Septic System Installation
About Installing Septic Systems
If you have not begun construction of your house you will want to give careful consideration to the placement of your home on your property. A home that is to be built on sloping ground would be best sited above the proposed absorption field. When this is not possible or ascetically desirable, you will almost always need to add a pump and an additional holding tank to your system in order to move the effulent to the higher absorption field. Most regulations require conventional absorption field to be located at least 100 feet from your property line, though this requirement will vary by locality. Single family homes sited on 10 or more acres may be able to avoid the need for permits but will still need to comply with state and local construction standards and will need to be at least 100 feet from the property line.
Once the homesite has been situated, you will need to decide on the type of septic system you will be installing. Generally, your choices are between conventional gravity operated systems and aerobic systems. Depending on environmental factors and population density you may not have a choice. Many localities now require aerobic systems for almost all new houses. Even in situations where a conventional system has been operating for many years, once the system fails, you may be required to install an aerobic system. Aerobic systems allow for the installation of an on-site sewage disposal system in situations where you would not otherwise be allowed to install a septic system at all. In North Texas there is a strong trend on the part of permitting agencies to require the installation of aerobic systems in most situations. A strong plus for aerobic systems is the reduced potetial for environmental impact.
Evaluating Your Site
To determine if you will be required to install an aerobic system and to determine the size of your storage tanks and absorption field, characteristics of your soil will need to be evaluated by a professional engineer. The engineer will be assessing your soil's ability to cleanly process the waste water that flows from your absorption field. Typically he or she will be looking at the proposed absorption field's proneness to flooding or ponding, depth to bedrock or cemented pan, depth to the highwater table, the ability of the soil to permeate or release water, density of large stones, and slope. To get this information the engineer will have several holes dug in the proposed absorption field and will run tests. This information will be used to determine if an aerobic system is required or if you can install a conventional system. If a conventional system is authorized, the engineer will evaluate the number of bedrooms in the proposed floorplan and will use this information together with the soil characteristic data to determine the size of the tanks and absorption field that needs to be installed.
Getting A Permit To Install A Septic SystemYou, your builder, or your septic installation contractor will need to apply for a permit. Typically these are issued by authorized permitting agencies of the state. In most states authorized permitting agencies are at the county level, often at the County Board of Health. In localites where aerobic systems are virtually universally required, you may be required to personally file the permit application. This is because you will be personally involved in running an active waste treatment plant and the local authorities want to make certain that you understand the maintence steps you will need to perform to keep your plant operating effectively. The typical application package will include the results of the professional engineer's site evaluation, a property plan showing location of the proposed dwelling, driveway, sewage lines, tanks, and absorption field, and any ponds, tanks or adjacent lakes. The application will also require a floor plan for the site, indicating rooms, closets, and total heated/air conditioned floorspace. It will also include several copies of the proposed design of the septic sytem and a map showing the property location. There will probably also be a requirement for a floodplain certificate, and the identification of a suitable second absorption field, should the initial absorption field fail at some future time and need to be replaced.
Permit Acceptance or Modification
Your local permitting agency will review your permit and determine if the proposed design meets local codes and regulations. If not, the application will be disappoved and you will be notified about any required design changes. In some instances you may be required to change from a proposed conventional system to an aerobic system. In these instances you will be required to resubmit your application. An additional application fee may also be required.
Septic System Construction
Once the septic construction permit has been issued, construction may begin. Usually the regulating authority will require that all or part of the construction be performed by a certified septic contractor. Typically your system will need to pass three separate inspections: before construction begins, after the absorption field has been excavated but before it has been covered over, and at least 5 days before the completed system is to be placed into operation.