How does a Septic Tank Work?

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.

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.

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 (Onsite Sewage Disposal System)?

1. A pipe leaving your home that carries wastewater to your tank

2. A septic tank that is buried and watertight, where specific bacteria begin to break down the materials in wastewater

3. A drain field where wastewater exits through drainpipes and into the soil for further breakdown

4. The soil, where different bacteria help to treat contamination from your wastewater as it works its way into the groundwater

If properly designed, constructed, and maintained, septic systems are an effective way to treat household wastewater in areas without access to sanitary sewers.

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.

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

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 3 to 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, 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.

The DOs and DON’Ts of septic care:

  • DO have your septic system inspected annually by a licensed onsite professional, and arrange for your septic tank to be pumped every 3 to 5 years.
  • DO reduce or eliminate use of garbage disposals.
  • DO use water efficiently to avoid overloading the septic system. Repair leaky faucets or toilets. Keep showers short, wait to run washing machines and dishwashers until you have a full load, turn off water while brushing teeth, etc. Use high-efficiency fixtures.
  • DO direct downspouts, gutters, foundation drains, and surface waters away from your septic system.
  • DO use commercial cleaners and detergents in moderation. Try cleaning toilets, sinks, showers, and tubs with a mild detergent or baking soda.
  • DO check with your local county health department or onsite professional before allowing water softener backwash to enter your septic tank.
  • DO keep records of repairs, pumping, inspections, permits issued, and other system maintenance.
  • DO learn the location of your septic system. Keep a sketch of it with your maintenance record.
  • DO plant only grass over and near your septic system. Roots from trees or shrubs may clog and damage the drainfield.
  • DON’T put dental floss, feminine hygiene products, condoms, diapers, cotton swabs, cigarette butts, coffee grounds, cat litter, paper towels, paints, pesticides, or other hazardous chemicals into your system. Your septic system cannot function as a trash can.
  • DON’T use caustic drain openers for a clogged drain. Instead, use boiling water or a drain snake to open clogs.
  • DON’T add any treatments, chemicals, yeast, or other treatments to your system.
  • DON’T drive or park vehicles on any part of your septic system. Doing so can compact the soil in your drainfield or damage the pipes, tank, or other septic system components.
  • DON’T dig into your drainfield or build anything over it.
  • DON’T make or allow repairs to be made to your septic system without first contacting your local county health department inspector.

Check out our list of upcoming workshops and gain the tools to take better care of your septic system. By attending a workshop, you may learn if you’re eligible for financial assistance.