Tuesday, September 16, 2014   

On-Site Wastewater Systems: General Information

The following is general information about septic systems. See bottom of this page for links to additional information.

Investigate Before You Invest

North Carolina Laws and Rules require local health departments to evaluate a prospective site for a new septic tank system upon submission of a valid application from the property owner or his/her legal representative. Often the Public refers to this as a "Perk Test". The Perk Test is no longer used by any Health Department to determine if a property is suitable for a septic tank system permit. Instead, a site evaluation is completed to evaluate such factors as the landscape and topography position, soil characteristics (sand, silt, clay composition), soil wetness (based on soil color), soil depth, restrictive horizons (hard-pans), and available space for the proposed septic tank system and repair area if required.

Unfortunately, many sites in Brunswick County have severe limitations for the proper functioning of a septic tank system. For some marginal sites a permit can be issued with specified site modifications. An example is adding suitable fill soil (referred to as a mound system). However, this option is not always available. No one should add fill to their lots in hopes of getting a septic tank system permit prior to having their lot evaluated. The site evaluation factors discussed above are considered in evaluating what options may be available for whether or not a permit can be issued with site modifications or a different type of septic tank system. North Carolina Laws and Rules require Health Department to advise applicants of any option that may exist for a site. The Public also has Appeal Rights that are set by Law.

For people planning to relocate a manufactured home to a lot with an existing septic tank system it is also wise to make sure the existing septic tank system is designed (large enough) and properly functioning to accommodate their new home. Septic tanks and the drainfield are sized according to the number of bedrooms in the house. Some sites are unsuitable for the upgrade of the septic tank system due to North Carolina Laws and Rules. Thus, before you sign a contract, it is wise to make sure you can obtain a septic tank system permit. You may need to also check with other regulatory agencies such as Building Inspection Departments and Zoning Authorities.

Effluent Filters

North Carolina State Laws and Rules for Sewage Treatment and Disposal Systems require that effluent filters be installed for all new septic system.

The purpose of an approved effluent filter is to trap solids and some of the suspended solids so they do not flow out of the septic tanks. This should extend the "life" of your drainfield by minimizing premature clogging of the drainlines by solids. If solids clog the drainfield, wastewater cannot percolate into the soil, resulting in sewage breaking out to the ground surface. Once sewage has broken out on the ground surface a costly septic system repair will be needed.

Preventing Costly Repairs

To prevent costly septic system repairs, a septic tank system should be routinely maintained. Periodically, you should have a licensed septic tank "pumper" (see your local phone directory) pump your septic tank to remove solids that have accumulated. The maintenance is critical. How often a septic tank needs to be pumped depends on the volume of the tanks and the number of occupants in the home. A general rule is to pump it every 3 to 5 years.

The effluent filter also will have to be periodically cleaned and then returned to the filter retainer, which is installed at the septic tank outlet. The frequency of how often the effluent filters will need to be cleaned will also vary. If wastewater from you house plumbing fixtures begin to drain slowly you may wish to check or have a contractor check to see if the effluent filter needs cleaning. Another general recommendation is when the filter is cleaned it is a good time to check to see if the septic tank should be pumped.

Limiting the use of kitchen garbage grinders will also reduce solids from entering the septic tank.

Septic System DOs And DON'Ts

All wastewater from the home must be plumbed to the septic tank. This includes all sink, bath, shower, toilet, washing machine, dishwasher, etc.

  • Do keep roof drains, and other rain water or surface water drainage systems away from the septic tank and system drainfield.
  • Do establish a good grass cover for the drainfield to help prevent erosion and help remove excess water.
  • Do not use caustic drain openers for a clogged drain. These can kill the useful bacteria necessary for proper functioning of the septic system.
  • Never use your septic tank system as a trash can. Do not dispose of grease, disposable diapers, kitty litter, paint, tampons, condoms, oven cleaners, cigarettes, etc. into the septic system.
    Putting these materials in your system may contribute to septic tank system problems necessitating possible expensive repairs for you.
  • Do not drive, pave, or build any structures over the septic tank system area including the reserved repair area if required.
  • Do not plant trees or shrubbery in the drainfield area because roots will damage the septic tank system.

Furthermore, commercial septic tank system additives are generally not needed.

With a minimum amount of maintenance care your septic tank system should provide years of trouble free operation. If you abuse or fail to maintain your septic tank system it is highly likely you will sooner or later have a septic system failure.


More Information

For a wealth more information about septic systems, see North Carolina Department Of Environment And Natural Resources (DENR), On-site Wastewater Section, website.