Septic Systems

How to Have Your Septic System Inspected.

When Buying a Rural Property usually the seller will have the septic system pumped out  prior to the closing date.   The Angus Home Inspector recommends that you have the system pumped out by a licensed installer, who can then provide you with a written assessment of the system.

Septic systems are used when sewage treatment plants are not accessible. They safely treat and dispose of wastewaters produced in the bathroom, kitchen, and laundry. These wastewaters may contain disease-causing germs and pollutants that must be treated to protect human health and the environment. Although septic systems are usually a permanent solution to wastewater treatment and disposal, they sometimes serve as a temporary solution until sewer lines are installed.

Did you know that as a homeowner you’re responsible for maintaining your septic system? Did you know that maintaining your septic system protects your investment in your home? Did you know that you should periodically inspect your system and pump out your septic tank?  Some municipalities are now performing annual inspections of septic tanks and at the expense of the home owner.

A septic tank is simply a big concrete or steel tank that is buried in the yard. The tank might hold 1,000 gallons (4,000 liters) of water. Wastewater flows into the tank at one end and leaves the tank at the other. The tank looks something like this in cross-section:

In this picture, you can see three layers. Anything that floats rises to the top and forms a layer known as the scum layer. Anything heavier than water sinks to form the sludge layer. In the middle is a fairly clear water layer. This body of water contains bacteria and chemicals like nitrogen and phosphorous that act as fertilizers, but it is largely free of solids.

Wastewater comes into the septic tank from the sewer pipes in the house, as shown here:

House Septic System

 

A is the Toilet
B is the Sink
C is the Bathtub
D is the Vent Pipe
E is the waste pipe going to tank

A septic tank naturally produces gases (caused by bacteria breaking down the organic material in the wastewater), and these gases don’t smell good. Sinks therefore have loops of pipe called P-traps that hold water in the lower loop and block the gases from flowing back into the house. The gases flow up a vent pipe instead — if you look at the roof of any house, you will see one or more vent pipes poking through.

As new water enters the tank, it displaces the water that’s already there. This water flows out of the septic tank and into a drain field. A drain field is made of perforated pipes buried in trenches filled with gravel. The following diagram shows an overhead view of a house, septic tank, distribution box and drain field:septic system drain field

 

A typical drain field pipe is 4 inches (10 centimeters) in diameter and is buried in a trench that is 4 to 6 feet (about 1.5 m) deep and 2 feet (0.6 m) wide. The gravel fills the bottom 2 to 3 feet of the trench and dirt covers the gravel, like this:

The water is slowly absorbed and filtered by the ground in the drain field where bacteria continues to work on the liquid. The size of the drain field is determined by how well the ground absorbs water. In places where the ground is hard clay that absorbs water very slowly, the drain field has to be much bigger.

A septic system is normally powered by nothing but gravity. Water flows down from the house to the tank, and down from the tank to the drain field. It is a completely passive system.

You may have heard the expression, “The grass is always greener over the septic tank.” Actually, it’s the drain field, and the grass really is greener — it takes advantage of the moisture and nutrients in the drain field.

Homeowners moving from cities will find a big difference in what products they can put into their septic system.  Anything that floats will pass through the septic tank and find its way into the drain field,  this behaviour can eventually clog the drain field lines causing backups and an expensive repair.

Ten simple steps you can take to keep your septic system working properly.

  1. Locate your septic tank and drainfield. Keep a drawing of these locations in your records.
  2. Have your septic system inspected at least every three years.
  3. Pump your septic tank as needed (generally every three to five years).
  4. Don’t dispose of household hazardous wastes in sinks or toilets.
  5. Keep other household items, such as dental floss, feminine hygiene products, condoms, diapers, and cat litter out of your system.
  6. Use water efficiently.
  7. Plant only grass over and near your septic system. Roots from nearby trees or shrubs might clog and damage the system. Also, do not apply manure or fertilizers over the drainfield.
  8. Keep vehicles and livestock off your septic system. The weight can damage the pipes and tank, and your system may not drain properly under compacted soil.
  9. Keep gutters and basement sump pumps from draining into or near your septic system.
  10. Check with your local health department before using additives. Commercial septic tank additives do not eliminate the need for periodic pumping and can be harmful to your system.