How Do Septic Tanks Work

A septic tank is one of the key components of a septic system, others being sewer line and leaching system. It is a large tank made up of either concrete or steel, with a capacity to hold up to 1,000 gallons of water at a time. It is a small-scale sewage treatment plant, mostly found in places that are not connected to the main sewage pipes, as provided by local governments or private corporations. Septic tanks are joined to other waste treatment components, such as bio-filters or aerobic systems, involving artificial forced aeration. It consists of a large tank, which is connected to an inlet wastewater pipe at one end and to a septic drain field at the other. The tank requires regular maintenance to keep up with its proper functioning. If properly maintained, a septic system can last for decades or even your whole lifetime. Read on to know how do septic tanks work.

Functioning Of A Septic Tank

The septic tanks used these days contain two chambers that are separated by means of a dividing wall.
The wall has an opening that is located in the center, between the floor and roof of the tank.
The wastewater flushed from the toilets enters the first chamber of the septic tank.
Here, the solids settle on the floor, while the scum floats.
As the settled solids are anaerobically digested, the volume of the solids reduces subsequently.
The liquid component passes into the second chamber, through the dividing wall, where further settlement of waste takes place.
The excess liquid, which is in a relatively clear condition, is drained into the leach field, drained field or seepage field, depending on where the outlet is located.
The remaining impurities are trapped and eliminated into the soil of the leach field.
The wastewater is then distributed throughout the leach field, through multiple drainage holes, to aid dispersion.
The water is then absorbed into the ground, providing nutrients to fertilize the soil.

Tips

A septic system should be sized correctly to avoid clogging and ensure even and timely movement of the wastewater.
Apart from proper functioning, a septic tank also requires periodic maintenance. The irreducible solids that settle down and fill the tank gradually should be removed; else, the efficiency of the tank will go down.

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