Tennessee Septic System Regulations

A properly designed septic system in Tennessee will provide years of trouble free service. An improperly designed one will cause nightmares in a week. In an effort to prevent this, the State of Tennessee has regulations and restrictions that must be adhered to even before a septic system is even installed, since nobody likes to wake up in the morning to the smell of effluent bubbling to the surface.

A properly designed septic system will not harm this field

Application For Permit Requirement

According to the state of Tennessee Department of Environment and Conservation, before a septic system is installed, an Application for a Septic Permit is required. The permit is obtained at your local municipality's building or code enforcement department. When you apply for a permit, an entire series of actions is undertaken. First, a qualified geologist or civil engineer surveys the site, runs a percolation test (a test to determine suitability of the soil), and designs the system. If the land will not support a septic system, the building department may offer guidance as to what options are available.

Water Table Restriction

There is a water table restriction that will prevent the issuance of a permit. First, the natural water table must be at least 4 feet below the surface of the leach field. This means that if the leach pipes are buried, for example, 3 feet below the surface, then the water table must be 4 feet below that, or 7 feet below grade (top of the field).

Lot Size Restriction

There is a lot size restriction as well. The lot must be sufficiently big enough to support a leach field, and have enough area available for a duplicate leach field, if another field has to be installed later on. Without this area requirement, a permit for installation cannot be issued.

Grade Slope Restriction

If the slope of the grade is 30% (1 foot of drop per every 3 feet of run), and the possibility exists of effluent bubbling to the surface, then a permit cannot be issued. For slopes 50% (1 foot of drop per every foot of run)or greater, no septic system is permitted. The Geologist or Civil Engineer doing the testing will issue a final determination on this.

Public Sewer Restriction

If there is a public sewage system available to be tied into, then the State of Tennessee will not issue a permit for a septic system. There are no exceptions to this regulation.

references & resources