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How It Works

Ever wonder how a septic system works, or why we need them at all? Here is a quick overview of what a septic system is and how it works for your home or business:

A properly installed septic system is a good way to treat wastewater and to protect groundwater quality when local town or city sewer service is not available.

Waste from toilets, sinks, washing machines and showers enters the septic tank, which is a holding tank generally made of pre-cast concrete or fiberglass and is sized according to the estimated wastewater flow from a given-sized residence or business.

The septic tank separates the wastewater into three general components — solids or “sludge”, floatables or the “scum layer”, and a zone of relatively clear water.  Bacteria perform the first treatment of the wastewater, generating gas that is vented through the vent stack of the building’s plumbing and breaking the solids into a liquid form.

From the septic tank, the liquid portion of the wastewater flows into the drainfield, which is generally a series of perforated pipes or slotted panels that are usually surrounded by a layer of gravel, tire chips, or other lightweight materials such as styrofoam pieces.  The drainfield provides secondary treatment of the sewage by allowing bacteria to continue deactivating the disease germs that remain in the wastewater.  The drainfield also provides filtration of the wastewater as gravity draws the water downwards through the soil layers.  In addition, evaporation of water occurs through the layer of soil covering the drainfield.

In some areas where soil types such as clay layers or bedrock exist, or in areas where there is a shallow seasonal high water table, septic systems must be elevated above the ground surface.  This ensures the wastewater has sufficient permeable or unsaturated soil in order to provide adequate filtration before the remaining wastewater reaches the groundwater table and the underlying aquifer.

Whether you are looking for a full septic system installation or repair or maintenance on an existing system, Mid State Sewerage can help. We offer professional quality installation and maintenace services for jobs of all sizes. Don’t hesitate, contact us today for your free estimate!