Managing On-lot Septic Systems

On-lot septic systems typically consist of a treatment tank and a soil absorption area which is commonly called a leach field or drainfield.
Managing On-lot Septic Systems - Articles


Photo: Amy Galford

The treatment tank removes and partially degrades solids while the soil under the absorption area absorbs and cleans up the liquid effluent from the treatment tank.

Properly designed on-lot septic systems provide adequate treatment and disposal of liquid household wastes. In spite of the efforts of regulators and contractors to properly design and size these systems, onlot systems may still malfunction. A malfunctioning on-lot system results in sewage backup in the household, and untreated sewage causing smelly, unhealthy wet spots in your yard and possibly contaminating groundwater. Although contaminated groundwater may be out of sight, it is important since nearby drinking water wells, possibly even your own, and nearby streams can become contaminated. Assuming your on-lot system was properly designed and sited, malfunctioning of onlot sewage systems usually occurs for one of four reasons: poor installation, hydraulic overloading, biological overloading or lack of maintenance.

Heavy equipment should never be permitted in the absorption area during installation or on the absorption area after you start using it. This equipment can compact the absorption area, or break pipes within the aggregate layer. Also, if surface water runoff is not diverted away from the absorption area, it may overload the system.

A common reason that septic systems fail is when the soil is not capable of absorbing all of the wastewater delivered to it by the sewage system, called hydraulic overloading, and the drainfield becomes clogged due to the development of a slime layer or biomat created as a result of persistent wet conditions in the absorption area.

When your septic system begins to give you trouble, it's time for two things; first have the treatment tank pumped, and second is to find a way, such as a family vacation, that will reduce water usage in the home to zero for a short time. Actually, you should have your septic tank pumped every two to three years regardless of whether your septic system is giving you problems or not. This will limit the build-up of solids in the septic tank. When solids get too deep in the septic tank, they can be carried to the absorption area with the septic tank effluent.

So what can you do to prevent problems?

  • Take every opportunity to conserve water in the home.
  • Do not use, or at least severely curtail, the use of a garbage disposal in the home.
  • Do not flush anything but water, wastewater, human waste and toilet paper into your septic system. Anything else has a very high likelihood of causing a back up and failure of your system!
  • Chemical or biological enzyme additives are not recommended.
  • Do not add harsh chemical cleaners to your septic system.
  • Do not plant deep-rooted plants or trees over or near the absorption area.
  • You can also have the system inspected by an experienced professional every few years.