How Septic Works

septic tank inspections: ajax pumping


What is a Septic System & How do They Work?

Septic Tank: Waste water flows from the house to the septic tank. The tank is designed to retain waste water and allow heavy solids to settle to the bottom. These solids are partially decomposed by bacteria to form sludge. Grease and light particles float, forming a layer of scum on top of the waste water. Baffles installed at the inlet and outlet of the tank help prevent scum and solids from escaping. Newer septic tanks have a concrete dividing wall, thus making two compartments. This helps ensure the sludge does not get forced out of the tank and into the drainfield. Newer tanks also have two manhole covers. Both of these manhole covers need to be exposed for proper cleaning. In addition most homes built after 2001 have an effluent filter in the rear compartment that also needs to be serviced regularly.

Septic System: Care and Maintenance

Conventional septic systems are not entirely care free. The undigested solids (sludge) in the bottom of the septic tank should be pumped out every three to five years, depending on usage and tank size. If the sludge is not removed periodically, it will eventually carry over into the leach field and cause the field to fail.

A well designed system can handle a reasonable amount of normal household chemicals such as drain cleaners, laundry detergent and bleach; excessive usage can be detrimental. You should avoid putting in chemicals that are toxic to the bacteria, such as paint thinner, solvents, insecticides, etc. Cooking fats and grease should also be avoided. If a garbage disposal is used, more frequent tank pumping may be needed.


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