Septic Problems - Failing Septic Tank

A septic tank may fail for any of the following reasons:

Size. Some older tanks may be undersized relative to current water use.  Current design standards often require larger septic tanks than standard practice from 30-years ago.  The larger septic tanks provide more reliable treatment of sewage prior to effluent disposal into the ground. 

Structural deficiencies.  The most common form of septic tank is a reinforced concrete box.  The septic tank may be cracked or have significant deterioration of the concrete such that there is risk of the tank collapsing or caving in. ...more

Excessive corrosion of the tank concrete can also lead to cracking.  Sewer gases tend to be highly corrosive and can lead to tank failure over time.  ...more

Leaking septic tank.  Leaking can occur through bottom or side cracks, deteriorated concrete, seam leaks, or leaks around the inlet and outlet pipes. ...more

High groundwater or flooding.  These events can result in excessive flow through the septic tank that may wash out fats and settled solids. ...more

Damaged or missing baffles.  Inlet and outlet baffles are critical to the proper function of a septic tank to remove fats, oils and grease as well as settleable solids. ...more

Refer to Septic Basics - Septic Tanks for additional information regarding septic tank baffles.