:

basement floors, technical undergrounds, intra-quarter collectors, communication channels, etc. below the calculated groundwater level or if the excess of floors above the calculated groundwater level is less than 50 cm;

floors of operated basements, intra-quarter collectors, communication channels in clay and loamy soils, regardless of the presence of groundwater;

basement floors located in the zone of capillary moisture, when dampness is not allowed in the basement;

floors of technical undergrounds in clay and loamy soils when they are buried more than 1.3 m from the planning surface of the earth, regardless of the presence of groundwater;

floors of technical subfields in clay and loamy soils when they are buried less than 1.3 m from the planning surface of the earth when the floor is located on the foundation slab, as well as in cases where sand lenses approach the building from the upland side or a thalweg is located from the upland side of the building.

In order to exclude watering of the soils of the territories and the flow of water to buildings and structures, in addition to drainage, it is necessary to provide for:

normative soil compaction when backfilling pits and trenches;

as a rule, closed outlets of drains from the roof of buildings;

drainage open trays with a section of 15x15 cm with a longitudinal slope of 1% with open outlets of the drain;

installation of a blind area for buildings 100 cm wide with an active transverse slope from buildings of 2% to roads or trays;

hermetic sealing of openings in external walls and foundations at the inlets and outlets of engineering networks;

organized surface runoff from the territory of the facility being designed, which does not impair the removal of rain and melt water from the adjacent territory.

In cases where, due to the low elevations of the existing surface of the earth, it is not possible to ensure the drainage of surface water or achieve the required lowering of groundwater, the area should be backfilled to the required elevations. If gravity drainage of drainage waters from individual buildings and structures or a group of buildings is not possible, provision should be made for the installation of pumping stations for pumping drainage waters.

The design of drainages of new facilities should be carried out taking into account existing or previously designed drainages of adjacent territories.

With a general decrease in the level of groundwater in the territory of the microdistrict, the marks of the lowered level of groundwater should be assigned 0.5 m below the floors of basements, technical undergrounds, communication channels and other structures. In case of impossibility or inexpediency of a general lowering of the groundwater level, local drainage should be provided for individual buildings and structures (or groups of buildings).

Local drainage, as a rule, should be arranged in cases of significant deepening of the underground floors of individual buildings when gravity removal of drainage water is impossible.

Types of drains

Depending on the location of the drainage in relation to the aquiclude, the drainages can be of a perfect or imperfect type.

Drainage of the perfect type is laid on the aquiclude. Groundwater enters the drainage from above and from the sides. In accordance with these conditions, a drainage of a perfect type must have a draining coating on top and sides (see Fig. 1).

Drainage of an imperfect type is laid above the aquiclude. Groundwater enters the drains from all sides, so the drainage sprinkling must be closed on all sides (see Fig. 2).

Initial data for drainage design

To draw up a drainage project, the following data and materials are required:

technical opinion on the hydrogeological conditions of construction;

a plan of the territory on a scale of 1:500 with existing and planned buildings and underground structures;

relief organization project;

plans and marks of floors of basements and subfloors of buildings;

plans, sections and developments of building foundations;

plans, longitudinal profiles and sections of underground channels.

In the technical report on the hydrogeological conditions of construction, the characteristics of groundwater, the geological and lithological structure of the site and the physical and mechanical properties of soils should be given.

In the groundwater characteristics section, the following should be indicated:

reasons for the formation and sources of groundwater supply;

groundwater regime and marks of the appeared, established and calculated levels of groundwater, and, if necessary, the height of the zone of capillary moistening of the soil;

chemical analysis data and a conclusion on the aggressiveness of groundwater in relation to concrete and mortar.

The geological and lithological section provides a general description of the structure of the site.

In the characteristics of the physical and mechanical properties of soils, the following should be indicated:

granulometric composition of sandy soils;

filtration coefficients of sandy soils and sandy loams;

porosity and water loss coefficients;

angle of repose and soil bearing capacity.

The conclusion should be accompanied by the main geological sections and "columns" of soils from boreholes, necessary for compiling geological sections along drainage routes.

If necessary, in complex hydrogeological conditions for drainage projects for blocks and microdistricts, a map of hydroisogypsum and a map of soil distribution should be attached to the technical report.

In the case of special requirements for the drainage device, caused by the specific operating conditions of the protected premises and structures, these requirements must be stated by the customer as additional source materials for the design of drainage.

General conditions for choosing a drainage system

The drainage system is selected depending on the nature of the protected object and hydrogeological conditions.

When designing new quarters and microdistricts in areas with a high level of groundwater, a general drainage scheme should be developed.

The drainage scheme includes drainage systems that provide a general decrease in the level of groundwater in the territory of a quarter (microdistrict), and local drainages to protect individual structures from flooding by groundwater.

Drainages that provide a general lowering of the groundwater level include drainages:

head or coastal;

systematic.

Local drainages include drainages:

annular;

wall-mounted;

reservoir.

Local drainage also includes drainage designed to protect individual structures:

drainage of underground channels;

pit drainage;

road drainage;

drainage of filled rivers, streams, ravines and ravines;

slope and wall drainage;

drainage of underground parts of existing buildings.

Under favorable conditions (in sandy soils, as well as in sandy interlayers with a large area of ​​​​their distribution), local drainage can simultaneously contribute to a general decrease in the level of groundwater.

In areas where groundwater occurs in sandy soils, drainage systems should be used to ensure a general decrease in the level of groundwater.

In this case, local drainages should be used to protect certain especially buried structures from flooding by groundwater.

In areas where groundwater occurs in clayey, loamy and other soils with low water loss, it is necessary to arrange local drainage.

Local “preventive” drainages should also be arranged in the absence of observed groundwater to protect underground structures located in clay and loamy soils.

In areas with a layered structure of the aquifer, both general drainage systems and local drainage should be arranged.

General drainage systems should be arranged to drain flooded sand layers through which water enters the drained area. In this system, individual local drainages can also be used, in which the radius of the depression curve captures a significant area of ​​the territory. Local drainage must be arranged for underground structures laid in areas where the aquifer is not completely drained by the general drainage system, as well as in places where perched water may appear.

In built-up areas, during the construction of individual buildings and structures that need protection from groundwater flooding, local drainage should be arranged. When designing and constructing these drains, consideration must be given to their impact on adjacent existing structures.

head drainage

To drain the territories flooded by the flow of groundwater with a supply area located outside this territory, head drainage should be arranged (see Fig. 3).

Head drainage should be laid along the upper, in relation to the underground flow, boundary of the drained area. The drainage route is assigned taking into account the location of the building and is carried out, if possible, in places with higher elevations of the aquiclude.

The head drainage should, as a rule, cross the groundwater flow along its entire width.

If the length of the head drainage is less than the width of the underground flow, additional drains should be installed along the lateral boundaries of the drained area in order to intercept groundwater entering from the side.

When the aquiclude is shallow, the head drainage should be laid on the surface of the aquiclude (with some penetration into it) in order to completely intercept groundwater, as a drainage of a perfect type.

In cases where it is not possible to lay drainage on the aquiclude, and according to the conditions of drainage, it is required to completely intercept the flow of groundwater, a screen from a waterproof sheet pile is arranged below the drainage, which must be lowered below the aquiclude marks.

When the aquiclude is deep, the head drainage is laid above the aquiclude, as an imperfect type of drainage. In this case, it is necessary to calculate the depression curve. If the device of one line of the main drainage does not achieve a decrease in the level of groundwater to the specified levels, a second drainage line should be laid parallel to the head drainage. The distance between the drains is determined by calculation.

If the part of the aquifer located above the drainage consists of sandy soils with a filtration coefficient of less than 5 m/day, the lower part of the drainage trench should be backfilled with sand with a filtration coefficient of at least 5 m/day (see Fig. 4).

The height of backfilling with sand is 0.6-0.7H, where: H is the height from the bottom of the drainage trench to the unreduced calculated groundwater level.

With a layered structure of a part of the aquifer located above the drainage, with alternating layers of sand and loam, the backfilling of the drainage trench with sand with a filtration coefficient of at least 5 m / day should be carried out 30 cm above the unlowered calculated groundwater level.

Backfilling with sand can be carried out over the entire width of the trench with a vertical or inclined prism, at least 30 cm thick. water).

If the head drainage is laid in the thickness of relatively weakly permeable soils underlain by well permeable soils, a combined drainage should be arranged, consisting of a horizontal drain and vertical self-flowing wells (see Fig. 5).

Vertical wells must communicate with their base with permeable soils of the aquifer, and the upper part with the inner layer of horizontal drain sprinkling.

To drain coastal areas flooded due to the backwater of the water horizon in rivers and reservoirs, coastal drainage should be arranged (see Fig. 6), where the designations are: MG - low-water horizon of the reservoir, GWL - horizon of backed waters of the reservoir.

Coastal drainage is laid parallel to the shore of the reservoir and is laid below the normally supported horizon (NPH) of the reservoir by a value determined by the calculation.

If necessary, head and bank drainage can be used in combination with other drainage systems.

Systematic drainage

In areas where groundwater does not have a clearly defined flow direction, and the aquifer is composed of sandy soils or has a layered structure with open sandy interlayers, systematic drainage should be arranged (see Fig. 7).

The distance between the drainage drains of systematic drainage and the depth of their laying are determined by calculation.

In urban areas, systematic drainage can be arranged in combination with local drainages. In this case, when designing individual drains, one should consider the possibility of their simultaneous use as a local drainage protecting individual structures and as elements of a systematic drainage providing a general decrease in the groundwater level in the drained area.

When laying drains of systematic drainage in the thickness of soil with low water permeability, underlain by well-permeable soils, combined drainage should be used, consisting of horizontal drains with vertical, self-flowing wells (see Fig. 5).

In territories flooded by the flow of groundwater, the supply area of ​​\u200b\u200bwhich also captures the drained territory, head and systematic drainage should be used together.

ring drainage

To protect basements and subfloors of detached buildings or a group of buildings from flooding by groundwater, when they are laid in water-bearing sandy soils, circular drainages should be arranged (see Fig. 8).

Circular drainages should also be arranged to protect especially ruined basements in new quarters and microdistricts with an insufficient depth of lowering the groundwater level by the general drainage system of the territory.
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