How a Septic System Works
If properly designed, constructed and maintained, your septic system can provide long-term, effective treatment of household wastewater.
Septic tanks provide treatment of water coming from your home or business, and work in the same way as a large, private sewage treatment plant. They are composed of pipes leading into and out of the tank, the septic tank itself, and a drain field. With careful maintenance including regular pumping, septic tanks are an economical sewage solution that also help protect the environment by requiring less pipe installation.
Waste water flows from your home or business into the tank, where the wastewaer is allowed to decompose using naturally occurring bacteria and then released into the drainfield. To further explain the decomposition process of the wastewater, let’s imagine we are looking at a cross section of a septic tank.
The water has just made its way into the septic tank through a sewer pipe, and will settle in the tank until the waste and water separate with time. Waste such as oil and grease will float to the surface of the septic tank, creating scum, while solid waste heavier than water will fall to the bottom, creating sludge.
While bacteria naturally found in the waste are working to break the waste down, the partially clarified waste water that remains in the center of the tank is then filtered through a pipe into the drainfield area, also called a leachfield or disposal field. Oftentimes screens are used to ensure that no solid waste enters the drainfield area, and this solid waste is cleared out each time the septic tank system is pumped.
As the wastewater enters the drainfield, it is carefully filtered and distributed through a series of trenches, gravel and perforated pipes that allow the water to release slowly, with the gravel acting as filters.