Leach Field & Leach Field Problems

Septic Drain Field

Septic Drain fields, also Most commonly called Soil treatment area(STA), or the old term Leach Field. Are subsurface wastewater disposal systems used to remove contaminants and impurities from the liquid discharged by a septic system.

There are several different types of STA’s in use today. The most commonly used is a series of four-inch diameter Perforated PVC pipe in cased in two-to-three foot wide stone filled trenches, with porous material(like gravel or sand) around and underneath the pipe to promote drainage and reduces root growth near the pipeline. A minimum topsoil placement is covered over the porous material to protect contact with wastewater  and reduce infiltration from rain and snow.

Septic Drain field/leach Field

Cut-away of Septic Drain field/leach Field









Septic Drain field/leach Field

Cross Section of Septic Drain field/leach Field

What if I am having problems with my STA/leach field?

wastewater ponding on top of leach filed

Symptoms of trouble:

  1. toilets won’t flush, or flush slowly
  2. wet on top of the leach field(pictured above)
  3. water standing in inspection or vent pipe from leach field
  4. water or sewage backing up in the house

How do I know if this is a STA/leach field problem or a drainage problem?

You can call your septic company or if you are able, handy, check the level of liquid in your tank.

Using your wife’s favorite shovel, pry up the tank lid or lids. The level of the tank should be down where the inlet comes in from the house or on the outlet where the effluent leaves the tank for the leach field. This is about 10 – 12 inches down from the top of the tank. If the level is normal, (at the bottom of the inlet pipe), you have a clogged line from the house to the tank.  Call us for recommendations if plumbing service is needed!!

If this level is up to the lid, or overflowing you have an obstructed line to the leach field or a problem with the drainage in the leach field.

Problems with leach fields are a result of many different reasons.

  1. Age of leach field
  2. Engineering or installation problems
  3. Not pumping tank often enough
  4. Compaction problems from parking cars, livestock on top of leach field lateral lines
  5. Spring runoff of water can flood leach fields.
  6. Too much water usage.  Hydraulically overloading the system.  This causes a bio mat to build up in the leach field and the bio mat starts restricting the water absorption in the leach field

If you are on a septic system and your leach field is not draining the way it should, you can replace the leach field if you have room on your property or, we have some alternatives


We have a Terralift machine. We use this over the leach field surface.  The machine punches a probe down in the ground 6 ft ., then a compressor injects air and polystyrene beads. This fractures the ground and the beads opening up paths for the water to leach back in to the ground. We have had good results with this process.  Call us to schedule an appointment for us to come out for an evaluation  also check out the teralift on  www.terraliftinternational.com


Bio-remediation is a system we also use which has been successful  It is a specially formulated bacteria we use on a problem field.  Once injected in the system, it goes after eating up the bio mat that has accumulated.   Go to www.propump.com  or we will send you a booklet on the process.

Contact us for a FREE Leach Field evaluation