6 tips for placing a septic tank on the site

9 min

Many of us remember the times when an outdoor toilet and outdoor shower were the pinnacle of landscaping a suburban area. Today, similar elements are still found in dachas, but the requirements for the level of comfort have long grown, and even in nature, modern man does not want to deprive himself of the benefits of civilization. So humanity came up with the idea of ​​installing septic tanks, which made it possible to equip the house with the usual shower and toilet. Septic tanks are certainly convenient and practical, but there are certain risks associated with them. To reduce them to a minimum, you need to know all the nuances of the correct location of the septic tank on the site. We study the regulatory framework and expert advice.

Design features of septic tanks

An ordinary cesspool is not a completely safe solution. The effluents that enter it are absorbed into the soil and can penetrate into the groundwater, and they feed the wells that are used to obtain drinking water. It turns out that drinking water can become toxic. Of course, with the correct location of the cesspool, it is possible to reduce the likelihood of such a development of events, but nevertheless, this solution is no longer modern. And why use the old-fashioned way, when a modern septic tank is not so expensive, but many times more reliable.

According to the principle of operation, septic tanks can be divided into the following types:

  • storage tanks are an improved sump. A septic tank of this type is a sealed tank in which drains simply accumulate, from time to time such a septic tank must be cleaned. The main plus in comparison with a cesspool is that there is no contact of drains with the soil, and therefore the risk of its contamination is minimized. Storage tanks are suitable for summer cottages where there is little wastewater;

  • sedimentation tanks allow not only to accumulate, but also to purify waste water, which greatly simplifies the operation process. The septic tank consists of two or three chambers, in each of which a certain stage of cleaning is carried out. The first section is usually the most voluminous. It is intended for the accumulation of effluents and their primary sedimentation, sediment settles at the bottom, and more or less purified water flows into the second reservoir, where smaller particles leave in the sediment. The third reservoir is a compartment with a biofilter, where water is further purified, but it may be absent. Then comes the stage of soil filtration. The solid sediment gradually thickens, and the bacteria contained in the effluents partially process it, therefore, the septic tank has to be pumped out infrequently – about once a year. Sediments are relatively inexpensive, but for high-quality cleaning it is necessary to choose containers of sufficient volume, plus take care of the arrangement of soil filtration;

  • a septic tank with deep biological treatment is already more sophisticated equipment. At the first stage, the drains settle and then enter the section with the aerator. In the presence of air, aerobic bacteria process most of the sediment, then sedimentation occurs again, and the purified water can be removed from the septic tank, however, first it passes the crushed stone filter. Septic tanks of this type are compact, have a minimal presence of odor, do not require pumping, but are expensive. In addition, an electricity connection will be required, which is also a cost.

To ensure maximum tightness, it is better to take septic tanks of industrial production, but some craftsmen undertake to make such equipment with their own hands. So, depending on the material of manufacture, septic tanks are:

  • plastic – the best option in terms of tightness, price, corrosion resistance and weight. Ready-made septic tanks are sold in different sizes, they are designed to process different amounts of sewage.

    Eco-Septic – online store

    A wide selection of plastic septic tanks is offered by the Eco-Septic company, the assortment can be found on the website https://septik-moscow.ru… The company’s specialists will be able to advise the best model for your particular house, given the volume of drains. If necessary, the company’s employees will come and analyze the features of the site, the level of groundwater occurrence and determine the optimal place for a septic tank, taking into account all regulatory requirements. The list of possible services includes delivery, installation and maintenance of equipment, all work is guaranteed.

  • reinforced concrete septic tanks can be monolithic or prefabricated. The latter are mounted from concrete rings, but the tightness of such a structure becomes worse over time. Monolithic structures are more reliable, but they are more difficult to mount. The main disadvantage of concrete septic tanks is a large weight;

  • a brick septic tank can be laid out even with your own hands, and you can make tanks of any shape and size. Minus – insufficient tightness, even if the waterproofing work is carried out correctly;

  • metal septic tanks are rarely used. Although they are durable, lightweight and easy to install, they quickly rust and lose integrity under constant exposure to sewage.

Homemade septic tanks, which are made of bricks, concrete rings, tires and plastic containers, are able to purify wastewater by 60% and no more, while industrial septic tanks can cope with this task much more efficiently, cleaning sewage by 99%. But even the most expensive industrial septic tank is not a guarantee of complete comfort and safety. You need to know where to place the septic tank so that an unpleasant odor does not penetrate into the house, and toxins from drains do not enter the drinking water.

What is the danger of a septic tank?

A septic tank is associated with the following risks to humans and the site:

  • flooding of buildings;
  • pollution of the site with sewage during overflow and untimely cleaning of the septic tank, or during floods;
  • the most important danger is the ingress of waste into the ground and aquifers, i.e. literally into your glass. How can this happen if the plastic tank is strong and sealed? There are several reasons for this. These are errors during installation, errors in choosing a place for a septic tank on the site, as well as rupture of pipes and depressurization of the joints. Alas, no one is immune from emergencies – we can only reduce the severity of the possible consequences, and this is possible if we find the most suitable place for a septic tank, away from wells, wells, reservoirs.

Of course, ideally, it is better to choose a place for a septic tank at the planning stage of the entire site. Then it will turn out to arrange all the buildings and communications in an ideal way. But more often you have to look for a suitable place when the house with the barn has been built and the site has been ennobled. In this case, it is better to draw a plan of the site on a scale, designate the house, all outbuildings, a fence, neighboring houses, trees, wells and wells. Then you need to arm yourself with a ruler and look for the optimal place so as not to violate any of the following rules. If independent research has not yielded results, it is better to call for help from specialists who will additionally analyze the type of soil, the depth of the groundwater and indicate the best place and depth for installing the septic tank.

Legal and regulatory framework

Several documents concern the location of the septic tank on the site, therefore you will have to deal with each of them:

  • SanPiN 2.2.1 / regulates the requirements for sanitary zones around objects potentially hazardous to the environment;
  • SNiP 2.04.03-85 – rules for organizing external sewer networks;
  • SNiP 3.05.04-85 and SNiP 2.04.01-85 – requirements for external and internal water supply and sewerage systems, if a well or a well is used as a water source;
  • SanPiN – requirements for measures aimed at ensuring the purity of surface waters.

All the numbers, details and requirements in these documents are set out in great detail, but we will give all the most basic data below so that you have an idea of ​​the process of selecting a place for a septic tank. But just take and start digging a pit to install a container in a certain place will not work. First, you need to draw up a construction project, which will be approved by the SES, and if everything goes well, you will be given a building permit. The project, if desired and with the proper skills, can be prepared independently, but many still prefer to contact specialists.

Next, we will study the basic requirements for the location of the septic tank on the site, the specific norms of the distance from it to other objects.

Septic tank, buildings and communications

Most often, the owners of suburban real estate are interested in how far from the house it is better to place a septic tank. It seems that the cheapest way to put it right next to the walls, but at the same time, it is scary to do so, since there is a risk of unpleasant odors entering the house. The standards advise you to adhere to the following:

  • from the foundation of the building to the septic tank must be at least 5 m;
  • if the distance is less, then this promises not only aromas, but also the possibility of flooding the house during an accident or, for example, in spring with a sharp melting of snow;
  • You should also not be too careful, because a long pipe system is more expensive, more complicated, and the risk of blockages is higher. If there is no other option, then for every 10-15 m of the sewage system, an inspection well is provided;
  • the distance between the septic tank and outbuildings must be at least 1 m;
  • the distance between the septic tank and the water supply pipes is at least 10 m;
  • if there is an underground gas pipe, it is necessary to maintain a distance to it of at least 5 m;
  • the distance between the septic tank and fruit trees is 3-4 m. If you do less, then the roots run the risk of rotting, and the plants themselves are saturated with harmful substances.

Septic tank, fence and neighborhood plot

When planning the location of the septic tank, neighboring areas have to be taken into account:

  • first of all, you must take into account all the same requirements that apply to your own site. So your septic tank should be located at least 5 m from the neighbor’s house and 4 m from the trees, also do not forget about the optimal distance between the septic tank and communications;
  • the distance between the septic tank and the fence with a neighboring site is at least 2 m;
  • the distance between the septic tank and the road is at least 5 m. Do not forget that septic tanks periodically need maintenance, so it is necessary to provide for the possibility of access for special vehicles.

Septic tank and wells

The most important thing when thinking over a place for placing a septic tank is to ensure its sufficient distance from a well, a well and natural water bodies. The goal is to find such a place on the site so that even in the event of an emergency, sewage would not mix with clean water. The permissible distance is calculated taking into account the type of soil, taking into account the relationship between the filter and aquifer:

  • the minimum distance from the septic tank to the water intake point is 25 m (if clays lie between the septic tank and the water intake), the maximum is 50 m (with the predominance of sand and loam). Hydrogeological studies will help to determine the type of soil;

  • there must be at least 50 m between the well and the septic tank;
  • between a septic tank and a pond, lake, other objects with stagnant water, there must be at least 30 m;
  • between the septic tank and the river, stream, other body of water with running water should be at least 10 m.

It is optimal to place the septic tank lower than the water intake facilities, but this is not possible for all areas. However, it is impossible to hide a septic tank in the lowland, otherwise during floods and heavy rain the container may overflow.

It is also necessary to take into account the depth of the groundwater. Arrangement of an underground septic tank is possible at a depth of at least 1.5 m. If the groundwater is located higher, then an above-ground treatment system will have to be installed.

It is also important to take into account the depth of soil freezing. Ideally, a septic tank should be placed below this level, so that in winter there are no problems with frozen sewers and with all the ensuing consequences. If this recommendation is unrealistic, then it is necessary to insulate the pipes with high quality, or, as an option, install a heating cable.

If, after independent attempts to find the optimal place for the septic tank, you have a feeling that the calculation is not entirely correct, it is better, of course, to seek help from specialists.

[Total: 0   Average: 0/5]


Passionate about DIY for over 10 years and all the new tools, I give you through this blog all my advice, tips, tests in all areas: carpentry, electricity, masonry, gardening, home automation ...


Your email address will not be published. Required fields are marked *