What Septic Drain Fields Do – A Thankless Job

Learn how your septic drain field works, plus important upkeep tips!


Ah, septic systems – as revolting as they seem, they are actually a helpful invention, keeping waste out of sight and out of mind. Most of the time, they work as they should and have little to no issues. As with any system, however, failure can occur, particularly with septic drain fields. Learning how your septic system works as a whole can help you recognize the warning signs of a breakdown so you can deal with it in a timely manner.


What role does the drain field play in a septic system?

Septic drain fields have one key job: to filter wastewater! The EPA (United States Environmental Protection Agency) does a great job of explaining how a drain field works in conjunction with a septic system:

  1. “All water runs out of your house from one main drainage pipe into a septic tank.
  2. The septic tank is a buried, water-tight container usually made of concrete, fiberglass, or polyethylene. Its job is to hold the wastewater long enough to allow solids to settle down to the bottom forming sludge, while the oil and grease floats to the top as scum.
    Compartments and a T-shaped outlet prevent the sludge and scum from leaving the tank and traveling into the drain field area.
  3. The liquid wastewater (effluent) then exits the tank into the drain field.
  4. The drain field is a shallow, covered, excavation made in unsaturated soil. Pretreated wastewater is discharged through piping onto porous surfaces that allow wastewater to filter through the soil. The soil accepts, treats, and disperses wastewater as it percolates through the soil, ultimately discharging to groundwater.If the drain field is overloaded with too much liquid, it can flood, causing sewage to flow to the ground surface or create backups in toilets and sinks.
  5. Finally, the wastewater percolates into the soil, naturally removing harmful coliform bacteria, viruses and nutrients. Coliform bacteria is a group of bacteria predominantly inhabiting the intestines of humans or other warm-blooded animals. It is an indicator of human fecal contamination.”

How to maintain your septic drain field

In order to maximize the effectiveness of your septic drain field, implement these helpful maintenance steps:

  • Keep a lookout for wet spots (indicative of flow problems)
  • Take note of any foul odors (indicative of backed up system)
  • Check septic tank fill level (once a year)
  • Pump septic tank waste (approx. every 3-5 years)
  • Test for presence of bacteria and dangerous chemicals (a couple times a year)
  • Get a professional to inspect your system (at least every 3 years)


Closing thoughts

The septic drain field plays a vital role in your septic system! It filters and removes harmful substances out of the septic water and eliminates unpleasant odors. When the drain field isn’t working properly, it’s likely you’ll notice and fully appreciate what it does! Whether you need a drain field installed or you’d simply like to make sure your septic drain field is doing its job, call Pickle Septic for answers to all of your septic system needs!

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