Frequently Asked Questions about Septic Systems

What’s a septic tank?

A septic tank is one of the largest cost investments in home ownership. The typical septic tank is a rectangular or cylindrical container made of concrete, fibreglass, or polyethylene. The tank is buried in the ground. Wastewater from your toilet bath, kitchen, and laundry flows into this tank. The solids settle to the bottom, while the lighter solids like grease and fats float on the top. This is called a scum layer. In the middle of these two layers is the liquid layer, which is composed of grey water and other liquids that get flushed into the tank.


Septic tanks may have one or two compartments. Two compartment tanks work better at settling out the solids. In addition, two compartments are required for new systems. Tees and baffles are provided at the tank’s inlet and outlet pipes. The outlet pipes keep the scum or solids in the tank. All tanks should have accessible covers for checking the condition of the baffles and for pumping both compartments. Some tanks may have risers on them that extend from the tank to above ground and must be secured to prevent accidental entry into the tank.


Solids that do not decompose remain in the tank and, if not periodically pumped out, will overflow into and eventually clog the field, causing it to age prematurely. This will cause the homeowner to replace the septic field.


Why own a septic tank?

Approximately 25% of Canadians have septic tanks. They are used to take care of wastewater in a rural or lesser populated area. A septic tank treats the wastewater on-site. The treated liquid (effluent) is then incorporated back into the ground water, contaminant-free.


How do septic systems work?

A septic tank contains bacteria that breaks down organic matter and separates floating and sinking waste. Treated liquid (effluent) is then channelled into the leach field (the soil filter). Other systems use gravity or pumps to filter the liquid.


Why do septic systems fail?

Most failures are due to improper tank maintenance or poor tank design. The tank may have been installed in an area with less than ideal soil or other factors. The system can also become clogged if it is not pumped regularly (every 2-3 years).


How do you know when a septic system is failing?

There are many symptoms of a failing septic system. The ground around the tank or over the leach field may be soggy, you may experience sewage back up or slow draining, or you may notice a sewage smell, especially after it rains.


What happens when my septic system fails?

If you don’t have your system pumped regularly, the solids that sink to the bottom of the tank get too compacted, which makes them hard to vacuum up. If the tank gets too full, solids will back up and get into your field lines, causing the lines to be plugged. Flushing the lines and adding a bioremediation product can get the lines cleared, but if the septic field has been impacted too many times, the field may have to be replaced. If the system backs up into the house, the problem can be very expensive as well. Whatever has been saturated with septage (septic waste) has to be removed and the area disinfected. Unfortunately, this often means a complete gut of the affected areas to remove the septage contaminated building materials. By far, the least expensive option is to get your tank emptied by a professional waste disposal company.


How long can a septic system last?

Some systems can last up to 20-25 years. There have been some systems that last even longer. The septic system will only last this long if you have regular maintenance and keep the system cleaned out.


What can’t I put down the drain?

Do not flush or put down the drain: coffee grounds, floss, diapers, kitty litter, tampons, cigarette butts, grease, paper towels, paints & painting-related solutions, and other toxic chemicals. Learn more about septic dos and don’ts.


Can I install my own septic system?

Anyone who works on any part of a septic system is required to be licensed by the Province of New Brunswick and contractors performing installations or repairs to septic systems are required to adhere to the Regulations and Guidelines as set forth by the Department of Health.


How do I maintain my septic system?

The most important step is to have your system routinely cleaned. We recommend the system is cleaned every 3 years, depending upon how many people live in your house.


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