Surface drainage systems. Surface drainage

Drainage systems are designed to reduce the degree of waterlogging of a site in the event of unfavorable hydrogeological conditions of the area in which it is located.

Linear drainage systems are a system of canals geographically distributed throughout a site for collecting water from its surface.

Is it necessary to install drainage in a garden or summer cottage?

Surface site drainage systems are designed to quick removal water from the soil surface. This way it is possible to avoid waterlogging and the removal of the fertile soil layer by streams of rain or melt water if the site is located on a slope.

To determine whether the construction of additional drainage hydraulic structures is required on the site, it is necessary to analyze the specific meteorological and hydrogeological conditions of the area, the properties of the soil on the site and its topography.

Over-wetting of the area is likely if:

the site is located on a slope or in a lowland;
the soil on the site is clayey or the clayey waterproof layer lies not far from the surface;
There is a pond next to the site;
the site is located in a flood zone;
close to the surface groundwater;
The site is limited by deep foundations.

What are the dangers of overwatering an area?

Installing drainage on the site

Waterlogging of the soil and underlying layers leads to their general instability. They become mobile and cease to be a reliable support for garden structures, such as paths, causing their gradual destruction.

The foundations of the house and outbuildings, causing, despite the presence of waterproofing, Negative consequences– mold and rot, water in the basement and inspection hole garage.

Puddles that appear here and there on the site, almost never drying out, “steal” precious usable space, creating discomfort for people and agrotechnical conditions incompatible with life cultivated plants. In winter, waterlogged soils freeze to great depths, which cannot withstand root system trees and they die.

Proper site drainage from groundwater: installation of various types of systems

Technologies for surface drainage of dacha plots

A drainage system is constructed to promptly remove excess water from the site. There are two types of drainage systems - linear, when they are created geographically over the area of the site, and point, arranged in places where wastewater enters, for example, at drains drainpipes.

A linear drainage system is structurally a network of channels made of gutters, closed at the top with gratings, or special pipes. Gutters are placed at a slope for natural drainage. To collect sand and soil particles carried away with water and prevent clogging of the channels, flow-through settling filters are built into the threads of the gutters.

Such a filter is a container with a box inserted inside, which is periodically removed and cleaned of sludge.

Drainage lines from gutters covered with gratings are made either in places with a fixed soil layer (lawns) or in places with a hard surface (paths).

For loose cultivated soil, this is done by deepening the drainage system from perforated pipes to a depth of at least 70 cm, below the root system of the plants.

Design and installation of a rainwater drainage system

Installing a drainage system will save you from waterlogging

The need for the installation of point water intakes exists in any case, at least in the form of containers under the drain pipes with subsequent use of water for irrigation. If the site is located in the zone high humidity, then you can’t do without a linear system of drainage pipes.

They start by drawing the diagram of the planned system on paper, calculating required quantity gutters and drainage pipes, parts for their distribution and joining, as well as the number of settling tanks and plugs. Typically, drainage lines are located along the longer side of the site with slopes of half a degree.

A trench with recesses for settling tanks is dug under the drainage line. The depth of the trench is determined by the height of the concrete bed for the gutters, the height of the gutters themselves, the thickness of the grating, plus half a centimeter to the surface.

After laying the gutters from bottom to top along the twine on fresh concrete, the gaps between the edges of the trench and gutters are also concreted. The water intake holes are covered with gratings. The line ends with a settling tank with a pipe in the direction of water drainage.

Doing drainage correctly

Pipes (drains) are laid with a slope in a trench with a layer of crushed stone at the bottom for filtration. The pipes themselves must be wrapped in a special permeable fabric to prevent clogging of the drain holes.

From above, the trench is filled successively with layers of gravel, sand and, finally, excavated soil.

Collection and disposal of drainage water on a land plot

Surface drainage removes natural rain and melt water. Therefore additional treatment facilities, similar to sewer ones, are not required in this case.

It is not advisable to connect the output of such drainage to the system autonomous sewerage, which will be overloaded, and the output will end up with unsettled wastewater.

Surface water that enters the drainage system can be directly discharged into ravines or reservoirs. If there is no direct access to them, the drainage system is completed with a sufficiently capacious drainage well.

And from it water is pumped through a separate pipeline to appropriate place where it is impossible to harm nature or neighboring areas.

In suburban and summer cottage areas there is often excess moisture, which negatively affects the harvest and the condition of the foundation of the house. To combat this phenomenon, surface drainage works well.

Linear surface drainage

The linear surface drainage device involves laying long gutters covered with gratings on top. Gutters are laid along paths, along the contours of areas and in other places where water usually accumulates.

The linear system works on a simple principle - water collects in gutters, flows into them under a created slope and ends up in a collector well. Gutters are made from different materials. The most popular are gutters made of polymer concrete, concrete and plastic.

Note! A linear surface drainage system prevents flooding of a home's foundation by collecting water from the roof and surrounding areas and discharging it to the drain.

If it is necessary to arrange drainage around the house, HDPE pipes with a perforated surface can be used for this purpose. You can do it another way: take sewer pipes and many holes are drilled into them using a hammer drill or drill. They must be made along the entire length of the pipe in 3 rows.

At a distance of half a meter from the house, ditches are dug along the perimeter of the foundation, and perforated pipes are laid in them. Trenches are dug to such a depth that the sewer pipes are completely hidden in the ground.
Using a shovel, all internal surfaces of the ditch are leveled.
The bottom of the trench is covered with a layer of a mixture of gravel and sand.
The pipes are laid in the prepared ditch at a certain angle and taken out beyond the boundary of the site. Pipe openings must be fully accessible. There is a slope in the trenches on opposite sides, which facilitates the rapid flow of rainwater into the pipes. With the help of such a linear drainage system around the house, you can avoid the destruction of the foundation from water exposure.

Point drainage is used for local collection of precipitation in the form of rain. They are installed in many places, which include the space near doors, gutters that are installed on the roof to collect water from the roof, under watering taps, emerging from the niches of the house, at the entrance and parking lot, as well as at other points where moisture often accumulates and puddles form. Concrete wells are constructed for point drainage, with decorative gratings installed on top.

There is an option with pumping out water. To avoid clogging of pipes, sand traps are provided in the system. In addition to the sand trap, the drainage system includes stormwater inlets, ladders, drainage systems and storm flaps.

Note! Point drainage system correct device can go well with linear collection and water drainage.

What elements are included:

The storm water inlet is a container rectangular shape. It is made of polymer concrete or plastic and is equipped with outlets that have access to the water drainage network. Such a network, for example, could be storm drain. To make storm water inlets easier to maintain, they are equipped with special baskets into which large fractions of waste are collected. In practice, storm water inlets with water seals are also used. The presence of siphons does not allow it to spread through the air near the house unpleasant odors. The rainwater inlet can be increased in height - to do this, one element must be installed on another.
Drain ladders have the form of a container, equipped with a decorative protective grille on top. This element is connected to a surface linear drainage or storm sewer system. The purpose of the drain is to locally collect and drain water from paths, developed areas and other vulnerable places.
The storm flap is protective device drainage structure. This element prevents water from flowing in the opposite direction.

Detailed installation instructions are below:

Site drainage

The natural drainage system may not be enough if the site area is located in a wetland or low-lying area. Earth in early spring after the snow melts, it is saturated with water, which stands in place for a long time, while the sprouted plants begin to rot and die. As a result field work go off schedule and the yield of the plot does not reach the level that was planned.

The area of the plot is divided into equal plots. Narrow ditches 0.5 m deep are dug. The ditches are arranged at a certain slope so that the water flows away and does not stand still. In order to fully utilize the entire area of the site, after draining the water in the right places, the trenches are filled with branches and sprinkled with a mixture of soil and manure on top. On temporary additional areas You can grow crops for which dampness is the norm. In the fall, after harvesting, the drainage trenches are restored to their original form - the layer of temporary soil is removed.
Surface storm-type drainage is arranged to prevent washout fertile soil from the site during heavy rains or precipitation falling for several days in a row. Drainage trenches are arranged with a slope for the subsequent removal of water from them. The grooves are sealed with concrete, and plastic or other trays are placed in them. It is possible to have trenches with support boards that rest against the walls of the trenches and are held in a vertical position by transverse struts. Paths are made on top of such grooves, and the trenches themselves are covered with removable gratings.
If the site is located in the middle of a large slope, there is a possibility that short-term heavy rains can wash away a layer of fertile soil. In this case, drainage drainage is required, the trenches of which will be arranged in such a way that the runoff will be collected and the water will be drained along inclined surface, but outside the site. It is necessary to dig a storm trench across the slope, which will become a barrier to the flow and drain water along the edges usable area. Such a ditch must be constantly open. It can be turned into a ravine by sowing it with reeds or other similar plants, but it is better to strengthen the ditch with concrete, because such drainage structures quickly lose their original appearance, are washed away and destroyed.

Site drainage option

If the soil of the site consists predominantly of clay and loam, excess moisture can be eliminated using surface drainage, which involves installing a network of trenches across the entire usable area.

First, a plan is drawn on paper, onto which a network of ditches located throughout the site and a drainage well are drawn, where the collected water will be drained. In order for the drainage to work properly, the trenches are given a slope towards the water receiving object. If the site is on a slope, the direction of flow is selected based on the given direction. If the ground surface is flat, the slope is created artificially. The number of trenches depends on the degree of soil moisture. The depth of the ditches should be approximately 0.5 m, the width will increase as you approach the water intake.
Once the drainage system is ready, it is checked for drainage quality. To do this, water is released from a hose into the ditches and the flow rate is monitored. If there are areas with stagnant water, the slope in these places increases.
If the test was successful, you need to start decorating the trenches - bare ditches look unattractive. To do this, a layer is poured onto the bottom of the ditches. marble chips or decorative gravel. Plants are planted on the “banks”.

Many have encountered such a common problem as excess moisture on suburban area. Clay soils do not drain water well, and in the spring, when the snow cover melts, they become heaving. Because of this, the foundations of buildings deteriorate and shift, and road surfaces are destroyed. There is an opinion that it is impossible to do site drainage on clay and loamy soils with your own hands. But this is a myth. Of course, it is better to entrust the drainage of the site to a competent and experienced specialist, but this is not always possible. We will try to figure out how to install a drainage system.

What for?

Excess moisture in the countryside is a serious problem. Her first a clear sign- these are puddles that may not go away for several weeks in a row. This problem can cause the slow destruction of houses and other country buildings and the death of plantings. And few people find it comfortable to go to rubber boots or constantly watch puddles.

Excess moisture is an unpleasant phenomenon

Often this problem occurs due to perched water. That's what they call it high level underground (ground) waters.

The easiest way

So, how to make drainage on the site? Some craftsmen who decide to make drainage at their dacha with their own hands simply dig ditches (popularly called “drains”) along the perimeter of the site. This is the simplest, most inexpensive and widespread method for removing excess moisture from the surface. And this sometimes solves the problem.

Unfortunately, if the territory is located below the lateral ones adjacent to it, such drainage arrangement will not help, only raising the general ground level will save it. To do this, you need to bring and add soil and level it. But what if the neighbors decide to raise the level too? Still, it’s better to close this issue once and for all and initially perform drainage efficiently summer cottage with your own hands, so as not to return to this issue again. Therefore, many people prefer to carefully figure out how to drain the area in order to forget about the problem, like a bad dream.

First thing's first - plan!

First of all, having taken up the construction of the drainage system, they draw a diagram of the future drainage. At this stage, it is important not to make a mistake and take into account all the features of your landscape. Each territory is unique. For example, drainage is also necessary, as on absolutely flat ground. Streams of water wash away the fertile layer and unevenly erode the soil. If you make gross miscalculations, you may have the opposite effect and the situation will not only not change, but will even worsen. This can be avoided by studying possible options, installation rules and principles, and then draw your site drainage project.

First, determine what type of drainage system you will use: surface or deep site drainage (pipes will be required for site drainage).

Surface drainage

Doing surface drainage of a site with your own hands is relatively easy. Shallow drainage is arranged when they want to protect first of all country houses, be it a cellar, underground parking or basement. Term shallow is due to the fact that the entire system is in plain sight, on the surface. This system consists of various trays and storm inlets that collect water during rains, downpours and after heavy snowmelt. Surface drainage, in turn, is also divided into two types: linear And spot.

Linear type- this is a chain of trays laid in a certain way. An analogy can be drawn with a canal whose slope is directed towards a well. It is into this that all the water ultimately removed from the trays enters. Similar device Drainage on the site is carried out along paths or open parking areas, along the perimeter of sheds and garages. But most often, as a rule, it is the drainage of the house. We have known such a drainage system on the site since Ancient Egypt. The principle is the same, only the materials are more advanced. Nowadays trays made of reinforced concrete or plastic are used. There is a grill built into the top that covers the gutter. There are also special waste bins built into the system to make cleaning easier.

Spot type is a system of water collectors installed in places where it is necessary locally collect water. Catchments are usually installed under taps and in deep depressions, but primarily under gutters. If this is not done, water from the roof will flow to the ground and then penetrate into the soil, destroying the foundation and underground rooms, if any.

Water collectors are installed in the ground so that they are on the same surface as the general soil level. Pipes are drawn from them to sewer system. The top of the catchment area is covered with a grille, which also serves as protection against debris and can act as decorative element. Drainage basins require cleaning periodically. To do this, you just need to lift the grate and remove the accumulated debris.

Both of these types are often used in pairs for the most efficient drainage system design. The surface type (without pipes) can also include open drainage. In this option, ditches are dug and remain open (in rare cases, they are covered with grates that protect them from large debris). And in order to prevent the walls of the ditch from collapsing and crumbling, they are made at an angle of 30 degrees and laid out with cobblestones or planted ground cover plants. It is even possible to fill it with crushed stone to prevent destruction, but this will reduce its throughput. Even a beginner can do this kind of drainage with his own hands.

Deep drainage

It is better to install such a system on initial stage landscaping, simultaneously with the construction of the house. In this case, it is better to start draining the land by determining the direction of water flows during rainstorms. Having solved this problem, purchase drainage pipes and geotextiles.

The top layout of the pipes should resemble a herringbone pattern.

Previously, drainage pipes ( drains) were made of asbestos cement and ceramics, but in our time they have given way to plastic: HDPE (polyethylene low pressure), LDPE (polyethylene high pressure) and PVC (polyvinyl chloride). They come in single-layer and double-layer, with a diameter of 100-190 mm. Water-permeable holes of up to 3-5 mm are made across the entire surface. To prevent the perforation from becoming clogged and silting, pipes are most often sold already wrapped in geotextile, which performs a filtration function. On clays and loams it is better to have 2-3 layers of fabric for reliability, since the particles in such soil are smaller and clog the system faster than on sandy loam soils. Drains are laid in the soil to a depth of 1.5-6 m, depending on the requirements. The drainage depth is calculated taking into account the groundwater level.

Wells are installed in places where there are sharp turns or connections between several pipes. They are needed for convenient cleaning of the system in case of unexpected blockage and for inspecting the condition of the drainage pipes. Ultimately, the entire chain of inspection wells and pipes should lead to a common collector well (in the lowest place of the land), from where the water is sent by gravity to a drain outside the territory or is forcibly pumped out manually.

In order for the water to flow in the direction you need, you need to lay pipes at a certain angle. Ideally, you need to make the angle as small as possible, since when fast current water siltation occurs earlier.

As a rule, they do slope from 0.5 to 3 cm per meter pipes.

You can set this angle using a level, a water level, or using scrap materials - regular board And building level. In the latter case, the board is laid at the bottom of the trench, and a level is placed on top and measured, and adjusted if necessary.

Now let's figure out how to properly install a drainage ditch. To begin with, we dig trenches (drainage ditches) of the required depth, compact the bottom, and maintain the correct slope (at this stage it can be approximate). Next, pour a 10 cm layer of coarse river sand, spill it and compact it. We carry out the leveling, maintaining the exact slope. Then we lay a layer of geotextile on top with a density not exceeding 200 g per square meter. m. The edges of the fabric should go along the sides of the trench so that they can then be wrapped inside. We pour washed crushed stone onto the geotextile: for clay soils we take a larger fraction (150-250), for sandy loams it can be smaller (up to 150).

Please note: the crushed stone should not be limestone, as it is highly susceptible to erosion and deformation under conditions of temperature changes.

We lay the drainage pipe and gradually fill it with crushed stone in layers and compact it thoroughly. There should be a 10-30 cm layer of crushed stone on top of the drain. We wrap the geotextile inside so that the overlap of the edges is at least 15 cm. Next, pour river sand, and at the very end - fertile soil. The drainage ditch is ready.

Installing a drainage ditch requires a certain investment of time and money, but this work is done once and for all, so it makes sense to do it with the utmost quality.

In order to improve the land area, it is necessary to carry out surface drainage of the site. This is a very important event and is one of the main ones.

Even in cases where the soil does not accumulate liquid, it is still necessary to install drains, ditches and drain the land.

This will protect the building’s foundation from the aggressive effects of groundwater during floods and intense rainfall. But when it comes to areas where there were previously swamps, peat bogs, alumina fields or sand pits, a powerful drainage system is needed.

Specifics of the problem

Before arranging drainage, you need to assess each specific situation and identify the reasons for the appearance of water, and they can be very different:

flooding and prone to flooding;
swampy ground and high percent GW content;
terrain;
close location of rivers and reservoirs;
high groundwater level, etc.

To protect against floods, seasonal or short-term, dams are used, built for several settlements at once.

To solve the problem of waterlogging, the ground level is raised by constructing embankments. In this case, the issue is resolved for several seasons. Therefore, for greater efficiency and reliability, it is necessary to construct a drainage system.

When there is oversaturation with moisture, when there is an underground river or reservoir nearby, as well as during the rainy season and snowmelt, groundwater takes up all free areas. In such a situation, the water will stand until it evaporates.

On soils such as clay and loam, the so-called “overwater” is formed. These soils do not have good permeability and large quantity water, their particles expand, forming a single waterproof layer and the water remains until completely dry.

There are two ways to combat this:

Improve clay soils by making them looser, adding sand and organic fertilizers. This is not difficult to do in small areas.
Drainage of water outside using a dehumidification system.

There is a method of vertical or horizontal soil drainage. Vertical - prevents moisture from escaping into the soil and accumulating near the water-resistant clay layer, and horizontal - does not allow water to accumulate on the surface.

What are the features of drainage communications

Drainage is a network of communications designed to drain groundwater from the soil in order to improve soil quality (which is especially important when creating good conditions for crop production) and the safety of operation of any structures.

In the absence of natural drainage, artificial systems are used. There are two types:

Deep.
Superficial.

They are a complex of water intakes and drainage systems - special trays and ditches. To install deep vertical networks, special pipes with holes are used as drainage systems, installed vertically and passing through aquifers of the soil.

Water is directed to the lower layers of the soil or removed outside the territory. This type drainage requires serious geological and geodetic surveys so that the costs are not in vain. Vertical drainage is not suitable for areas with mixed, heterogeneous soils.

At the heart of the deep horizontal system drainage – the structure of drainage layers, which includes:

perforated pipes for drainage;
gravel fraction 20-40;
geotextiles;
drainage wells assembled;
coarse river sand;
prefabricated reinforced concrete well.

For the drainage system to work satisfactorily, the following conditions must be met:

The calculation of the depth and width of the trench is carried out in such a way that water cannot pass through it. The drainage ditch is filled with material with an optimal filtration coefficient;
the permissible slope of the system must be at least 0.5 cm per 1 m; the bottom of the trench is filled with sand from 150 mm, followed by a separating layer of geotextile with outlets (between sand and crushed stone);
it is necessary to choose the correct diameter drainage pipe, which is laid on gravel, taking into account the specified slopes. Gravel is selected in a fraction of 20-40 mm. This helps retain heat due to the presence of air gaps between the stones, as well as the rapid drainage of water into the pipes;
the finished system is wrapped in a pre-laid filtration layer (geotextile) and covered with coarse-grained washed river sand;
Drainage wells are installed in corners and straight sections (more than 25 meters in length) to monitor and check the system and for its further cleaning.

How to choose a drainage system

With any method of draining the soil, the principle of the drainage system is to remove excess liquid from the site. Pumps are used only in cases of extreme necessity, when it is not possible to drain water by gravity.

The drainage system should be selected based on the following features:

Is there any excess moisture in the area where construction or planting is planned, in what volume, and is it necessary to remove it;
is there a natural slope in the area;
soil composition and throughput;
reasons for excess water in the soil;
Is the area landscaped (tiles, asphalt, lawn);
is there a local sewage system nearby, since this fact will affect the design features of the drainage system.

Most specialists involved in drainage systems are proponents of using combined types drainage

This is the most budget look drainage works, and it is simply aimed at removing excess liquid directly from the soil surface. It is popular for a reason least cost(both physical and material) for arrangement. Most often it is used when large puddles often form and during floods.

As a rule, in most cases, minimal work is sufficient: small trenches that you can dig yourself using primitive mechanisms. Only in special cases dimensional is used construction equipment. Sometimes ditches are equipped with trays for collecting liquid.

The surface drying system consists of the following:

single channels around the perimeter of the site;
bypasses - throughout the entire planned territory;
Trench-furrows are shallow channels located between flower beds or beds.

Devices that drain water away from buildings (roof gutters and gutters) are part of the drainage system. They can be open or closed.

The water collector can be:

street ditches and ravines;
storm sewer collectors;
natural bodies of water.

Surface drainage systems are most often used in land plots, intended for gardening and vegetable gardening. In other cases (for the construction of buildings and structures), more constructive methods are needed.

Point drainage

This drainage method allows you to collect excess water:

near the paths;
under and around watering taps;
under roof gutters;
near the garden fountains.

In this way they supplement linear method drainage And when using this combination, you must first develop a general drainage plan so that the connection to the general storm sewer system is correct.

Biodrainage

The presence of plants on the territory allows for drainage in a natural way. If there are more problem areas, then channels are built there, filled with filter layers: gravel, sand, etc. Plants are planted above these channels that can naturally dry (drain) the soil. If necessary, you can additionally use tubes for drainage.

This method, like others, requires taking into account the characteristics of the soil, layout, and the nearby proximity of buildings and plantings.

Design and installation of surface drainage

The most difficult thing to design is linear system drainage This is a network of channels laid at a shallow angle, running throughout the territory in places with the greatest accumulation of water.

First, they draw up a design for the entire system, where the main thing is the central ditch for general water collection. It ends in some kind of ravine or storm drainage system. During design, all expected flood areas must be taken into account in order to correctly lay channels from these areas to the central trench.

If calculated correctly, water will move well in in the right direction. The slope of the pipes must be at least 0.03, for clay soils - 0.02.

Types of surface drainage:

Open. Such drainage is a network of trenches dug according to a pre-created pattern, where the angle of inclination is 30°, the width is 0.5 m, minimum depth– 0.7 m. These structures are quite light, but not very aesthetic.
Closed. With closed surface drainage, drainage trays (plastic or concrete) are used, which are installed inside the trench and covered with gratings (protection from contamination). The system is protected from soil sliding.

The efficiency of communications is also ensured by an angle of inclination from 0.005 to 0.01.

If the soil is excessively loose, then crushed stone is used for sprinkling, where the coarse fraction is used for the bottom of the ditch, and the fine fraction for the top.

If all technologies are followed, the drainage system will certainly be productive and will allow the site to be used for any planned purposes. And by turning to qualified specialists, you will protect yourself from unpleasant surprises that arise as a result of mistakes and ignorance of the nuances and subtleties of these works.