With proper construction and operation, a septic tank system will need very little maintenance. It should not be necessary to pump out the tank more than once every three years. It should, however, be inspected by a sewage hauler or onsite sewage system professional every three to five years and be pumped when required.
Failure to pump out a septic tank when required may result in sludge or scum being carried out into the tile field which in turn will clog and cease to function. In this event not only will the tank have to be pumped out but the tile bed may have to be replaced. Septic tanks are now equipped with a filter on the outlet side of the septic tank. When checking your tank or it is pumped, ensure the filter is cleaned.
The Ontario Building Code 18.104.22.168(1) states that “Septic tanks and other treatment units shall be cleaned whenever sludge and scum occupy 1/3 of the working capacity of the tank.”