Humans use a lot of water: besides what we eat and drink, an average adult in North America uses about 300 litres a day. This large amount, along with waste, must be effectively managed to prevent contamination and promote sanitation.

So where does it all go? For most people, the waste disappears down their toilet, never to be seen again, along with the water from sinks, showers, or any drains in their home. These are attached to city sewer pipes which carry the sewage to a local treatment plant. The raw sewage is treated, removing harmful bacteria and pathogens, and released into rivers or the ocean.

But some people live in areas where city sewer systems are not available. What happens, then?

In the old days, they would go to the outhouse, which was basically a toilet seat strategically placed over a deep hole. This method worked in areas with lower populations, but with more people came more excreta, which caused problems.

As populations increased, raw sewage would seep into rivers and groundwater, which caused sanitary issues with drinking water. In Europe, as early as the 1500’s laws were passed forcing homeowners to install cesspools to control waste from simply being dumped in the streets. These cesspools would be emptied by muckrakers and hauled to farmers’ fields to be used as fertilizer.

Septic systems are designed by engineers and septic professionals called ROWPs. What is a ROWP? A Registered Onsite Wastewater Professional. 

A ROWP will assess the type/amount of wastewater coming from a home (depending on how many plumbing fixtures and occupants) and will conduct tests on the native soil and environment that the septic system will be installed.

The septic system and leach field need to be large enough to safely neutralize the pathogens in the effluent before they enter the groundwater.

Sometimes the native soil is not conducive to supporting a leach field. Either it will drain away effluent too quickly, or it will not drain it adequately. In those instances, a ROWP will design a system to include different equipment to slow or speed up the dispersal. This might include increasing the size of the leach field for slow-draining soil or perhaps bringing in offsite sand, gravel, or other materials to control the effluent.

What I’ve described so far is a Gravity Septic System. Gravity septic systems function without any pumps, and they do not require any electricity to operate. As new sewage enters the tank, it displaces effluent, which flows out of the tank into the leach field.

Modern septic fields are all made from concrete/plastic tanks and plastic perforated pipe covered in filter fabric, which can last for many, many years. Prior to that, old septic systems were made from short pieces of clay pipe. Over time these would get compromised by tree roots, collapse, or get filled with native dirt and sediment. This, in turn, would cause the effluent to stop flowing, and it would back up into the tank.

In some instances, the water table is too high to install a gravity system. In this scenario, a leach field is built elevated above the ground in a sand mound. Since it is above ground, we can no longer depend on gravity to disperse the effluent, so we switch over to a forced-flow effluent system. Usually, a secondary tank is installed between the septic tank called a pump chamber. The effluent falls into this tank, and the pump pumps the effluent into the elevated sand mound.

These systems DO require electricity, and the pump will not operate when the power is out. The good news is that it typically will take many hours before the pump chamber is too full, and as soon as the power turns back on, the pump will be triggered to lower the effluent level in the tank.

In a leach field, ROWPs will sometimes specify different pieces of equipment to aid in the dispersal of the effluent, depending on the leach field media. For instance, if native soil drains too quickly, they might recommend absorbent modules or mats that hold onto the effluent longer so that it doesn’t disperse too quickly.

If a ROWP would like to have the effluent dispersed more quickly, they may employ large chambers in the leach field, resembling large arched half pipes that create more surface area for the effluent to leach into than a buried pipe could provide.

Do modern septic systems fail? Yes, they do. But if a proper maintenance schedule is followed, they will last for many decades before needing to be replaced. What should you do?

Make sure that you get your septic tank pumped out every 2 to 5 years. If the system is brand new, make sure this is done before 1 year of operation to ensure the system is operating properly, and you can still involve the system installer in case there are issues.

A proper septic service provider will be able to pump out your trash tank and test the function of your system to ensure it is healthy.

Make sure to check the function of your system constantly:

• Are sinks and toilets draining too slowly?
• Are there gurgling sounds in the drainage plumbing?
• Do you smell unpleasant odours around the septic field?
• Is there soggy or wet ground around the septic field?
• Is sewage appearing on the surface?
• Are toilets burping or bubbling excessively?

If so, call a professional right away to take care of the problem before you have a serious sewage problem in your house!

Proper usage and care play a significant role in maintaining a healthy septic system. 

• Do not flush non-compostable materials! Tampons, condoms, pads, wet wipes, kids’ toys, etc. These do not decompose and will need to be pumped out of your tank at some point, and could also get stuck in your pump. 
• Do not use harsh chemicals such as anti-clogging agents (Drain-O).
• Do not install a garburator without contacting a ROWP first, often times septic fields are not large enough to accommodate this added waste.

Only if they haven’t been installed properly according to local codes or a local ROWP’s instructions. In some regions, frost goes very deep into the ground, and each climate region will have different requirements for the depth of tanks and leach fields. If installed properly according to these standards, a septic field will work perfectly fine through the coldest weather.

It depends on your insurer! Typically an insurance company will ask for details on your septic system. These can either be found on your home inspection report, or if it is a new home, the ROWP will have provided you with a complete binder with all the information on your system that you can forward to your insurance provider. 

Typically if the system was installed as per the local standards, it is an insurable part of your home, but it’s up to you to find out with your insurer!

If a system has been installed incorrectly or isn’t maintained properly, it can be very, very bad. However, if installed according to a proper ROWP design, it is very, very good – keeping your family safe and the groundwater safe.