During COVID, many city dwellers have become more open to considering a rural property as they move out of the Greater Toronto area. More space, more freedom. And… a septic tank? This unfamiliar set up that likely also contains a well for water can throw people for a loop.

But, it shouldn’t.

With a few extra steps involved, a septic system is a great setup for rural homeowners or those with an Ontario cottage. Basically, anywhere that doesn’t have municipal plumbing and sewage.

In this blog, we’ll explain the specifics around a septic tank and where you’re likely to find one. We’ll also discuss how to maintain a septic system as well as costs associated with a septic tank.

What is a septic tank?

A septic tank (a component of a larger septic system) is an underground chamber made of concrete, fiberglass, or plastic through which domestic water flows.  In easier to understand terms: it’s a giant underground container that is located in your yard.

Since almost all rural properties with septic tanks are detached homes, it’s likely only used by one family.

Waste water from your house goes to it and is treated by chemicals in the septic tank. This tank is typically located somewhere underground on your property.

Usually it’s easier to spot as grass grows a little darker or appears healthier in the general area (drainfield)

The septic system usually consists of two main components: the septic tank and the absorption bed that is sometimes referred to as the disposal, leach or drain field. The septic system is connected to the house by sewage piping.

Why would I choose septic?

It’s a good question, but it’s not really about choice. Many people believe that a septic system is an old school, outdated system. But it’s not.  A septic tank and system are required in areas where municipal infrastructure doesn’t exist.

This is why the majority of septic tanks are found on rural properties.  In fact, some people prefer the use of a septic tank as it allows for local water tables to be naturally replenished.

How does a septic tank work?

The wastewater from your home—from toilets, sinks, showers, and appliances—exits the house through the pipes into the septic tank. Once in the tank, the solid matter (also known as sludge) settles to the bottom.  Here’s a step by step chronological explanation of the process:

When you use the water in your house (dishwasher, sink, toilets, laundry), all the water exits the home from one main drainage pipe into the septic tank. The tank is likely located on the side or back of your home.

If you have a well, it’s likely you’ll find your septic tank on the opposite side of the house. This is by design- you don’t want sewage leaking into well water.

The septic tank holds the wastewater long enough to allow solids to settle down to the bottom forming sludge, while the oil and grease floats (effluent) to the top as scum. The middle layer is watery waste water (effluent)

The effluent then exits the tank into the drainfield which is a shallow, covered, excavation made in unsaturated soil. A filter prevents most solids from entering the outlet pipe. The drain septic field provides a large area where bacteria can thrive and treated water can seep into the ground (This is where you’ll likely see greener grass at the surface!)

Holes in the drain septic field pipe allow effluent to seep into surrounding gravel.


If you overload the drainfield with too much liquid, it can flood, causing sewage to flow to the ground surface or create backups in toilets and sinks.

Gravel around pipes allows water to flow into soil and oxygen to reach bacteria and clean water to seep down into the groundwater and aquifer.

septic tank clean out
septic tank clean out

How often should I have my tank cleaned out?

Ideally, you’d have your septic tank cleaned out every two years in Ontario. However, this is assuming the system is receives regular use. If you have a rural property that only has seasonal use (like a cottage), you don’t want to clean it out too often and keep it empty.

At the same time that you clean out the septic, you should also inspect it to ensure that all the components are working properly. You should also monitor for any leaks and corrosion. A septic inspection is not typically done by the same inspector that would perform a home inspection. Read: Guelph home inspectors

In most real estate offers, the buyer will require the seller to clean out the septic system prior to closing at their expense. This ensures that the system is empty and inspected for the new buyer by a professional. The cost for this ranges between $300-$500 depending on the outcome of the inspection.

How long does a system last?

Most people think that a septic system would have the life of a modern day furnace or AC or roof. But it doesn’t. In fact, we had clients recently purchase a house that was built in 1970 and the original septic was still going strong after 51 years! This is an anomaly however.

The general concensus is that most septic systems last 20-30 years. But there are a variety of factors that impact the life of a septic system.  Here are a few:

Who’s using it?  the general assumption is that you will use at least 110 gallons of water per bedroom per day. More people in the house means it’s working harder. Less people in the house may mean it’s not working hard enough.

Chemicals – some household products have chemical pollutants that can be toxic to the beneficial bacteria in the septic system. The more a septic system owner uses these harmful products, the shorter the lifespan.

Soil quality – the quality of soil will determine how durable your septic tank is. For instance, acidic groundwater can corrode a concrete septic tank.

How do I know I need to replace my septic system?

How old is it?

If your septic system is 20+ years old and you are pumping it more frequently to keep it functioning properly, this may be sign of things to come. Components may be starting to fail.

It’s original use is now obsolete:

As mentioned, the size of the septic is loosely based on the number of bed rooms and square footage of a house. Have you done a renovation to add more bathrooms? Is the house much bigger than it was when you originally decided to install a septic system?

If your tank is too small, it might be time to upgrade the system to serve your family and your lifestyle better.
 

Slow Drains:

If it takes a long time for your sinks or bathtub to drain, it’s a sign you have a septic problem. If it’s just one or two drains, it could be a minor clog. But if all your sinks are draining slowly it might mean you have a more significant problem.

It might mean the water is moving slowly through the septic tank because of sludge buildup at the bottom.  Get a professional out to inspect and possibly clean out the system to get a better idea.

Standing Water in the Yard:

You don’t want to find standing water in your yard from your septic system. It could mean a number of issues from minor repair to major replacement. Don’t ignore standing water because the problem won’t go away, it’ll only get worse. Get a professional out ASAP.

It might not be your septic tank causing you problems. Sometimes, standing water is from a failing drain field.
Fixing a drain field issue begins with using a chemical or biological additive to clear the blockage. Sometimes, you can replace the drain field without needing to replace the septic tank. 

Contaminated water:

If you discover pollution in water sources either from colour or odour, then it’s essential you investigate the issue immediately.


Other Septic Systems Issues

Replacing the septic tank is a 2-3 times per century occurance. A lot of these signs can be symptoms of smaller issues in need of minor repairs. You might need your septic tank pumped or the system flushed to remove clogs.

It’s also possible that your home had a septic system when originally built. However, with infrastructure improvements the home would eventually connect to municipal sources. This would make your septic system non-functional, but still buried.

If you’re selling a home and are aware of a non functioning septic system in the yard, you need to disclose this to potential buyers.  It may be less of a concern in a strong sellers market, but ensure that you’re working with the best Guelph real estate agents who knows the ins and outs of the area.

This also applies to wells that are no longer in service (de-commission). These were an older water source, but homes now connect to municipal sources.

How much does it cost to replace a septic system?

The price that you should expect to pay for the system and installation will vary widely depending on the size of the home, soil conditions and the type of system you require or decide to go with.

Replacing a septic system is similar to buying a car: you need to consider how you will use it. Most basic residential systems will range in price between $10,000 and $25,000.

Typical replacement costs are higher depending on how much soil damage there is. As well, the specific site conditions that you need to restores after construction.

Did you renovate or modify your home since the current septic system was installed? Consider the current (and future) use of your home when deciding on a septic system. The current style may no longer be relevant to your needs.

Will a traditional home inspector check the condition of the septic system?

No. If you’re buying a house that has an inspection of the septic tank as a condition, a general home inspector will not do this. You’ll need to find a septic system inspector that is certified to check your tanks, baffles, and piping. They’ll also evaluate the inside of septic tanks using a camera to check on concrete conditions; and make sure wastewater is going into the tank, not leaking to the surface.

If you’re considering a rural home, get in touch with Beth and Ryan, Guelph Real Estate agents. They can help you!

Related: 16 things to consider when buying an older home.