How Septic Systems Work
How Septic Systems Work
Septic tank and drain field were developed in the late 1800’s.Today over 50 million people in the United States use septic systems to manage gray water and black water for their homes and businesses. As more people who are unfamiliar with septic systems move out to unsewered rural communities, the potential for septic system failures increases.
See below for a basic understanding of how septic systems work and what it takes for successful septic system installation and use.
How Septic Tanks Work
Septic tanks today are typically constructed of concrete or fiberglass. They are designed to have solids settle in the tank and are digested by anaerobic bacteria. The gases produced in this process are vented from the septic tank through the household plumbing vents. Non-biodegradable materials that aren’t digested by the microorganisms, and accumulate as sludge or scum layers. These sludge and scum layers must be removed periodically as part of a regular maintenance regimen. Appliances like washing machines, dishwashers, and garbage disposals increase the amount of sludge, and require more frequent servicing
Wastewater and Soil Absorption
Wastewater consist of graywater from washing machines, showers, and sinks that go into your tank and distribute out to the drain field. It is absorbed by soil particles and the dissolved organic material is removed by bacteria which lives on the top ten feet of the soil. As it drains through the soil, the temperature and chemical makeup of the wastewater create a hostile environment for bacteria and viruses. So as the wastewater percolates downward through the soil, organic material and microorganisms are naturally removed and the water eventually enters the groundwater aquifer.
Leach Fields
Consist of a series of perforated pipes placed in trenches and pipe is placed on top of gravel. The gravel assists with drainage and discourages root growth in the leach field. Paper or straw is placed over the gravel and to keep soil from entering the gravel bed (These materials are porous enough for to allow for natural evaporation). A layer of soil is added to cover the gravel, protect the leach field, and prevent contact with the wastewater.
The Signs and Causes of Failing Systems
- Experiencing Slow draining showers and toilets.
- pooling over the drain field.
- If there is an effluent filter in your system it may need cleaned.
- Roots intrusion in the lines
- too much water running into the system or elevated groundwater
- heavy vehicles driving over drain field causing excessive soil compaction.
- improper installation, excessive slopes, fracture in the bedrock, or a cut is made too close to the system it could require relocation of the drain field.
- odors caused by weather conditions can temporarily prevent proper odor dispersion
Septic System Maintenance
A properly designed and constructed septic system and drain field require regular maintenance every 3-5 years depending on your living situation and life style.
Don’t flush the following:
- Semi/non-biodegraded able items
- Kitty litter
- Disposable diapers, disposable wipes
- Feminine hygiene products
- Large amounts of bleach, or lye
- Motor oil
- Water softener brine
- Have a water filtration don’t add chemicals; sodium hydroxide or potassium hydroxide can cause sludge to drain into the leach field

