This depends on water usage and the amount of waste entering the system. Generally, systems need to be maintained by a septic professional every two to five years.

Make sure the sludge is pumped out of your tank every two or three years. Harsh chemicals like paint solvents, thinners, and nail polish removers should never be poured down the drain. Bleach, sink and toilet cleaners, and drain openers are also harmful to the organisms in your tank that help breakdown bacteria. Diapers, feminine products, cigarette butts, condoms, and cotton swabs can cause blockages and should not be allowed into your system.  

There are several signs of a failing sceptic system. These include: Sluggish or Gurgling Drains & Pipes | Plumbing Backups | Sewage Odour | Mushy Ground or Greener Grass Near Septic System  

The best suggestion is to contact the local local council to obtain a copy of the lot. Some homes may have a white pvc pipe sticking up in the yard, or a concrete square or round lid.

Generally, a septic tank is a minimum of 5 to 15 feet from the home, in a direct line out from your sewage outlet pipe in the basement exiting the building. Tanks vary from 12 inches to 24 inches below the ground in most circumstances. About 95 percent of septic tanks have two cleanout access ports at either end, approximately 6 feet to 7 feet apart. Empty the primary and secondary chambers at each pumping to enable a thorough cleaning and inspection of your system.

It is beneficial to grow grass or ground covers over your septic system to prevent soil erosion. Evergreens such as pines planted absorb excess water, and are beneficial. Avoid water-loving trees such as willows or poplars. Be sure to map where you septic system is for easy access when needed.