• Jodi Eberhardt

Understand Your Septic System

Understanding your system is essential to proper operation

and maintenance. The University of Minnesota publishes a "Know your Septic System Guide" and has information for septic system owners.

How it works:

The Septic Tank receives the wastewater from the

household plumbing. In the tank, the solids are separated

from the liquid. Here, naturally occurring bacteria decomposes

food particles and human waste and the remaining

solids settle to the bottom until they are pumped out on a

regular basis. The tank will have an inspection pipe for

monitoring of the tank and a manhole for access when

pumped. The size of the tank is based on the home’s

potential water use and types of appliances installed.

When the capacity of the tank is reached the excess liquid

flows, or is pumped, over into the drainfield.

The Soil Treatment System (drainfield), which is typically

a network of perforated pipes surrounded by small

rock and soil. The liquid, which contains pathogens (disease-

causing organisms), nutrients such as phosphorus,

and fine solids, is cleansed naturally by bacteria as it

percolates down through the soil. The design of the treatment

system (trench, mound, etc.) is based on the soil

conditions on your property, which must allow for at least

three feet of unsaturated soil for the wastewater to percolate

through for proper treatment. The correct type of

system needed for your property will be determined by a

state-licensed septic designer. Where gravity flow is not

enough to move the liquids from the tank to the soil

treatment system, pumps or lift stations are common—

this is typical with mound systems.

Who regulates?

The design, inspection, and installation of

septic systems are regulated by your county and must be

done by professionals licensed by the state. Lists of

licensed professionals and permits for septic system installation

can be obtained from the Planning & Zoning Office.

What records are required? A septic system must have a

“Certificate of Compliance” indicating it meets the county’s

SSTS and Wastewater Ordinance, sometimes referred to

as being “up-to-code.” A Certificate is good for five years

from the date of original installation and it must be

renewed every three years thereafter.

When are inspections required?

If you are applying for a

building permit for new construction, a compliant septic

system is required. A building permit for any addition to

current buildings, including a deck or garage—attached or

non-attached, requires a current Certificate of Compliance

for the septic system. If one is not on record or it is not

current, an inspection of the septic system will be required

and, if the system is found to be noncompliant, modification

or replacement of the system may be necessary

before a building permit is issued.


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