A home that does not have access to a municipal sewage system must treat sewage on site with a septic system. Since a septic system is buried entirely underground, it is not something the average person thinks about. While most people would be happier never thinking about septic systems at all, a little knowledge can save a lot of money.

Home buyers should be aware that septic systems often fail when a new family moves in. If the old owners had no children, or if their children moved away and the new owners have a family, the new owners will place increased demands on the septic system. A system that held together for years can fail under a new load. But if the system starts in good condition, a problem is unlikely to arise.

Since the septic system is entirely buried, it is not inspected during a home inspection. A home buyer will have to make special arrangements to have the system inspected.

Components of the System

Septic systems can be complicated, but in essence they all have two distinct parts: the septic tank and the leaching field.

Septic Tank: Sewage flows into the septic tank. The solids sink to the bottom and the oils float to the top. A special baffle ensures that the remaining liquid flows into the leaching field, leaving the solids and oils behind.

Some of the solids decompose over time but the septic tank will slowly fill up and eventually require pumping out. Typically, a tank is pumped every three years, but pumping timing also depends on the size of the family using the tank. If a home owner waits too long between pumpings, the leaching field could be damaged.

Leaching Field: Liquid effluent from the septic tank flows into a series of perforated pipes that "leaks" the effluent into the surrounding soil. As the effluent sinks into the soil, naturally-occurring bacterial action and filtration render the effluent harmless.

The final destination of the liquid effluent is the ground water. If you draw your drinking water from the ground water. If you draw your drinking water from the ground water, it is in your best interest to ensure the entire septic system works optimally.

Importance Maintenance Tips:

  • Do not drive cars or truck over the leaching field
  • Do not plant trees or shrubs in the leaching field
  • Have the system inspected periodically and pumped out as needed
  • Do not flush the following: cooking grease or unwanted chemicals, such as cleaners and solvents

Warning Signs of Failing Septic System

  • Foul smells in the vicinity of the leaching field
  • A Soggy leaching field
  • Green strips of grass or depression lines outlining the leach pipes
  • Waste water backing up into the house

What to ask the Seller

  • List any problems with the system
  • Location of the septic tank and leaching field
  • Date of the last septic tank pump-out and the name of the company that does the pumping
  • List of repairs or modifications to the system

The septic system is critical system. Complete replacement of a septic system can be expensive. For this reason, hiring an expert to inspect it will expedite problem detection and corrective action before a major problem occurs. The inspector can also give an estimate of the pumping frequency required for your system based on family size.


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