For a private house, it is important to have autonomous communications. Sewerage is in the first place here. Considering that sanitary standards prohibit the discharge of effluents into the ground, a sealed cesspool should be made without pumping out with your own hands - a full-fledged septic tank. The percentage of dirty water clarification in it is up to 85%. This means that the environment will not be harmed.
Types of cesspools and device
For the final discharge of fecal masses and domestic wastewater, craftsmen often mount the following cesspools:
- Leaky, with an earthen or drainage bottom. The principle of operation of such a receiver is that all the drains through the sewer pipe from the house fall into the pit. Here there is a partial removal of water into the ground. Thick impurities remain in the receiver in the form of sludge. Later, the reservoir is densely overgrown with such a fecal-fatty crust and requires careful cleaning. Water leaking into the ground from such a reservoir seriously poisons the soil and groundwater. Leaky receivers are often made from improvised means - car tires, tires. This solution does not save the environment in any way.
- Sealed pit. The well is dug into the ground and completely laid out with bricks, reinforced concrete rings or poured with mortar. The tank has concrete walls and a bottom. The effluent enters here and is then removed using a sewer truck. Often, owners use special bacteria to somewhat reduce the amount of dirty water and the number of pumpings required per year.
- A septic tank is a full-fledged local sewage treatment plant, made by hand. For such a cesspool made of concrete or plastic, the presence of 2-3 chambers is characteristic. Each of them has a separate function. In the first receiver, the drains settle and the large debris is separated from the water. Fractions either rise up or sink to the bottom. The primary clarified liquid is poured into a second reservoir. The same principle occurs here, only the wastewaters are already freed from smaller impurities. Clarified water goes into the third chamber with a drainage bottom. From here, 85% purified liquid seeps into the ground.
There are aeration tanks on sale that run on electricity and purify wastewater by 98%. This water can later be used for domestic purposes (watering, car washing, etc.).
Choosing a place for a cesspool
According to SNiP, a pit with a sealed or leaky bottom should be located in a certain place on the site. The requirements are as follows:
- To locate the receiver, select the lowest point of the allotment. This will allow the collector pipes to be arranged with the desired slope so that the wastewater can be sent by gravity into the tank.
- The distance of the pit from residential buildings is made at a distance of at least 5 m.
- The source (well, well) should be adjacent to a reservoir for fecal waste at a distance of 20 meters or more.
- You need to remove the camera at least 3 meters from the neighbor's fence.
It is necessary to position the pit in such a way that, if necessary, a sewer truck can drive up to it. Sooner or later, the accumulated sludge will have to be removed from the receiver.
Carrying out the necessary calculations
The depth of the tank directly depends on the level of groundwater at the site. The higher it is, the shallower and wider the pit will be. Do not forget about 30 cm deep on the sand bed under the concrete bottom of the receiver.
If a decision is made to lay out the walls of the tank with bricks, it is also necessary to calculate the number of blocks. To do this, divide the height of the receiver by the height of one brick and get the number of rows that will be laid out on one side of the tank. The value is multiplied by 4 (four walls). We do the same operation with the width of the sides of the pit. We divide each of them by the block width. Thus, we get the number of bricks in one row. It remains to multiply the resulting value for each side of the pit by the number of its supposed rows from the floor to the top.
Choice of materials
An insulated cesspool can be made from concrete mortar, pouring it into the formwork, or from brick blocks. Sometimes the receiver is mounted on polymer barrels, but this option is more suitable for summer cottages. Each master chooses a method that is more beneficial and convenient for him.
A pit made of blocks is no less airtight than a monolithic tank. However, over time, brickwork can burst under the pressure of heaving soil. Therefore, if such soils are on the site, it is better to fill in a reinforced concrete structure.
When installing a pit from reinforced concrete rings, you will have to hire special equipment. The depth of such a receiver must be fair to support the required volume.
Installation steps
To arrange a sealed receiver with your own hands without pumping out, you need to prepare a foundation pit for it. Earthworks are best done in late summer or early autumn, when the land is as dry as possible. According to the established markings (in accordance with the diagram), the top layer of fertile soil is removed and removed to the side. In the future, the soil can be used in the garden. If you don't have the strength or time to work with your hands, you can hire a bucket excavator. Agile models quickly cope with the task.
If the construction of a septic tank is envisaged, a pit is being dug next to the second and third chambers. The total output volume of receivers is divided in the following proportions 50: 35: 15% (1: 2: 3 pits).
- To properly fill the sewer pit with your own hands, you should carefully tamp the bottom of the pit, pour a layer of wet sand. It also compresses well. A layer of roofing material is laid on top for waterproofing and then a reinforced mesh.
- A concrete mixture is prepared in the following ratios 1: 3: 5 (cement: sand: crushed stone). All are diluted with water to medium density.
- Formwork boards are mounted along the bottom perimeter. It is poured with a cement mixture to a height of 15-20 cm. The bottom is allowed to dry completely.
- As soon as the lower part of the pit is ready, formwork boards are installed around the perimeter. The walls are reinforced with metal rods and concrete is poured. At the same time, it is important to work it out well with a metal rod in order to expel air, otherwise the walls may turn out to be porous.
- The finished pit is well dried, but not in the open sun. It is advisable to shade this area and periodically moisten the solution so that it does not crack.
- As soon as the walls are ready, they can be coated on the outside with bitumen mastic and only then backfill the chamber.
The brick pit also has a concrete bottom. The finished masonry can be plastered from the inside with cement mortar.
Common mistakes
Often, when arranging a sealed chamber for drains, masters make the following mistakes:
- Incorrectly selected location for the tank. If it is located at a high point of the site, you will have to make a pressure sewer.
- Incorrect pit volumes. Too little can lead to accidents. A large chamber leads to stagnation of drains (when it comes to a septic tank).
- Improperly traced reservoir path. It is forbidden to make 90 degree turns of the pipes.If you cannot do without this, it is better to use special adapters of 35-45% or drop wells.
- Errors in the installation of overflow pipes (for a septic tank). Each introductory tube should be located above the outlet. Otherwise, the backflow of wastewater will occur. The overflow pipe should always be slightly inclined towards the receiving chamber. The first input waste tube is always mounted in the upper quarter of the pit.
Taking into account possible errors, the master can independently build a full-fledged sealed sewer pit or septic tank.
