How it works

What is a Septic Tank and How a Septic Tank Works

All plumbing fixtures in a home are connected to a septic tank. A septic tank system is based on a watertight container made of fiberglass or concrete. The solids reaching the tank (including paper, oils, grease, and waste) form a layer on the surface, which is usually referred to as “scum”. With time, the scum is broken down and eventually drops to the bottom of the septic tank, resulting in a layer known as “sludge”. Between the layers of scum and sludge there is only clear water, which should be drained from the septic tank onto the drain field.

There are a number of different kinds of drain fields with the two most frequently used ones being the chambers and mineral aggregate. In case of the aggregate drain field there is a ½” layer of rock, sandy soil covered by rocks, housing a perforated pipe with a diameter of 4”. On the other hand, the chambered system comes in a dome shape with openings along the sides and an open bottom that would fit the trench of the drain field. When the water drains from the tank, it is evenly distributed along the circuit of pipes on the drain field. The water runs through the perforated pipe onto the rock bed, where it sits until it is absorbed by the sand.

After a while the solids will build up in the tank and it will require to be cleaned. This process is known as septic pumping or septic tank cleaning. Regardless of what you call it, it’s still an important step of septic tank maintenance. If the septic tank isn’t regularly cleaned, the solids will build up and they will flow out onto the drain field. The organic matter will clog the gaps between the rocks, forming a thick layer in the drain trench. As a result, the water won’t drain from the septic tank, resulting unsafe and unsanitary conditions. Water will flow in any direction it can; if it can’t flow out onto the drain field, the water will come out on the top of the tank, flooding the backyard or it will return to your home again.

When the septic contractor comes to clean the tank, they should clean it through the manhole of the septic system instead of the inspection ports. This is something you should insist on, since it ensures that all the solid matter will be cleaned out. Also make sure that all the solids are removed and there is nothing left in the septic tank. If here is any solid matter left behind, it could clog the drainpipes, which might result in expensive septic repairs sometime soon.