A Professional Onsite Wastewater
April 11, 2016
Septic System Efficiency
A septic system is a highly efficient, self-contained, underground wastewater
treatment system. Because septic systems treat and dispose of household
wastewater onsite, they are often more economical than centralized sewer systems
in rural areas where lot sizes are larger and houses are spaced widely apart.
Septic systems are also simple in design, which make them generally less
expensive to install and maintain. And by using natural processes to treat the
wastewater onsite, usually in a homeowner's backyard, septic systems don't
require the installation of miles of sewer lines, making them less disruptive to
A septic system consists of two main parts-a septic tank and a drainfield.
The septic tank is a watertight box, usually made of concrete or fiberglass,
with an inlet and outlet pipe. Wastewater flows from the home to the septic tank
through the sewer pipe. The septic tank treats the wastewater naturally by
holding it in the tank long enough for solids and liquids to separate. The
wastewater forms three layers inside the tank. Solids lighter than water (such
as greases and oils) float to the top forming a layer of scum. Solids heavier
than water settle at the bottom of the tank forming a layer of sludge. This
leaves a middle layer of partially clarified wastewater.
The Septic Tank
The layers of sludge and scum remain in the septic tank where bacteria found
naturally in the wastewater work to break the solids down. The sludge and scum
that cannot be broken down are retained in the tank until the tank is pumped.
The layer of clarified liquid flows from the septic tank to the drainfield or to
a distribution device, which helps to uniformly distribute the wastewater in the
drainfield. A standard drainfield (also known as a leachfield, disposal field,
or a soil absorption system) is a series of trenches or a bed lined with gravel
or course sand and buried one to three feet below the ground surface. Perforated
pipes or drain tiles run through the trenches to distribute the wastewater. The
drainfield treats the wastewater by allowing it to slowly trickle from the pipes
out into the gravel and down through the soil. The gravel and soil act as
Septic System Maintenance
If you own a septic system, it is important that it be properly maintained.
How often you need to pump the solids out of your septic tank depends on three
1. the number of people in your household;
2. the amount of wastewater generated (based on the
number of people in the household and the amount of water used); and,
3. the volume of solids in the wastewater (e.g., using a garbage disposal
will increase the amount of solids).
the Leach Field
Although your septic tank absorption field generally does not require
maintenance, you should adhere to the following rules to protect and prolong its
1. Do not drive over the absorption field with cars, trucks, or heavy equipment.
2. Do not plant trees or shrubbery in the absorption field area, because the roots can get into the lines and plug them.
3. Do not cover the absorption field with hard surfaces, such as concrete or asphalt. Grass is the best cover, because it will help prevent erosion and help remove excess water.
4. Do divert surface runoff water from roofs, patios, driveways, and other areas away from the absorption field.
Don't Flush It
Homeowners wanting to take good care of their septic systems should make note of the following items that should never be flushed down the drain or toilet. These items can overtax or destroy the biological digestion taking place within the system or clog pumps and pipes.
Take care not to flush the following:
hair combings, coffee grounds, dental floss, disposable diapers, or kitty litter, sanitary napkins, tampons, cigarette butts, or condoms, gauze bandages, fat, grease, or oil, paper towels, diaper wipes or handy wipes.and NEVER flush chemicals that could contaminate surface and groundwater, such as: paints, varnishes, thinners, waste oils, photographic solutions, or pesticides.