August 2002 Edition

Septic Tank Systems

We are buying an older home with a septic tank. We've never had a septic system before and are a little uneasy. Are they as good as a public sewer?
Yes, they are just as good. I have one with my new home and it will save me thousands of dollars in sewage fees over my lifetime.


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
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.
To protect the public health from the dangers of improper sewage disposal practices, state regulations have been adopted. The regulations are designed to help insure 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 sanitarian.


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.
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 and hygiene items 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 property.
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 7 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.
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.

Source: Georgia Department of Human Resources

If you have a question, change of address, comment, home tip or would like to send Home Tips to your clients, send your letter to Home Tips, Christian Building Inspectors, Inc., 3697 Habersham Lane, Duluth, Georgia 30096. You can E-Mail your questions to us at We reserve the right to edit questions for length.

Quote Of The Month

"You never know when you're making a memory."

- Rickie Lee Jones

A Tip Of The Hat To:

Donna Irwin

Coldwell Banker/Buckhead Brokers

4790 Sugarloaf Pkwy, Suite 200

Lawrenceville, Georgia 30044

**** Thank You****