The planning phase of a new home construction project can be quite exciting. A septic system must also be constructed if there is no adequate sewer connection at the location.
Selecting the appropriate septic system for your needs is crucial, and there are many factors to take into account while designing.
The rules pertaining to septic systems should be addressed first. Other factors to think about are:
- The property’s topography and landscaping.
- Where and how big a septic tank is required.
- Size of treatment field area.
Whether planning a septic system for new construction or an addition, Soilworx has put up a list of essential components to take into account.
Keep reading for more information.
Consider The Terrain And Landscaping During The Design Process
Septic systems work best in level terrain. It can be problematic to install a septic tank or treatment field area at the base of a hill or other sloping terrain.
A heavy downpour that cascades down the slope may saturate the treatment field area or tank with water.
The soil type must be considered while designing a septic system. To treat the water exiting the septic tank, the soil in the treatment field area must be tested so that we know the maximum hydraulic rate we can load the soil with to avoid having a failure or over-stressing the soils.
High clay or gravel content soils may not treat the wastewater adequately. In high-water-table areas, a particular type of treatment field area is necessary to prevent untreated wastewater from entering the groundwater before full treatment has occurred in the soils.
It’s also crucial to landscape the treatment field area and the area around septic tank. The best option is to plant drought-tolerant grass or ground cover.
Large-rooting plants and trees have the potential to harm the treatment field area pipes. For the same reason, nothing substantial (such as swing sets or sandboxes) should be positioned over the treatment field area.
Vegetable gardens should not be located overtop or near a treatment field area. Vehicular traffic should be avoided overtop a treatment field area. Also, structures, buildings, driveways etc cannot be placed overtop a treatment field area.
Septic Tank Size And Placement
It is crucial that your septic tank be the right size. Alberta regulations require the septic tank to have a minimum 24hr hydraulic retention time, which is calculated from the expected flows from the house and the accumulation of the sludge and scum. Proper sizing ensures adequate settling of the solids within the tank before the effluent is sent to the field area for treatment.
The number of bedrooms is the main criteria used to determine the septic tank size. Other fixtures like tubs, laundry, showers, etc must also be taken into consideration when sizing a septic tank and treatment field area.
Determining the necessary tank size is not the only crucial step in the septic system design; choosing the location of the tank is as crucial.
It is best to install the septic tank in a convenient location. Every three to five years, the tank needs to be pumped out (cleaned) in order to properly maintain the septic system.
It is not recommended to install decks or sheds over the treatment field area or septic tank. Damage to the system and early failure might result from driving over the treatment field area or septic tank, or from heavy objects.
Septic System Design And Treatment Field Areas
The septic system consists of more than just the septic tank. The tank and the treatment field area are equally significant. There are various kinds of treatment field areas allowed to be installed in Alberta.
A traditional treatment field area is entirely subterranean. It’s a big, rectangular space with individual trenches with pipes and gravel or chambers.
Via the pipelines, the septic tank’s effluent is appropriately dosed to the soils where final treatment happens. It requires the right soil conditions for this system.
The soil shouldn’t be overly compacted, hard, or situated too near to groundwater. All treatment areas must be installed in virgin soil; they cannot be installed in excavated areas, or where there is fill or where the soil has been compacted by heavy machinery.
A mound system can be utilized if the soil in the treatment area has higher clay content or poorer structure, or if there are highly permeable layers such as gravel seams close to the surface. A mound system must be pressurized with a pump and is built directly on top of the existing ground. The septic tank’s effluent is pumped to the mound so that it can be treated there before it enters the soil beneath.
There are other options as well, such as an LFH At-grade which is built within the trees / forested areas. A private sewage system designer can help you know all of your available options.
Distribution Box
A distribution box can be used in traditional treatment field areas to help distribute the effluent equally to all of the trenches (via gravity distribution).
How A Septic System Works
The 1st chamber of the septic tank receives all of the household wastewater that is flushed or goes down the sink.
Some people think that there is a lot of bacterial action in the septic tank but the truth is that there is very little bacterial action. The main mechanism of treatment in a septic tank is settling and separation. The majority of the bacterial action happens in the soils, not in the septic tank.
Thick solids have a tendency to sink. The solids decompose over 24 to 48 hours to produce a layer of sludge at the bottom of the 1st chamber of the septic tank.
Grease, oils, and fats are lighter floatable materials that accumulate to form a scum layer on top of the liquid in the tank, along with toilet paper.
The effluent that has been “clarified” through settling in the 1st chamber then passes to the 2nd chamber.
The effluent from the 2nd chamber is then sent to the soil in the treatment area, where bacteria, microbes and other organisms treat and clean the wastewater before it goes back into the environment.
In a properly sized and designed system, 95% – 99% of the contaminants in the sewage are removed or reduced to levels that are safe before it reaches groundwater.
The Right Septic System Design Is Important
Verify that the septic system is appropriately sized for the land. Families and the environment are kept safe by adhering to local requirements and doing installations correctly.
Septic systems are designed and serviced pumped by Soilworx.
For expert advice and assistance with your septic system needs, contact Soilworx today!
