Septic Systems: The Inside Story
Class 4 septic systems are divided into two components, the septic tank and the septic field or leaching bed. Waste is piped out of the house into the septic tank, which is essentially a water clarification tank, in which anaerobic bacteria break the waste down into solids (sludge), liquid effluent, and scum.
The solids settle to the bottom, the scum floats to the top and the liquid effluent flows through an outlet pipe into a distribution chamber, where it is directed to the septic field. The septic field is an effluent water disposal system, where the liquid is channeled through perforated pipes to different parts of a field of loose gravel.
Septic tank materials that initially float in the scum layer are kept out of the drainage system by an outflow tee or baffle. If the tank is not pumped regularly, the level of solids can rise, and if it approaches the level of the outflow tee, scum and solids can proceed out into the drainage system, clogging the pipes and gravel – and eventually preventing the absorption of the water by the surrounding earth.
A Class 5 septic system is a holding tank for the storage of sewage at the site where it is produced. A typical holding tank system is comprised of a single compartment tank with a pump-out stack and an audible or visual warning device to alert the homeowner when the tank requires emptying. A holding tank is costly to operate, places restrictions of the owner, and is dependent on Class 7 (hauled) sewage system for waste collection and disposal.
A property served by a holding tank system requires an agreement registered on title to notify current and future owners of the servicing restrictions on the property.
Care and Maintenance
With proper care and maintenance, your septic tank and field should provide many years of trouble-free service. There are, however, some important steps to follow to help you maintain the proper operation of your sewage disposal system.
The septic tank in a residential system should be inspected regularly for sludge buildup. The tank should be pumped by a licensed septic tank pumping contractor when necessary. Under normal use a septic tank should have its contents removed every three to five years.
The use of starters, bacterial feeds or cleaners in a septic system is normally not necessary.
The final grade (top soil) over the field should not be altered after it has been installed and inspected, and should be kept grassed after installation. Shrubs, trees or gardens should not be established over the septic field.
Discharge from evestough drains and sump pumps should not be directed into or over a septic field, and lawn sprinkler systems must not be located within this area.
Limiting excessive amounts of water in a short time can help reduce disruption of the septic process. You may want to consider the following water use reduction practices:
Install water saving shower heads, sink aerators, and low-flush toilets.
Use dishwashers and washing machines only for full loads, and stagger the loads through the week.
Don’t run water continuously when shaving, brushing teeth, rinsing dishes or veggies.
A container of water in the fridge prevents the need to run water continuously for a cold drink.
The installation of garbage grinders, large volume hot tubs or spas are not recommended unless the septic system has been sized to accommodate their use.
The use of biodegradable products is highly recommended. Disposal of non-bio-degradeable products such as condoms, feminine hygiene products, plastics, dental floss, etc. is strongly discouraged.
If you have questions regarding the care and maintenance of your septic system, consult your contractor or the Environmental Protection Division of your local Health Department.
The standards for private sewage systems are prescribed in Ontario Regulation 358/90, under the Enviromental Protection Act, and the Guidelines established by Ministry of Environment, and requirements of your local munipality or township.
General Guidelines for Purchasers
If the system is 5-7 years old and has never been pumped it is unlikely that there are serious problems.
If there is no record of the system having been pumped but the owner has a vague recollection of pumping the system at some time in the distant past, figure that it has never been pumped.
If the system is over 10 years old and has never been pumped, it is possible that there has been some damage to the septic field, and if it’s not been pumped for over 15 years it is quite likely.
Flushing dye through the system looks good but will only indicate systems that are already seriously clogged, in which case there should already be more obvious signs.
Flushing dye may not indicate serious defects or indicate systems that are close to failure but still functional.
If you are on a septic system, adding a bedroom, even without adding a bathroom, may mean having to increase the size of the tank and drainage field.
The only way to make an accurate determination of the system is to have a licensed septic contractor perform a tank, distribution chamber and field inspection.