Before You Construct an On-site Sewage System
Some Facts a homeowner should know.

The function of a septic tank is to remove and store the solid material and waste matter coming from your residence before the wastewater flows into the drain field. The septic tank should be a watertight chamber constructed of concrete, fiberglass or other decay resistant material that meets provincial specifications. The septic system must be pumped and maintained in order for the system to function properly. The tank should be pumped every two years on average, however if you have a large household or excessive water usage, your tank may need to be pumped more often. The chart below gives a rough idea of the frequency with which you should have your system pumped.

Pumping intervals (years) for 1000 gallon tank.
# Of people	2	3	4	5	6
Years	5.9	3.7	2.6	2.0	1.5

The most important part of the septic system is the drain field. The function of the drain field is to renovate, treat and dispose of wastewater. There are various types of disposal field designs depending on site conditions. A qualified person evaluates the conditions when selecting or designing a system. Most systems now installed are contour (C1, C1 raised, C2, C2 raised, C3, and mound) types.



How Does a Septic Tank Work?
Waste water from the house usually flows by gravity through a building sewer pipe into the septic tank as shown in the image above. The tank is designed to store the wastewater for a day or more before discharging it to the disposal field or to further treatment. During this time, the heavier sewage solids settle to the bottom to form a sludge layer. Lighter solids, fats, greases, and oils float to the top to form a scum layer on top of the water. This leaves a middle layer of partially clarified liquid wastewater. The septic tank holds sewage long enough for solids to settle or float, and for bacteria to break down some of the solids naturally. The function of the baffle is to prevent the layer of scum from entering the drain field. The wastewater travels from the tank to the field by one of two methods; gravity or pressure. Gravity distribution systems flow the wastewater from the tank and is distributed throughout a perforated pipe. Pressure distribution is installed similar to the gravity method. The only difference is the addition of a pump tank. This pump tank is placed between the septic tank and the drain field which sends the wastewater into the drain field in cycles. This provides improved distribution of the wastewater throughout the drain field. Once in the drain field, the wastewater is distributed throughout layers of gravel and into the soil where it is filtered and purified.



Design, selection, construction, and ownership of an onsite sewage disposal system are governed by the Environmental Act and the On-Site Sewage Disposal Regulations. Once the system is completed, the homeowner is responsible for care and maintenance. Proper use and regular maintenance are the keys to long term satisfactory performance of an on-site system. Most failures are due to poor maintenance, or improper use of the system by the owner - what goes in it, and what goes over it!

Please check out the Do's and Don't's section for more information on how to care for your septic system.

How to extend the life of your system?
It is very important to understand how your septic system works so you can help prevent malfunctions and failures from occurring. Through proper maintenance and regular pumping you can extend the life of your system. We also recommend the addition of a septic filter for added protection against clogging. Clogged drain fields are the leading cause of septic system malfunctions and failures. Replacing a system can be a costly investment. As the natural circulation beneath the ground becomes compact, improper circulation and drainage will lead to failure within the system. A filter will help your system to run more effectively and can prevent most clogging problems from occurring.

View Filter on our "Products and Services" page.

Exerpt from the Nova Scotia Environment and Labour - In cooperation with Waste Water Nova Scotia Society.

To download this full document with all the information please go to this link: http://www.gov.ns.ca/enla/pubs/bycaosss.pdf