Aerobic or Anerobic

Aerobic or Anaerobic – Which is Best for Me?

Soil and site conditions ultimately determine what the best type of septic system is to be installed and allowed by the permitting authority.

Both Anaerobic (conventional) and Aerobic wastewater systems are effective when properly maintained.   Some counties in Texas require installation of aerobic systems for new home construction and septic system replacement.


  • Uses bacteria that need dissolved oxygen to live and prosper to digest the wastewater solids very rapidly, inside the tank.
  • Treated water that is now harmless to plant or animal life leaves the tank and can be sprayed or drip emitter fed to the land.
  • The treated, odorless water does not damage the ecology, and in-tank objectionable odors are easy to control.
  • Pumping is recommended to help avoid overwhelming the system and economy of operation.

On rocky terrain, the cost of installing a new aerobic septic system is lower than an anaerobic soil substitution system that will require building a leech field, provided the homeowner has enough land on which to do so.

If the homeowner has a lot of land, with well-drained soil, initial installation of an anaerobic system might cost less, but the maintenance of an anaerobic (leech field) system could be higher if the soil becomes overwhelmed if it unable to handle the load (terrain turned wet or marshy, or it was subjected to excessive organic loading).


  • Uses bacteria that live with little or no oxygen to treat the wastewater for distribution in a sub surface drain field.
  • The drain field relies on the microbes in the soil to treat the wastewater.
  • Objectionable odors can be controlled. If used beyond design limitations, repairs might be necessary for continued good performance.
  • Pumping is recommended to help avoid overwhelming the system and economy of operation.

In some areas, installation of a new Anaerobic (Conventional) septic system is not allowed.

Although components are less expensive for an anaerobic system, it is much more labor intensive to install a anaerobic system.

The drain field should be located far from any trees to minimize root infiltration inside the drain field lateral lines.

The soil under and that covers the drain field, facilitates in the treatment of the wastewater.

An Anaerobic (Conventional) system is less expensive than an aerobic system.

Contact Benchmark Wastewater on installation of an anaerobic or aerobic system.