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Depth of storm drainage. Depth of storm sewage

Livnevka, as it is often called, helps keep the territory clean and does not allow water to wash away the walls and foundations of the structure. But the effective work of such a system depends to a large extent on correct calculations and planning, so it is necessary to know what the depth of the deposit should be storm sewage. This is exactly what this article will be about.

We study norms

All construction and installation work must be carried out in accordance with current regulations, rules and regulations. Such requirements are specified in GOSTs and SNiP. The same applies to the installation of storm sewers. Here acts SNiP 2.04.03-85, which is called "Sewerage. Outdoor facilities and networks. "

In some paragraphs of this document, the recommended depth of the sewage pipes is indicated. According to them laying should be done:

for pipes with a section up to 500 mm not less than 30 cm below the freezing level of the soil;
for pipes with a section more than 500 mm - not less than 50 cm.

But all these points concerning depth of occurrence, have rather advisory character. Their application rests with the conscience of installers and builders. According to SNiP, installation should be carried out based on the experience of operation of sewage systems in each specific region. Generally minimum depth must be at least 70 cm from the surface.

How deep to choose

Most the best option Is to lay pipes storm drainage below the freezing level of the soil. Digging a trench, it is worth knowing this figure, and even add to it the thickness of the sand cushion at the bottom. But in reality, this does not always work.

In some regions of our country, especially those closer to the north, the depth of freezing can reach one and a half or even two meters. Plus, the soil itself, it can be quite stony.

In addition, it is necessary to take into account the requirements for sloping pipes. If you do not comply with it, then the water will not go away, then the efficiency of the storm will noticeably decrease. And in this case, moreover, if the terrain is uneven, the depth of some trenches can reach large values.

Some may ask a question - but you can lay pipes closer to the surface, after all, so often come in the installation of domestic sewage? But in these systems there is a significant difference. It consists in the temperature of the drains.

Note! In domestic sewage, if the house is constantly inhabited by people, the temperature of the drains is always room. Constantly flowing warm water and impurities warm up the pipes themselves and the space around them. As a result, freezing is unlikely.

In the storm sewer there are no warm drains. And the water there is not always. All the winter in the pipes is empty, in addition, the minus temperature. When spring begins, meltwater enters a cold "dungeon". As a result, icing and congestion are formed.

If there is no possibility to deepen the storm sewage system below the depth of freezing of the soil, then it must be insulated. And this issue should be taken very carefully. If the pipes are thermally insulated, then it is not necessary to deepen them deeply into the ground.

Than to insulate storm sewer pipes?

If the decision is made to lay storm sewer pipes above the freezing level of the soil, they must be insulated. To do this, you can use different materials. But here the main thing to remember is that the heater will always be in an aggressive environment.

For heat insulation pipes it is possible to use polyurethane. Today, special constructions are produced from this material, which are easily put on pipes. Such a "shell" reliably protects livnevku from temperature changes.

It is also convenient to use polystyrene foam or expanded polystyrene. From this material already prepared heat insulators are manufactured. It is made of two halves and easily snaps into the pipe.

One of the modern thermal insulators is penoizol. It is poured in a liquid form directly into a ditch with a pipe. After solidification it turns into a good and durable insulation. But for its installation it is necessary to use a special technique, which is not always possible.

But mineral wool and foam polyethylene are not very suitable for insulating pipes in the ground. Even if you make a special box to protect the insulation, it is unlikely to last long enough.

Summarize

If we carry out some results, we can draw the following conclusions:

The depth of laying of storm sewage pipes should be greater than the depth of freezing of the ground, at least 30 centimeters.
If laying at such a depth is impossible, then the livnovke should be insulated. Otherwise, problems may arise in the winter.

The definition of depth is individual and depends on many factors. If the soil and the terrain can allow, it is possible to do everything according to SNiP. Well, if this is not possible, then it is worth insulating the pipes.

Video

This video explains in detail the depth to which the sewage pipe should be buried:

Atmospheric precipitation brings a lot of trouble to residents of country houses, if they do not provide a challenge. The most common problems faced by owners are the erosion and gradual destruction of the foundation, the flooding of the plot, the rotting of the roots of trees and bushes growing in the yard, the formation of a swamp.

To avoid the consequences of torrential rain, you can install a simple storm sewage system, for the arrangement of which does not require much effort and financial costs. Storm sewage is a system consisting of the following elements:

observation wells;
devices intended for the transport of effluents;
sand catchers;
rainwater receivers.

There are two technologies that can be used for storm sewerage: point and linear.

Note! Linear sewer system is more functional. It is able to collect wastewater from large areas, it is used to remove atmospheric precipitation, which drain from the roof, sidewalk.

The first thing that needs to be done when arranging the storm sewage system is to compile the design and calculations of the system. If this stage is missed, you can face a number of troubles in the process of operation. If an inadequate drainage network is built up, the water will stay in the territory, however, in smaller quantities. If you perform too powerful a system, you will have to spend a lot of extra money not only in construction, but also in maintenance.

average amount of precipitation for the area according to meteorological data;
if you plan to use storm sewage to drain melt water, you should consider how powerful the snow cover is;
the area of the territory from which the runoff will be collected;
soil characteristics;
communications, laid underground.

Storm sewerage

When calculating the dimensions, it is necessary to determine the amount of storm sewage, the depth of the deposit, the slope necessary for the high-quality functioning of the system. If you are in doubt, that you will calculate the necessary parameters correctly, seek the advice of a specialist.

Important! Accurate calculation of the size of storm sewage will ensure maximum efficiency of its operation, and also will help to save financial resources at the stage of arrangement.

How to calculate the volume

One of the most important parameters that should be taken into account in the arrangement of storm sewerage in the area a country house Is its volume. The main criterion for the calculation is the average amount of precipitation falling in a particular area. Consider rainwater, snow, hail.

The volume of sewage depends on the size of the collectors and water collectors. Determine the amount of sewerage by a special formula, for which the following values are needed:

number of drains entering the system (approximate figure can be found in the collection of SNiP);
intensity of precipitation;
the area of the area from which the runoff will be collected;
correction factor.

Arrangement of storm sewage in the country house site

All the values obtained are simply multiplied. It is quite easy to calculate these parameters. The only question that may arise is what is the correction factor. This is an indicator, depending on what material is covered by the territory from which the wastewater will be collected. If this area is covered with rubble, the coefficient is 0.4, for areas flooded with concrete - 0.85, for asphalt-covered sites - 0.95 and for roofs-1.

Depth of channel

Another important parameter is the depth of the storm drainage. Trays are laid at a depth characteristic of the region. To find out the depth of storm sewage, you can ask your neighbors or representatives of the construction company. This parameter also depends on the diameter of the pipes that will be laid.

Note! It is impossible to combine rainwater sewerage and drainage system, as they will be very inefficient to operate, which can lead to flooding of the site with precipitation.

Channels of storm sewage

It is desirable that the channels of storm sewage are laid above the groundwater table, but below the freezing level of the ground, and this range from 1.2 to 1.5 meters. Considering that it is necessary to exert a lot of effort and spend a lot of money to perform excavation, the owners decide to reduce the minimum depth of storm drainage. If the diameter of the pipe is 50 mm, the laying should be carried out at a depth of at least 0.3 m, but if the diameter is greater, the pipe is deepened by 0.7 m. When calculating the depth, the nature of the soils on the site is also taken into account.

Slopes of storm sewage

Storm sewage is a non-pressure system for removing atmospheric precipitation. For its effective functioning it is necessary to correctly calculate minimum gradient storm sewage. It is determined taking into account the rate of flow of sewage through the channels and the diameter of the pipe.

If you make too little a corner of the storm sewer, it will not work effectively. A large angle of inclination contributes to the volume, then the effluents will accumulate very quickly in the lower part of the system, without having time to soak up the soil. To not calculate these values yourself, you can use the table, which is located on the pages of the SNIP.

Slopes of storm sewage

If the diameter of the pipes is 200 mm, in order to calculate which slope for storm sewage, a coefficient of 0.007 should be applied.
When installing pipes to the rainwater receivers, they are laid with a slope of 0.02.
Gravel-filled canals responsible for drainage should be laid with a slope of 0.003.
For drainage chutes, the average value of the slope angle is 0.003-0.005.

Correctly calculated basic parameters of storm sewerage are the guarantee of long-term and qualitative functioning of the system for diversion of atmospheric drains.

A technical facility intended to collect and divert rain (thawed) water is called storm sewage. This is one of those important designs of economic and technical purpose, which are among the integral elements of residential, economic, industrial buildings.

An important factor in the construction is the calculation of storm sewage. The construction of the system "blindly", threatens the risks of flooding of landscape areas and the destruction of the soil structure.

The practice of constructing various types of structures shows the application of three types of systems, each of which is distinguished by methods of collecting and removing products of atmospheric precipitation:

Based on open channels and trays (arychnaya).
On the basis of closed wells and pipelines (closed).
Based on the combined solution (mixed).

The first project is implemented in practice by constructing canals that connect the catchments with each other and, ultimately, divert the collected water beyond the intended territory. All these elements of storm sewage have an open communication with the environment. For the construction of such structures, relatively few resources and materials are required.

Storm sewage open type in industrial design. The main elements of the construction are concrete trays, on top of which are laid trellised metal sheets. By the same principle, open schemes of livestock for private housing construction

The scheme of storm sewage closed type should be considered more sophisticated in the design plan. Here erect hidden drainage lines, as well as a system of rainwater receivers - special intermediate storage tanks.

The tapping of collected water is carried out through pipelines laid and buried underground. As a rule, the collected products of atmospheric precipitation are discharged to treatment facilities and further into the water area of natural reservoirs.

The third option is mixed storm sewerage. It is built on the basis of installation components designed for both open and buried systems. The design of mixed storm sewage is based on the rational operation of the system in certain areas of the terrain. Not the least role in deciding on the choice of a combined option is the financial side of its implementation.

Separately, it is necessary to distinguish a rainy (tray) system for collecting and discharging rainwater. This scheme of storm sewage, together with a simple scheme for its manufacture, inherent versatility of operation.

Arychnaya storm sewage has the advantage that, together with the rainwater drainage function, it can act as a supplier of moisture for agricultural plantations. It is also an economical construction option compared to other projects

Thanks to the arychnic design, it is really possible to organize not only a completely effective drainage of atmospheric precipitation products. The same system can be successfully applied as an irrigation structure, for example, for the needs of the household (summer) economy.

What is considered in the calculation

For each private building site (the site being exploited) the design of an individual storm sewage scheme is common. However, decisions that are typical for typical storm-building projects are always taken as a basis.

Typical solutions by default assume access to technical calculations, before the construction of the system begins. Calculations are carried out with an eye on SNiP and taking into account the following factors specific to a specific locality and object:

rainfall rate for the year;
soil properties;
the area of the object;
mass of discharged water;
required drainage area.

In addition to information on the mass of precipitated precipitation, the rest of the information can be obtained through contacting the local geodesy service. A conditional amount of abstracted products of atmospheric precipitation is calculated using the formula where the catchment area and the intensity parameter of these precipitation are taken as the calculated data.

The mathematical form of the formula:

M = (A * 20) * S * k

Respectively:

M - mass of discharged water

A - intensity of atmospheric precipitation within 20 minutes

S - catchment area (for a roof also + 30% of the total area of the building walls)

k is the moisture absorption coefficient of the object material

The roofing coverings (k = 1) are often used as object materials; concrete and asphalt structures (k = 0,9); soil (k = 0,75); crushed stone, gravel (k = 0,45).

System installation features

Collection and removal of atmospheric precipitation from the roof of the building is carried out through external lines of riser pipelines located under the end points of the receiving gutters. In turn, the receiving chutes are mounted along the perimeter of the roof area under the lower edge of the cover.

Collection of rainwater (thawed) water from the roof area is carried out, first of all, by gutters. These structural elements are mounted along the bottom edge of the roof covering and at the lowest point of the slope adjoin the riser. Further along the pipe the water is directed to the rain receiver

On flat roofs, the drain goes directly to the pipe risers. Under this scheme, drain pipelines are usually mounted vertically inside buildings, and their upper flares are projected onto the roof and are integral with the roofing carpet. On flat roofs of private houses, one drainage funnel is allowed.

If the house uses internal risers with an open outlet, their design should provide for the possibility of draining the melt water in the winter time into the sewerage system. The outflow line must be made with a hydraulic seal. Based on the calculated data on the water consumption weight, the diameter of the pipes for the construction of the riser is determined.

Tube selection table for riser:

The preferred material of internal drain pipes is plastic, asbestos cement, cast iron. Tin and plastic pipes are usually used for the installation of an external storm sewage system.

When installing horizontal trunk lines, it is required to withstand a normative slope (not less than 0.005 m and not more than 0.15 m per 1 m of line length).

Storm sewage projects for private housing construction usually involve the use of plastic pipes for the installation of linear lines. This is the most reliable option, but the most economical. However, frequent damage to individual sites nullifies all savings

In cases of maintenance, it is necessary to provide for the installation of audits and cleaning. On the risers of the storm sewer, the audits are mounted within the boundaries of the lower storey of the building.

Livnevka own hands

Owners of private homes are quite capable of building communications to collect and drain rainwater (thawed) water. After completing all the calculations and acquiring the required materials, proceed to action on the arrangement of storm sewage.

The first thing to do is dig trenches for drainage lines in the local area, according to the planned plan. Bring trenches to the points of location of drainage risers (drainpipes). Under the layout of the private economy, the depth of the trench is 300-500 mm.

Performing excavation of trenches, take into account the slope of future pipelines (or trays) in the direction of the central catchment tank. The bottom of the finished trenches is compacted by ramming and covered with a layer of river sand (at least 200 mm high)

At the sites under the drainpipes, digging pits under the rainwater receivers and installing them. These elements of the system are rectangular containers of small volume (5-10 liters).

It is recommended to use ready-made industrial plastic containers or make cast of polymer concrete. Sprinklers, as a rule, are supplemented with baskets-collectors of large rubbish. Natural garbage inevitably falls into the storm sewer system with rainwater flows.

One of the numerous existing structures of rainwater receivers. The material of manufacture is plastic. Optimal choice within the framework of private real estate projects. Such containers, as a rule, are supplemented with baskets-filters for delaying large debris

Proceeding from the chosen technology of storm drainage (open or closed), trenches lay trays or mount a line of polymer pipes. If a simple drainage system is used to drain onto a nearby lawn, it is desirable to provide the risks of possible soil erosion in the drainage areas. Elements of closed installation in the joints are necessarily sealed.

The communications thus assembled must be connected to a common storage reservoir or a centralized network collector. Also, care must be taken to construct sand filter filters immediately before entering the common storage. And do not forget to install inspection wells. Their installation is necessary on sections of highways with a length of more than 10 meters, as well as in the places of the circuit where turns of the drainage line are formed.

The task of collecting collected water

A serious challenge for the owners of suburban real estate is the removal of rainwater collected from the total area of the site. If there are no centralized communications near the house, two options remain for solving this problem:

Collection in a special tank with subsequent use for irrigation;
Discharge of water from the storage tank to the ground or into natural natural areas.

The first option is considered rational provided that there are objects for irrigation on the territory of the house. In this case, a simple adaptation (household pumping station) to select water from the storage tank and then feed it to irrigation areas.

The scheme of tapping of collected rain water into the ground. One of those possible to apply schemes, which are available to the owners of country houses. Efficiency at the tapping speed is low, but taking into account the application in small areas, this scheme is quite suitable

The second option is accompanied by great difficulties. Conclusion in the ground is a long process. How much time will be required for withdrawal depends on the ability of the soil to absorb moisture. At different relief areas, the saturation of the soil with moisture may differ significantly.

In order to divert the product of storm sewage into natural natural zones ("to relief" or "to the landscape"), an additional scheme will have to be implemented. This scheme includes a central water basin and a sewage treatment plant.

The scheme of output "on the relief" or "on the landscape" is accompanied by the complexities of the construction of cleaning modules. Both options require agreement with environmental authorities.
Usually, with the subject of the agreement, the owner of the property (site) has to contact the following organizations:

Department of Natural Supervision.
Fisheries management.
Office of Consumer Supervision.
Basin and water management.
CGMS.

The subject of approval is the "Draft regulations describing the discharge procedure". On the basis of such a project, a permit is issued permitting the discharge of pollution "to the landscape" or "to the relief," and a decision is made to provide the water body.

Discharge of water from storm sewers "onto the relief" or "to the landscape". Such schemes are not regulated in any way by the SNiP documents.

The implementation of such options illegally involves the risk of high fines, and legal discharge requires agreement with the authorities

Rainwater drainage through other networks

Private property projects traditionally include, along with storm sewage, other communication networks. Household sewerage and drainage system are also part of household communications. The principle of their operation differs little from the functioning of a storm shower, in which owners of private houses often see the possibility of using these networks.

Meanwhile, the combination of storm sewerage with a domestic or drainage scheme for drainage is prohibited SNiP. The ban on the combination of different types of sewage is caused by obvious factors. So, under the condition that rainwater is discharged into the domestic sewage system and taking into account the high intensity of atmospheric precipitation, the normal level of sewage is overestimated several times.

Underflooding of working wells leads to the blockage of domestic effluent. Mud sediments, natural garbage rush into the sewage system. As a result, after another shower, the organizers will have to clean up the system.

The combination of stormwater with a drainage line threatens to result in an even more deplorable result. Overflow of drainage due to disturbance of design loads leads to underflooding of the foundation of the building. Frequent flooding disturbs the structure of the ground, which causes the displacement of the foundation blocks, and in the future can lead to the destruction of the building.

Video about different types of storm sewage

Useful videos will expand your horizons about the appointment and installation of storm sewers.

Livnevka in a private house - from project to installation:

Industrial technologies:

The device of storm sewerage, as a rule, is provided during designing of different building objects. Especially, the stages of designing and careful calculation of storm sewage are an integral part of the construction of private houses. A well-designed project livnevki and exact calculations - it is durability of the structure and comfortable environment for its occupants.