Private Sewage Disposal Systems
In order to clearly understand what a Private Sewage Disposal System (PSDS) is and does, it is important to define the terms for the major parts of a traditional system.
Septic Tank: The rectangular concrete box like structure or a fiberglass submarine shaped structure. The main purpose of a septic tank is to separate the solid waste from liquid waste and to allow for bacterial digestion of solid waste. This is usually the closest unit to the house and the waste lines from the house flow into it. Some locations require that an advanced high technology septic tank be installed. AdvanTex is the advanced technology septic tank we like to install.
Cesspool: The structure of a cesspool is the same as the structure of a seepage pit. The difference between a cesspool and a seepage pit is that the cesspool is connected directly to house waste lines and receives solid waste and water like a septic tank. Cesspools are also able to percolate water into the soil like a seepage pit. Around 1952 the building code changed and cesspools are no longer allowed according to the Uniform Plumbing Code for permanent installations. Septic tanks are now required on all new private sewage disposal systems. Most cesspools that still exist by now are completely worn out, percolate very little or no water into the soil and function more like a septic tank.
Seepage Pit: A cylindrical or well like deep hole in the ground anywhere from 12' to 60' in depth. The seepage pit is lined with bricks, special concrete blocks or pre-cast concrete seepage pit liners, which allow the water (effluent) flowing from the septic tank or primary cesspool to percolate or be absorbed into the soil. When the seepage pit stops percolating water into the soil you need to install another seepage pit or a Pirana. A Pirana is the newest concept in waste treatment that is the least expensive way to help improve the percolation of your seepage pit.
Leach Line: This is a trench 1 to 3-feet wide, 50-100-feet long, 4-6-feet deep, filled with 1 to 3-feet of -inch gravel, with a perforated pipe laid on top of the gravel. The water from the septic tank then flows through the perforations in the pipe into and then through the gravel and is absorbed or percolated into the surrounding soil.
How do these systems work?
All the water and solid waste generated form the house flows directly into the septic tank or primary cesspool. As the water slowly passes through the septic tank whatever floats, floats and whatever sinks, settles to the bottom and reasonably clear effluent than flows out through the "outlet septic tee" or an "effluent filter" into either a seepage pit or a leach line and then soaks into the surrounding soil.
If you have a pre-1952 system, it most likely will consist of a primary cesspool with either an additional seepage pit(s) and/or leach lines. What this means is that your primary cesspool will be functioning as a septic tank, even though it is not a septic tank, which separates the solid waste and allows the effluent to flow to the seepage pit(s) and/or leach lines.
