Septic Systems

Septic System Care

Why do we need Septic Systems?

The purpose of sewage treatment is to remove solids, organic matter, nutrients, and disease-causing organisms, leaving effluent (or treated sewage) that is suitable and safe for release into the environment. If properly designed, constructed, and maintained, septic systems (or onsite sewage disposal systems) are an effective way to treat household wastewater in areas without access to sanitary sewers. A failing septic system can leak raw sewage into the environment and can pose a serious health risk to your family and neighbors and have negative impacts on groundwater and nearby streams, rivers, and lakes.

What is Raw Sewage?

Everything that you flush down the toilet, that goes down the kitchen sink, laundry, and bathroom sink, etc.
Contains human waste, toilet paper, but also unwanted things like wipes, feminine hygiene products, etc.
Typically contains viruses, bacteria, and microorganisms, all of which can be harmful to human health

What is a septic system and how does is work?

Learn more about septic systems in this video by Buckingham Realty. (Federal and State building codes and requirements in the US could be different than what is stated in video.)

Four main components of a septic system:

A pipe leaving your home that carries wastewater to your tank
A septic tank that is buried and watertight, where specific bacteria begin to break down the materials in wastewater
A drainfield where wastewater exits through drainpipes and into the soil for further breakdown
The soil, where different bacteria help to treat contamination from your wastewater as it works its way into the groundwater

Download A Kentucky Homeowner's Guide to Septic Systems here.

Bluegrass Greensource does have hard copies of this document while supplies last. Email lindsie@bggreensource.org for more information.

It is recommended to pump a septic tank every 3-5 years!

Why do I need to pump out my septic tank?

Up to 60% of the solids retained in the tank decompose; the remainder accumulate in the tank. Over time there is a build up of solids in the bottom of the tank as well as the scum layer on the top, so the liquid layer gets smaller. This will decrease the retention time, which increases the amount of solids reaching the lateral field. This leads to failure or the backing up of sewage into the house due to clogged lateral lines.

What causes septic systems to fail?

Septic tank or drain field additives (chemical and biological) that claim to extend system life can actually ruin your system by throwing it out of balance, and are not approved. Instead of spending money on additives that don’t help and do harm, spend the money every 5 years to pump out your septic tank.
The tank can crack and leak or the baffles can deteriorate, crack, break or fall off.
Diapers, toys, wipes, and garbage that find their way into toilets risk clogging drain/distribution piping and tank filters.
Vehicle traffic and tree roots can damage the lateral drain field, and collapse the outdoor waste piping.
Compacted soils, grease and excess floating solids, and building or paving on the leach field can all clog or compress the soils around the field and inhibit evaporation and soil absorption, which leads to failure.

Septic System Dos and Don'ts:

Student Activity for Septic Systems:

Make a Model Septic System

This activity lets students demonstrate the basic concepts of how a septic tank and leach field work. It can be used as a basic introduction to where water goes after being flushed or as a beginning activity for a series of more in-depth activities.

The Septic Tank holds household wastewater, allowing bacterial action to separate sewage into three distinct layers in the tank; clarified effluent, settled sludge, and floating scum. The tank removes solids by holding the wastewater in the tank for 24-72 hours, allowing heavier solids to settle as sludge and the lighter particles to form scum at the top.

Materials Needed:

2 clear glasses or 2 glass jars
sand
paper towel
potting soil
food coloring
flexible straw
tiny pieces of paper
masking tape
sharpie

Step 1: Label the glasses or jars.

One is the septic tank and the other is the leachfield.

Step 2: Prepair the septic tank.

Fill half the glass or jar with water, 1/4 a cup of sand, 3 drops of food coloring, and tiny pieces of shredded paper.

Step 3: Prepare the leachfield.

Add alternating layers, around two of each, of sand and soil. Divide each layer with a piece of the paper towel. Gently pour one cup of water over the leach field.

Step 4: Set up the model.

Find a book, a game or something to elevate the septic tank.

Step 5: Elevate the Septic Tank

Once you are set up, shake or stir the septic tank and allow it to settle.

Step 6: Prepare the leach field.

Set up the leachfield directly below the septic tank. Fill the straw with water, holding the water inside at both ends.

Step 7: Create a siphon. I added an extender piece to my straw, so the only part of the straw bending was the flexible part.

Insert the straw into the waste water and then into the leachfield.

Step 8: Make Observations

Watch what happens to material in the septic tank.

Step 9: Record your data.

What settled to the bottom? What stayed on the surface? Does this reflect a septic tank?

This work was funded in part by a grant from the U.S. Environmental Protection Agency under §319(h) of the Clean Water Act.

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