Septic tanks receive sewage into a working side, settlement compartment, or solids compartment. The liquids, or effluent, transfer across a baffle to a pump chamber. The baffle is often a simple pipe elbow, “T” assembly, or other arrangement that creates a transfer point below the surface of the sewage in the settlement compartment, thereby holding back heavier solids as well as lighter fats, oil and grease. A siphon assembly or electric pump in the pump chamber will move the effluent (liquids) to a septic field or into a municipal pressure collection system; the solids compartment is cleaned out be a vacuum truck every 1 to 5 years.
Safety Code regulations in Alberta call for installation of septic tanks to follow the Alberta Private Sewage System Standard of Practice (SOP). The SOP indicates that septic tanks must conform to Canadian Standards Association standards. As an industry leader, Tanks-A-Lot follows the most up to date standard: B66-10. The SOP also indicates that septic tanks should be sized according to the ‘expected volume of sewage’. The following table shows the alignment of popular 1-piece septic tank models from Tanks-A-Lot with the guidelines within the SOP. Consideration should also be given to special fixtures such as garburators and ‘fill and drain’ soaker tubs. Larger septic systems can be readily created using 2-tank solutions where one or more tanks are dedicated to settlement roles and one tank is dedicated to the pump chamber role.
Tanks-A-Lot Models 750P and 1020P are available in 1-manhole and 2-manhole versions. All septic tank models are also available with Ultrarib riser starters. Contractor preferences vary, but the 2-manhole versions are more popular because of the simpler ongoing access to the pump chamber, which allows for maintenance and protection of float masts and piping from vacuum truck hoses cleaning out the settlement chamber.
Burial depths for septic tanks are significantly impacted by site factors and mostly range between 2’ to 10’ of earth cover. The Tanks-A-Lot Models 1220P and 1518P have the deepest burial depth rating in the underground concrete tank industry.
All septic tanks from Tanks-A-Lot have the following industry-leading features:
- Canadian Standards Association approved – CSA B66-10
- Raised lip manhole on roof of tank for superior sealing of manhole extensions, Ultrarib riser starter available
- 4” flexible rubber inlet for reduced failures from movement of house sewer line in the tank backfill zone
- Threaded 2” PVC outlet for superior connection of pressure lines to the pump and to the septic field
- Cold seam 1-piece construction locks in the tank roof for superior strength and longevity of the tank
- 20-year limited warranty on materials and workmanship
- Concrete manway cover and 1 roll of butyl rubber sealant for manway extension included at no extra cost
The effluent from most septic tanks is pumped to a septic field, typically consisting of an arrangement of perforated pipe inside a trench covered by a vented chamber. The design of a septic field is significantly dependent upon site factors such as elevations, lot size, lot layout, soil types, and local by-laws. Design of septic systems is usually done by certified installers and professional designers.
For more information about sewage systems in Alberta, or to be referred to a certified installer, please contact us.