The question of how often it is necessary to pump out a septic tank occupies many owners of summer cottages and private houses. Calling the cesspool machine involves time and money, and a delay in pumping can lead to clogging of the storage, unpleasant odors and environmental pollution. Specialists recommend pumping out at least 1-2 times a year. We will understand what this period is due to, what factors affect the frequency and quality of cleaning.
How does a septic tank work?
If it is not possible to connect the sewerage of the house to the main pipe leading to the municipal sewage treatment plant, the problem of storage and disposal of domestic wastes arises. This is dirty water from the bathroom, kitchen and toilet.
The wastewater contains liquid and solid fractions. At the same time, at least 70% of the volume is water. Many components of sewage are food for microorganisms. Vital activity of bacteria leads to partial or complete biological decomposition of organics. This process is accompanied by unpleasant odors, and many bacteria and their metabolic products are dangerous to humans.
There are two ways to solve the drain problem:
- Cesspool. This is a reservoir in the earth whose walls are capable of passing water. Solid components remain in the pit, forming silty deposits. They need to be pumped out every 6-12 months, otherwise the pit will overflow. A cesspool is the simplest but not the cleanest solution to the sewage problem. It spreads an unpleasant odor, and the sludge contained in the pit pollutes the soil.
- Septic tank. This is a complex structure of several concrete chambers in which sewage water is sedimented and the sludge is gradually decomposed by bacteria. The water purified as a result of biological destruction enters the last chamber - the filtering well. This chamber has a permeable bottom, and the water leaves the soil without polluting it. The septic tank must be cleaned of sludge every 2–4 years.
A septic tank is a much more advanced device than a cesspool. It does not take up space on the site (tanks are located underground), does not smell due to the hermetic design, does not infect the soil with extraneous microflora. However, it should be monitored and cleaned as necessary.
There are more complex designs of septic tanks, which are stations of complete water purification. In them, the liquid is purified so that it can be used for technical needs. For example, the TOPAS autonomous sewage system provides 98% wastewater treatment.
What determines the frequency of cleaning?
It is impossible to unequivocally answer the question about the timing of cleaning the septic tank. The fact is that for different models this period can differ quite significantly (from 1 year to 5 years). The mode of operation and the amount of wastewater received for processing per day is also different in different families. For example, a family of 5 people permanently living in the house will produce much more effluents than a couple of pensioners who visit the country only on weekends.
Here are the main factors affecting the frequency of pumping the septic tank:
- The septic tank capacity. The larger the tank, the less often it is necessary to clean it.
- The average volume of daily wastewater. This indicator depends on the number of people constantly using sewers and the frequency of its use.
- Designs of a drainage well. Different materials conduct water at different speeds, so the rate of removal of purified water differs for different models of treatment plants.
- The type of microorganism used for biological destruction. A number of septic tanks are designed for the use of only anaerobic bacteria, in others, anaerobic and aerobic cultures are successively decomposed. The first variety is cheaper, but it conducts cleaning more slowly and, therefore, often needs pumping.
When calculating the necessary capacity of a septic tank, it is worth taking into account not only the needs of people living in the house, but also the needs of potential guests. Otherwise, the treatment system may not cope with the peak load.
The cleaning time for a specific model is specified in the accompanying documentation. It is rather advisory in nature, but neglected is not recommended. Otherwise, silty sediments at the bottom can cake together in a dense crust, which will significantly complicate the cleaning and resumption of the system.
To pay to cesspool workers or to pump out silt by itself?
Even the most advanced septic tank requires cleaning over time. With proper settings, the liquid level in the tank practically does not increase, but its composition will gradually change due to the accumulation of sludge. To ensure that the sludge does not cake over time into a dense crust, it is necessary to periodically pump out.
There are two ways to clean the septic tank from excess sludge:
- Call the cesspool machine and entrust the matter to professionals.
- Armed with a fecal pump, a tank for transportation and solve the problem on your own.
Each option has its own advantages and disadvantages. We will analyze them in more detail to choose the optimal solution.
Invitation of scavengers - simple but expensive
Today, in most settlements there are several organizations involved in the pumping and removal of sewage. Having made the call of the cesspool machine in such an organization, it remains to wait for the arrival of specialists on the appointed day and to monitor their work.
This option has a whole set of advantages:
- No need to buy complex and expensive equipment. The savings are especially noticeable, since the transport tank and the fecal pump will be needed only 1 day a year, or even less.
- No need to look for a place to dispose of wastewater.
- You can not do dirty work.
It's comfortable!
Most organizations offer not only a one-time cleaning service for an autonomous sewer system, but also contracts for ongoing maintenance. After the conclusion of such an agreement, the employees of the sewage service will themselves go to service your septic tank according to the established schedule.
The main drawback of contacting professional scavengers is the need to pay for their services. The cost of maintenance depends on the distance to the company’s office and the volume of drained effluents. Such costs can be a significant expense item.
We clean the septic tank ourselves: save money, spend time and energy
The procedure for pumping a septic tank is not too complicated, but it requires the possession of some specific skills and the availability of special equipment:
- Fecal pump. Do not use the water pump, as it will quickly clog up with the solid components of the effluent and fail.
- Barrels for transporting sewage. They are available in the form of car trailers or bodies. The tank must be resistant to corrosion processes, have a sealed lid. It is better if the barrel corresponds to the volume of the tank of the sewer system - this will allow to pump out all the drains at a time.
There is no oxygen in the anaerobic digestion tank. In the process of biological destruction, toxic gases accumulate, so if you take careless actions you can seriously poison yourself.
Before cleaning, you must contact a nearby waste disposal site and agree on the collection of wastewater. On the day appointed for the work, sludge is pumped out of the tanks along with water. In this case, it is necessary to leave about a fifth of the sludge as a starter culture - it contains a colony of bacteria that conduct biological destruction.
After pumping out, large solid waste (tangles of hair, fragments of bones, rags, etc.) is removed from the tank. Then you need to clean the filters, and then fill the tanks again with clean water. The process is quite time-consuming and dirty, so it’s worth taking on it only when it is impossible to call the scavengers.
Timely pumping of a septic tank is a necessary condition for the uninterrupted operation of the sewage system in the house. Do not forget to hold this event according to the established schedule!