Homeowners Guide to Septic Tank Systems

Information provided by:

Environmental Health-Fayette County
Robert Kurbes (770) 631-0743, ext. 150

Environmental Health-Georgia
Georgia Department of Human Resources
47 Trinity Avenue, S.W.
Atlanta, Georgia 30334

What is a Septic Tank System?

A septic tank system consists of two components:

  1. The septic tank is an underground watertight container, almost always constructed of concrete, and is built to receive sewage and retain the liquid portion for approximately 24 hours. The tank has three functions: First, it acts as a settling chamber to allow solids to settle to the tank bottom; second, the tank serves as a digestion chamber to allow some biological treatment; and third, the tank becomes a storage vault for solids until removed.
  2. The tile absorption field (nitrification field) is the second and probably the most critical part of the septic tank system. It consists of a trench, or system of trenches, with gravel or crushed stone and jointed tile or perforated pipe to receive the liquid sewage after treatment in the septic tank and to distribute this liquid to the soil for absorption and final biological treatment.

Septic Tank System Installation

To protect the public health dangers of improper sewage disposal practices, state regulations have been adopted. The regulations are designed to help insure that when a septic tank system is used, it will be constructed to meet appropriate standards, of sufficient size to handle the anticipated waste load, and that the soil is suitable for absorption of sewage. These regulations require that a permit to construct a septic tank system be obtained from the county health department. A septic tank system may not be covered with earth until an inspection is made and approval is given by the county health department sanitation. Remember that a septic tank system cannot be safely installed on all lots or building sites. Some lots or building sites are unsuitable because of the type of soil, terrain (too steep, too low or wet, etc.), size, ground water, rock, or other factors which would interfere with proper operation of the system.

Although one usually wants to keep all the trees and shrubs possible on his lot, remember that the roots of trees and shrubs growing near the septic tank, system may infiltrate the absorption trenches and block the flow of sewage. It is advisable to remove trees and shrubs growing over the trenches or near the septic tank system.

Care of Your Septic Tank System

A septic tank system requires prudent usage and maintenance to insure its best performance. Here are some tips:

  1. Only household waste and toilet tissue should be disposed of in a septic tank system. Keep all kitchen greases out of the system.
  2. Any leaks that develop in the plumbing fixtures should be immediately corrected. A leaking faucet or toilet tank, no matter how small the leak, will eventually result in complete saturation and failure of the absorption field.
  3. A septic tank needs periodic cleaning or pumping out of the accumulated solids. If the solids are allowed to build up in the tank to a point that they begin to pass out of the tank into the soil absorption network, the soil will soon become clogged with the solids, resulting in failure of the system. If this happens, costly repairs will have to be made before the system will again function properly.
    The frequency of tank cleaning or pumping is hard to determine as it depends on many factors and varies with different families. The only sure way to determine the need for service is to open the tank periodically and inspect it to determine the accumulation of solids, but most homeowners will not do this when it is needed. A good rule of thumb would be to have the septic tank pumped out every 3 to 5 years. This should provide a margin of safety, but remember the most accurate way to determine the need for service is to inspect the tank contents on a yearly basis. When you decide to pump out the tank, contact the county health department for a list of sewage removal contractors who have been approved as having the proper equipment to do the job and an approved site to dispose of this offensive waste.
  4. Automobiles and other heavy vehicles should not be allowed over the septic tank system. This causes excessive compaction and actual structural damage to septic tanks and tile absorption field. A sketch of your septic tank system can usually be obtained from your county health department to aid you in knowing the location of all parts of the system. This can be helpful in case of problems with the system or when the tank is cleaned. 
  5. No presently known chemical, yeast, bacteria, enzyme, or other additive product will improve the operation or life expectancy of a septic tank system.

Buyer Beware

If you are about to purchase a lot to construct a home in an area which is not served by a public sewerage system, contact the county health department to find out if that lot has been approved for development using a septic tank system. They may already have information on this property, but if not, an evaluation can be made, and the owner may have to arrange for soil tests to be made by an engineer or surveyor before a decision can be made on its suitability.

Tips on Water Conservation

Studies indicate that the average household can reduce water consumption by 15 to 20% by using water-conserving toilets and showerheads. The toilets are readily available from most major manufacturers at no additional cost over conventional toilets. These are ideal for new construction as well as replacement units. The showerhead water conserver can be attached to existing shower equipment at little cost and reduces the amount of water used by about 50%. The toilets reduce water usage from over 5 gallons per flush to 3% gallons. The benefits from water conservation are many, but here are just a few: 

  1. Cost of water. Water rates are likely to continue to increase in the future. 
  2. Cost of heating water. 
  3. Cost of pumping water (well pump). 
  4. Reduced load on septic tank system 
  5. Reduction in charge for disposal of sewage in city system 
  6. Reduced load on sewer lines, sewage treatment plants, etc.

We all need to practice water conservation if we are to continue to have plentiful supplies of good water for use in our homes and industries.