WHY DO WE HAVE THEM?
The mountainous and rocky terrain in much of the northeastern U.S. requires that houses be further apart. This makes public sewers prohibitively expensive.

HOW DO THEY WORK?
Wastewater and solids leave the house and enter the septic tank. There solids are held back for bacterial digestion and water is allowed to flow beyond to the leaching portion of the system.

The leaching system, which may be made of trenches, seepage pits or galleries allows waste water to reenter the earth.

HOW DO THEY FAIL?
Similar to most other house components, septic systems require routine maintenance. Also, certain repairs may be necessary from time to time to keep the septic system working properly. Leaching systems eventually become clogged with organics from age and use. This prevents them from percolating wastewater back into the earth at a reasonable rate. Wastewater surfacing in the yard usually results. The lifespan of a septic leaching system depends a lot on how well it was installed and maintained, how much it is used and how good the soil and surrounding drainage are.

WHAT SHOULD I DO NOW?
1) Have a Home Inspector you trust do an aboveground septic system screening test (push test) as part of his home inspection. He should, through observation and running a specific reasonable amount of water, determine if the system is functioning at the time of the inspection. He should also try to assess the risk of having a marginal system.

2) You should follow up the Home Inspector's observations by contacting both the septic service company and homeowner to find out if they are aware of any problems with the system.

3) At your discretion, hire a septic system specialist to do an underground inspection of the leaching system. Your decision on whether or not to do this should depend upon the risk of having a marginal system, determined in steps 1 and 2, and your own level of risk aversion. In his inspection, the septic specialist will try to determine if unused portions of the leaching system remain for future use. In general, arranging such an inspection is money well spent for all but relatively new systems.

WHAT SHOULD I DO WHEN I OWN A SEPTIC SYSTEM?
Live normally but within certain prudent guidelines:

1) Have the septic tank pumped out every two years to remove residual solids.

2) Do not flush fat or grease down your drains.

3) Space out water usage to the extent that it is convenient.