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Who rules the ball underworld: factors affecting the distance between sewer wells

Surely you at least once in your life wondered why so many sewer manholes come across on your way. Looking ahead, I will say that this is not someone's whim, but a necessity dictated by technical requirements when laying the sewer system. To clarify these points, I have summarized all the current regulations and will gladly share my knowledge with you. So, let's hit the road.

Everyday educational program

For those who do not like to read for a long time, I inform you that, according to clause 4.14. SNiP 2.04.03-85 on all sewer networks, without exception, wells are provided. The permissible distance between two underground devices depends on the diameter and ranges from 35 to 300 meters.

Those who really want to find out the features of the location of sewer wells should arm themselves with a couple of minutes of patience and read the article to the end.

So, what is hidden under the hatch? Directly below it is a special hydraulic room, called ... yes, yes, a well. Depending on the type, they are designed for a specific type of maintenance work:

1. manhole serves for direct control of complex sections of the sewage system. In the event of clogging, which is inevitable when sewage is removed, both social and industrial, through such wells, repair teams gain access to problem areas;

1. Rotary wells duplicate the functions of observation points, located at points of direct change in the direction of movement of sewage. Turning or bending the sewer pipe increases the likelihood of blockage; this type of underground structures allows to quickly eliminate the problem;
2. Where the landscape creates too much slope, or at the intersection with other engineering and technical underground structures, drop wells are installed;

It would seem that the greater the slope, the faster the drains will leave the pipe. But in fact, an excessive slope, like its complete absence, harms the sewer system - the solid fractions of wastewater, not keeping up with the more liquid ones, accumulate, clogging the pipe lumen.

In the photo - a sewer differential well with the cover removed.

1. Nodal wells unite several pipelines and allow them to be controlled.

Regulatory documentation

Let you not be surprised by the fact that SNiP 2.04.03-85 of the USSR Civil Code for construction, approved back in 1986, still regulates the construction of sewer networks.

In our time, and more specifically, in 2012, the Ministry of Regional Development published the Code of Rules SP 32.13330.2012. In fact, this is a revised edition of SNiP 2.04.03-85, which introduces some additions to the text.

Along with this, there is also SNiP 3.05.04-85, which pays more attention to the laying technology and the materials used.

Well dimensions

cross section

We return to the wells. The cross section of reinforced concrete rings, from which in most cases they are constructed, depends on two factors:

1. Sections of the sewer pipe over which it is erected;
2. Depth.

For the first parameter:

If the depth of the well exceeds 3.0 m, then the smallest diameter of the rings must be at least 1.5 m.

The typical height of the well (its working part, measured from the tray to the cover) is 1.8 m. It is quite expected that this value is affected by the terrain - either upward or downward. For example, if the depth is >1.2 m, then the cross section should not be less than 1 m.

Depth

Regarding the depth of occurrence, it should only be said that this value depends not only on climatic conditions.

Soil loads should also be taken into account, for example, when a pipe is located under a roadway. The price of an error is very high - from the likelihood of freezing pipes in winter periods before damage or depressurization of the sewerage by vehicles passing over it.

In some cases, sewer pipes can be laid in a reinforced concrete tray, as well as additionally insulated.

Distances according to SNiP

Lookouts

Let's move on to the most interesting - knowing which type of wells we are talking about, we will find out the largest and smallest distance between sewer wells according to SNiP. Let's start with the manholes.

In practice, the distance is determined based on the cross section of the sewer pipe connecting two wells:

Diameter (Ø) of the pipe, m	Min. allowable distance, m
0,15	35
0,20 – 0,45	50
0,50 – 0,60	75
0,70 – 0,90	100
1,00 – 1,40	150
1,50 – 2,00	200
Over 2.00	250 — 300

Rotary and nodal

There are no specific values ​​regarding distances in the regulatory documentation for this type of wells. Why?

To answer the question, you should remember for what purposes they are built:

1. Nodal - in all places of connection sewer pipes;
2. Rotary - in all places where the pipe changes direction. Moreover, they must be taken into account by the project at each point of change in the slope of the landscape or the section of the pipe.

The pipe turning radius also plays a role:

1. If the pipe Ø exceeds 1.2 m, then the minimum turning radius is 5 Ø.
2. If the pipe is less than 1.2 m, then the turning radius is equal to its Ø.

Captain Evidence suggests: for pipes of large Ø at the beginning and at the end of the turn, manholes are built without fail.

Now you know that there are no specific figures indicating the distance between the nodal and rotary wells in SNiP - everything is determined individually when designing the sewer network of a particular object (house, quarter, district).

Variable

About drop wells should be told in more detail. Such structures are installed in places where there is a large difference in height between the incoming and outgoing pipes.

The very slope of the pipes of the external sewer network primarily depends on:

• landscape;
• Underground structures and structures encountered on the path of sewage flow;
• Depth of inlet pipe.

At the same time, the design of overflow wells will also be different. For example, to reduce the flow rate, the design of the well will be multi-stage. There are often designs where, instead of pipes, a simple channel is used, which has the required slope.

Pipes

Pipe Ø also affects the distance between wells. Let's find out this nuance.

When laying the sewer system, the following values ​​\u200b\u200bof the dimensions of the sewer pipes must be taken into account:

• 0.15 m for an intra-quarter network for domestic or industrial purposes;
• 0.20 m for the street sewer network;
• 0.25 m for street storm water.

If in a settlement the volume of wastewater is >300 m3 per day, then the smallest diameter for the intra-quarter and street network is 150 mm.

Sanitary protection zones

Another important aspect worth mentioning is the sanitary protection zones that affect the location of sewer wells. The parameters are determined by the performance and the type of structure used.

It is clear that such information does little for a simple developer in terms of practical application. Therefore, I will explain the parameters that must be adhered to when designing autonomous sewerage private household.

For example, let's take its productivity equal to 15 cubic meters per day:

• For the section of underground filtration of wastewater, the sanitary protection zone will be 15 m;
• For a trench filtering drains or a sand and gravel filter - 25 m;
• At least 5 m should be from the foundation to the septic tank and at least 8 m to the filter well.

The diagram indicates 3 meters - this is the minimum distance from the sewer to the foundation of the cottage. But we are talking about a nodal well!

Legal and legal liability

In legislation Russian Federation penalties are provided for violations of the requirements of SNiP for the design and installation of external sewerage, as well as a measure of responsibility.

The following persons are responsible for compliance with the rules and regulations:

1. design organizations - established responsibility for the correctness of plans, drawings and all preliminary calculations for the design of an external sewer network;
2. customers and developers - the responsibility for the preparation for operation of the installed sewer network has been established. This includes: personnel moments, the correct selection and operation of equipment, commissioning processes, etc.;
3. Research Institute - established responsibility for the issued data on climatic conditions in the region where the installation of the sewer network is carried out;
4. construction and installation organizations - full responsibility is established for compliance with all norms and rules during construction and installation works and testing of the completed structure.

When checking and identifying violations for these categories of persons, a decision is made to bring them to administrative, disciplinary and, in case of serious consequences, even criminal liability.

In the course of investigations of accidents related to the malfunctioning of the sewer network or its breakdown, specific perpetrators are identified and the degree of guilt of each of them is established.

Do not think that the responsibility lies only with those who design and build objects of state and municipal outdoor sewerage systems.
Any citizen who has independent design and installation of an autonomous sewer network is also responsible for violation of the requirements of SNiP and environmental laws.

The negligence or inaction of the responsible person, non-compliance with applicable rules and regulations, which led to an accident or breakdown or interfere with the normal operation of the sewer pipeline, is also classified as a violation with all of the above consequences for a particular culprit.

The purpose of writing this article is to put together the basic requirements for dimensions and distances that should be followed when laying a drainage system. We have to find out what the minimum distance between the sewer manholes can be, what is the size of the protection zone of the treatment plant and what the diameter of the sewer pipes can be. So, let's go.

Information sources

The main source of information for us will be SNiP 2.04.03-85 adopted in 1986 by the USSR State Committee for Construction. It regulates the laying of external sewer networks and the construction of related structures.

It is curious: almost simultaneously with it, SNiP 3.05.04-85 was adopted, which describes the requirements for laying external water supply and sewerage networks. If the first document is devoted mainly to the design of waste systems, then the second focuses on the materials used and the laying technology.

We have to gather a certain amount of information in another document - the set of rules of the joint venture 32.13330.2012. This is the updated version of SNiP 2.04.03-85 approved in 2013, which does not cancel its effect, but introduces some additions to the text.

Wells

Let's start with the requirements for the location of wells. To do this, we will have to start by studying their types.

Types and purpose

• Inspection wells serve to control the operation of sections of the sewage system and, most importantly, to clean it in case of inevitable blockages.
• Swivel - perform the same function at the points of change in the direction of movement of drains. Any bend in the pipe is always a high risk area; access to it completely solves this problem, allowing you to clear the blockage when it occurs.

In the photo - a rotary sewer well. At the turning point there is a revision for clearing blockages.

• Variables serve to compensate for too much slope. An excessive slope is no less harmful to the operation of the sewage system than its absence: an excessively rapid movement of effluents leads to the fact that solid fractions accumulate in the pipe, gradually reducing its clearance.
• Nodal are equipped at the junction of pipelines.

Location

The smallest distance between sewer wells according to SNiP for manholes is determined by the size of the pipe connecting them.

Diameter, mm	The smallest distance, m
150	35
200 — 450	50
500 — 600	75
700 — 900	100
1000 — 1400	150
1500 — 2000	200
Over 2000	250 — 300

Nodal wells, as you might guess, are equipped in all places where sewer branches are connected; rotary - where the pipe changes direction. In addition, they must be provided for by the project at the points of change in the slope or section.

Dimensions

cross section round well again determined by the cross section of the pipe:

• Up to 600 mm - 1 m;
• 700 mm - 1.25 m;
• 800 - 1000 mm - 1.5 m;
• 1200 mm - 2 m.

However: at a depth of more than 3 m, the smallest diameter is 1.5 m.

The height of the working part of the well (from the tray or shelf to the cover) is usually taken equal to 1800 mm. It is clear that the instruction is far from always applicable: the terrain may force you to increase or decrease the depth. If it is equal to 1.2 meters or less, the cross section increases by 300 mm relative to the above values; however, it should not be less than a meter.

The necks are made no narrower than 700 mm; when using large pipes, they should skip the cleaning tools.

Pipes

When laying the sewer system, you should rely on the following smallest pipe sizes:

In addition, SNiP regulates the slope of pipes.

It is relevant not only for external networks: the same values ​​\u200b\u200bshould be followed when laying internal sewerage with your own hands.

• For pipes with a size of 50 mm, the optimal slope is 0.035 (3.5 cm per linear meter).
• For 110 - 0.02.
• 150 — 0,01.
• 200 — 0,008.

Sanitary protection zones

Their size is determined both by the type of structure and its performance.

What should be the distance from the sewer to the foundation of the cottage?

Here are the parameters that should be followed with a private house (productivity - less than 15 cubic meters per day).

• The sanitary protection zone of the underground filtration field is 15 meters.
• For a filter trench or a sand and gravel filter, it is 25 m.
• A septic tank septic tank can be built 5 meters from the foundation, and a filter well - 8.

Turns, laying depth

What is the smallest turning radius of the collector pipe?

1. With its cross section up to 1200 mm, it is equal to the diameter of the pipe.
2. If the pipe is thicker than 1200 mm, the minimum turning radius is equal to five of its diameters.

Important: in the latter case, manholes must be built at the beginning and at the end of the turn curve.

What is the minimum depth to which sewers can be laid?

The value is determined, first of all, by the depth of soil freezing and the experience of operating sewer networks in the region.

If no operating data is available, the minimum is:

• With a cross section of up to 500 mm - 0.3 m above the depth of soil freezing;
• With a larger cross section - 0.5 m above the freezing level.

In both cases, the distance from the top of the pipe to the ground surface or the zero planning mark cannot be less than 0.7 m. The price of violating this rule is an increased likelihood of pipes freezing at the peak of frost and damage by passing vehicles. If for some reason the condition is not feasible, the pipes are laid in a reinforced concrete tray and additionally insulated.

Conclusion

We hope that the materials offered to the attention of the reader will help him in the design and independent construction. As usual, the video in this article contains additional thematic information. Good luck!

Wells play an important role in the operation of the sewer system. This is a necessary structure, without which the system will not function properly, or even completely clog. Sewer wells are not randomly located on the track, but have their own place. And each of them does their job. The number of installation of wells depends on the length of the route, turns, drops, as well as the diameter of the sewer pipes. The existing SNiP document clearly indicates the device, purpose, as well as the distance between the sewer wells. Let's take a closer look at all types of sewer wells, their purpose and their installation locations.

Inspection sewer wells

This type of wells serves to inspect and control the sewer system. They also clean the pipeline in case of blockage. Inspection wells are installed on a long straight pipeline, bends, at the points of connection of the side sleeves, as well as at the point of change in the diameter of the pipe or its slope. Distance between installed pipe wells different diameter calculated, guided by the SNiP document. On a straight line with a pipe diameter of 150 mm, the distance between the wells should be 35 m. For pipes from 200 mm to 450 mm, the distance will be 50 m. There is probably no point in listing larger pipe diameters. They are mainly used in central sewer systems, with a large volume Wastewater. As you understand, with an increase in the diameter of the pipe, the distance between the manholes increases. This is because a larger diameter pipe is less likely to clog. There are cases when the distance can be increased up to 50 meters on a flat track with the same pipe diameter and without side arms. In everyday life summer cottages and private yards for sewerage use PVC pipes with a diameter of 110 mm. On such networks, the distance between the wells can be reduced to 15 meters.

Rotary sewer wells

This type of well performs the same functions as a viewing well. Has the same device. And it got its name due to the fact that it is installed at the turn of the highway. Every turn or bend in a pipeline can become a blockage point. In order to have access to clean this section of the sewer, wells are installed at all turns and bends without exception. If the rectilinear distance between the rotary wells is large, then additional manholes are installed in this area.

Overflowing sewer wells

This type of well is installed in problem areas of the sewer, where it is impossible to maintain the correct slope of the pipeline. Take, for example, a large slope. In such a place, the correct slope of the pipeline cannot be maintained. And this entails a quick discharge of wastewater, which will not have time to take solid accumulations with them, and the pipe will clog over time. Therefore, in such places, overflow wells are installed according to a stepped system. The distance between such wells is determined individually and depends on the slope, but the difference should not be more than 3 m. If the sewer has a pipe diameter of up to 600 mm and the difference is less than 50 cm, it is possible to replace the overflow well with a viewing well equipped with a drain.

At the end of the sewer system, the so-called final well is necessarily installed. This is the place where all wastewater from the sewer is drained. It can be both filtering and accumulative. But the bottom line is that in front of this well or in front of a tie-in to the city highway, a control well is installed at a distance of 1.5 m.

Distance from the building

At the exit from the building of the sewer system, the first well is necessarily installed. According to the norms, it should be located at least 3 m from the wall of the building in the direction of the flow, but not more than 12 m. Basically, the length of the outlet of the manhole from the wall of the building should not be more than 8 m. If this distance cannot be maintained, then an additional well.

When building a sewer, keeping the distance between the wells, do not neglect sanitary standards. Remember that in addition to the correct distance between them, the distance of the well from the reservoir, drinking spring, garden plantings must be maintained. The distance to the water well depends on the material of the pipe from which the water supply is made. But in any case, at least 5 m. If it is a drain well, then it is located at least 10 m from the water supply.

As you understand, any sewer, built according to all the rules and regulations, eventually requires cleaning and maintenance. Therefore, so that you do not have to open the entire network when the pipes become clogged, install the wells correctly. Having withstood all distances in accordance with established standards, you can always get to the problematic section of the pipeline and carry out an audit.

Add site to bookmarks

Creating entry holes in reinforced concrete rings for pipes with a diameter of more than 250 mm, as a rule, leads to their damage. Therefore, for mines to which such pipes are planned to adjoin, the lower part of their main working chamber is constructed either from brick or from monolithic concrete.

One of the important characteristics of the working chamber of any well is tightness. Based on this, inner part finished hull sealed with bitumen. Sealing can also be done by lubricating the inside of the well cement mortar. For filtration shafts, tightness is not particularly important. In addition, a special hole is often built at the bottom of the working chamber for greater drainage.

Pipes that are adjacent to the well must be laid flush with its inner surface.

If, when laying a sewer, it is impossible to lay an integer number of products between two shafts, then its bell-shaped end must be cut off from the outermost pipe. The joining of the pipes to be mounted with the walls of the shaft is carefully sealed with cement mortar, both outside and inside.

The mouths of the wells must be arranged above the mouth of the largest supply pipeline. In pipeline shafts that have a rotation angle of less than 165°, the neck should be located above the outer flange of the tray (angle bisector).

The arrangement of water supply or sewerage in a private area requires a careful and measured approach. Especially the distance between the sewer wells and the installation of a drainage system from the house. If you do not follow the rules prescribed in SNIP 2.04.03-85, this threatens to pollute water supply sources through the ground, failure of the foundation of a house or any other structure, as well as disruption of the water supply and sewerage due to clogged pipes and the inability to provide proper repairs.

When installing water supply and sewerage pipes in a private house, it is necessary, firstly, to take into account all topographical factors that can affect the efficiency of communication. These are:

• All types of soils in the assigned area;
• The possibility and risk of stumbling upon a quicksand when installing a drainage well;
• The presence on the site or near it of a neighboring source of water supply (well, well, etc.);

Important: if you take into account the listed factors, the installation of sewer pipes near the house will be carried out in accordance with all the rules of SNIP.

Simple sewerage device

According to SNIP, the arrangement of the simplest straight collector near the house should take place provided that the receiving well is located at a minimum distance of 5 meters from the house and other buildings. Ideally, if the distance is increased to 12 meters.

In this case, the pipes must be located in a straight line without bends and turns at a slope towards the septic tank. The slope level must be an acceptable value and be at least 1 cm per 1 meter of pipe.

In such a well, settled water will drain into the ground through drainage, and the remaining particles of decomposed effluents must be pumped out using a sewer.

The device of the sewerage on a site with a problem relief

According to the rules of SNIP, the installation of a sewer collector with a complex configuration must be carried out according to the following rules:

• When using pipes of 100 mm diameter, the distance from the well to the well should be 15 meters.
• The maximum distance between sewer wells is regulated depending on the diameter of the pipes (assuming a straight collector). So, with pipes d = 150 mm, the distance between the wells can be 35 meters. This segment is considered optimal for effective work collector and its maintenance.
• If there is a place to be the arrangement of a complex collector for mass use, then according to the rules of SNIP, the distance between the manholes can be increased to 75 meters.

Important: the parameters described in SNIP apply only to collectors located in a straight line. Moreover, an increase in the diameter of pipes in a private area should be carried out only if absolutely all drains pass through the collector - storm, household, ground, etc.

Sewerage device with drops and turns

If the sewer collector has a complex configuration and many turns, then inspection rotary wells must be installed at the knees. Since it is these places that are the risk zone for the effective operation of the sewer, access to them must be year-round.

According to SNIP, the distances between rotary wells are not regulated. The number of rotary wells directly depends on the number of collector bends at right angles.

If we are talking about the complex terrain of the site, which goes down a large slope, then according to the SNIP, it is necessary to install differential wells, which must be mandatory. Thanks to such tanks, the speed of wastewater will be reduced, which means that the entire sewerage system will be protected from sedimentation of sewage sludge, which can move at high speed under a large slope. This is absolutely impossible to avoid in order to avoid blockages in the collector.

According to SNIP, when installing drop wells, the following requirements must be met:

• The total height in the case of one drop should not be more than three meters;
• If the drop is minimal and its height does not exceed 0.5 meters, and subject to the use of pipes, d of which is 600 mm, the drop-type tanks can be replaced with viewing tanks, but subject to the presence of a drain. But it is known that when arranging sewerage in a private area, pipes of 100 mm diameter are mainly used, so the installation of an overflow tank cannot be avoided.

Important: if you find it difficult to independently develop a plan for the location of the sewer collector, taking into account all the rules, then it may be better to invite specialists who will draw up correct scheme pipeline installation.