Learn about what really goes into a septic system and how they work.
Septic systems are another great option for waste water treatment. Unlike sewage systems they run solely on gravity for the most part and require no outside power to run effectively. The design is simple and relatively inexpensive to build. The septic tank itself is a large rectangular or cylindrical tank made out of either concrete, fiberglass, or polyethylene. The tank is buried under the ground in the owners yard, and has an access point on top for pumping out solid waste. The average sized septic tank for a normal household is about 750 to 1250 gallons. PVC pipes run from the house into the septic tank at the inlet baffle. From there the waste water is contained in the tank, then released out the outlet baffle where it runs through a sequence of perforate pipelines under the ground called a "leach field" which then release the waste water into the ground soil. While inside the septic tank the solid waste sinks to the bottom making a "sludge layer". The grease and oils float to the top creating the "scum" layer. Finally, directly in the middle the waste water is the only matter allowed to escape through the outlet. A common misconception about septic tanks is that the waste water goes untreated however the water is treated through a natural process called effluent absorption and purification. This process is where the waste water floats through the pores in the soil and the small grains and natural bacteria capture and treat the harmful organisms that may still be in the water. Next, the water reenters the ground water and can be consumed. Generally households acquire their water from wells which are natural springs that are connected to the ground water. This is not a problem however because it is found that upwards of 90% of disease causing bacteria are filtered out during this process, and the rest are diluted in the ground water so they will not be consumed in high quantities which can be harmful. This process is just as effective as the large scale waste water treatment plants however, it is all natural and requires no additional chemicals. The sludge and scum that remains in the tank is pumped out by professionals when the septic tank becomes too full, and is disposed of in an environmentally friendly manner. An important part of having a septic tank is properly maintaining it. Because it is not regulated by the town or city, it is up to the homeowner to pay for damages, therefore proper treatment of the system is crucial. Important precautions to take as an owner is to make sure you pump out the tank as much as necessary, if the sludge layer becomes too thick the tank will fail, and release harmful bacteria into the ground at too high of a rate. Secondly it is important that no slowly decomposing materials are flushed into the system such as diapers, rags, cigaret butts, etc. This can clog the system up and cause it to fail. As long as these precautions are followed properly the system can last upwards of 30-50 years.
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