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What is an onsite wastewater system (aka septic system)?

September 19, 2019

Septic system illustrationAs part of SepticSmart Week (September 16-20), MI Environment is highlighting how homeowners and communities can properly care for and maintain their septic systems.

Where does it go? You know, when you flush. Well, it depends on where you live. If your home's plumbing is connected to a community wastewater system, then it goes to your local wastewater treatment plant. And if it isn't, then you have your own onsite wastewater system, also known as a septic system -- like 25% of Michigan's population. A septic system is underground, and basically out of sight. But it can't be out of mind or you may have expensive reminders of how important it is to understand and maintain your septic system.

All septic systems, either municipal or single-family septic systems include:

  • Collection system 
  • Treatment components 
  • Dispersion into the environment

In this example of a septic system:

  • No. 1 is the building, sewer or collection system leading to
  • No. 2, the septic tank which is the first step in the treatment system followed by
  • No. 3 and 4, the drainfield where the final treatment and dispersal into the environment happens.

The septic tank (see illustration) holds wastewater long enough for solids to settle to the bottom and fats, oils, and greases float to the top. This collection system is a key and primary component that needs maintenance.

The septic system takes your wastewater, treats it, and returns it to the environment near its initial point of use -- which means you're not using additional resources to transport that wastewater miles away for treatment.

By properly maintaining septic systems, residents protect both people and the environment.

To learn more about septic systems, please visit the Onsite Wastewater webpage.

For more about SepticSmart Week, read yesterday's MI Environment article.


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