A vital part of buying a new home is inspecting the septic system.
You may have questions about its integrity and functionality if it’s sat unused for years.
Septic system repairs are expensive.
You may not have the budget for it after buying the home.
Here’s what you need to know about how long a septic system can sit unused.
How Long Can A Septic System Sit Unused? (What To Know)
Septic systems can last 15–40 years when maintained.
A septic system that’s sat unused may last even longer.
There are a few factors that can influence how long a septic system can last unused.
We’ll go over four of those factors to help you determine how long a septic system can last unused.
1. Septic Tank Materials
Septic tanks come in a few different materials.
One of them is steel.
The problem with steel is that it can corrode over time.
Even if the septic system sits unused for several years, the steel is still subject to groundwater exposure.
That exposure can cause it to rust and deteriorate.
However, it may last longer than a septic tank that is in use.
When a septic system is in use, then the parts are always wearing out over time.
Every use wears the parts down a little more.
An unused septic tank doesn’t have this problem.
As such, your unused septic system made of steel may last longer than a used septic system made of steel.
The other type of material is a combination of concrete and fiberglass.
This is the strongest material.
It avoids problems with corrosion.
While the tank itself can last a long time, you’ll still have problems with the parts.
An unused septic system made of concrete can last for several decades.
A used septic system made of concrete can last up to 40 years with proper care.
It’s the parts that will wear down before the concrete tank.
2. Vehicle Traffic In The Piping Area
Another factor that influences the lifespan of an unused septic tank is vehicle traffic.
Your septic system uses pipes beneath the ground to deliver liquid waste into the soil.
These pipes are delicate.
While walking over the ground doesn’t cause a problem, using vehicles and heavy machinery does.
If anyone ever drove their car or equipment over the pipes, then there’s a chance that the pipes have broken.
An unused septic tank has a higher chance of surviving longer than a used septic tank because it means no one is on the property.
As a result, no one will drive their car or equipment over the pipes.
You need to empty a used septic tank.
That requires the use of a truck and pipes.
Most contractors know to stay away from the pipes.
If the area is difficult to reach, however, then they may have no choice but to drive closer to the pipes to empty the tank.
The pipes may break, and the used septic tank may need repair.
A used septic tank also means that people are living at the home.
They may need equipment on-site for various projects.
Any of those vehicles could break the pipes.
An unused septic system lasts longer because there are fewer threats to its piping.
3. Root Clogs And Damage
Another threat to the lifespan of a septic system is tree roots.
As trees grow, their root systems expand.
There could be roots in your backyard that have grown to several meters in length.
One of those roots can pierce through a pipe.
It can clog the pipe or break it entirely.
The problem with an unused septic system is that no one is there to keep an eye on the trees and root systems.
In this case, a septic system that’s sitting unused may only last a few years.
It depends on the proximity of the closest root system.
A used septic system will last a few more years if the homeowners stop the problem before it occurs.
4. Flooding Groundwater
One final factor that can influence a septic system’s lifespan is the groundwater.
A septic system rests deep within the ground.
The presence of groundwater is minimal at best.
However, if the home is in an area where groundwater floods, then it could damage the septic system.
When groundwater floods the cavity of the tank, it causes the tank to rise.
When the tank rises, it forces the pipes to break off.
The septic system breaks.
An unused septic system won’t last long if it’s in an area where groundwater floods.
No one is there to drain the groundwater or protect the tank.
A septic system that’s used will have someone to care for it.
They’ll be able to correct the flooding problem before it can damage their septic system.
How Long Do Steel Septic Tanks Last?
Steel septic tanks last 15–20 years if they’re used.
They may last 10–30 years if they’re unused.
The biggest threat to steel septic tanks is corrosion.
Any contact with water has a chance to make the tank start to rust.
One of the most common ways that a steel septic system breaks is its bottom rusts out.
The solid sludge weighs down on the bottom and breaks it open.
Corrosion weakens its bottom which allows the solid waste to break the tank further.
The baffles can also rust and break.
Even the top of the tank can rust and become a danger.
An unused steel septic system may last longer because it isn’t pumped full of wastewater.
The parts aren’t moving either.
As long as it doesn’t have contact with water, a steel septic system could last for several decades.
How Long Does A Concrete Septic System Last?
A concrete septic system can last 10–40 years if it’s used.
An unused concrete septic system can last virtually forever.
Concrete septic systems don’t have the same problems with water as steel systems do.
The only thing that can break a concrete septic system is pressure on the pipes, root systems, and worn parts.
Because of that, a concrete septic system that’s sat unused could last forever.
What Happens to A Septic System If It’s Unused?
Nothing happens to a septic system if it’s unused.
A septic system that sits unused is safe.
It isn’t subjected to wear and tear through use.
If the tank had prior use, then it may contain solid waste inside of it.
At most, a septic system that’s sat unused is only breaking down that solid waste.
Depending on when someone uses the system again, even that solid waste may be gone.
Do Septic Systems Go Bad If They’re Unused?
No, it is not bad if septic systems sit there unused.
That doesn’t mean that it’s in the best shape of its life, however.
As the new owner, you should always inspect the septic system before using it.
You can’t be sure what the previous owner did to it.
However, any problems that stem from the septic system are unlikely due to it being unused.
If anything, going unused is what likely prolonged its life.
Signs Your Septic Tank Is Failing
There are a few signs that can indicate your septic system is about to fail.
1. Sewage Backups
Nothing is more distressing than having sewage back up into your home.
Whether it’s coming through the toilet, shower, or sink, it’s a horrible mess.
It’s also a sign that your septic system is failing.
Something is keeping the wastewater from expelling through the pipes and into your soil.
A clog could be to blame.
Your tank may need emptying.
The problem could also rest with the septic system’s pipes.
No matter the cause, if you see sewage backups in your home, then it’s time to call a professional.
2. Slow Drains
When you use the sink, shower, or toilet, you expect the contents to run down the drain immediately.
Functioning and healthy plumbing will guarantee that this will happen.
If the water and its contents are slow to drain, then the issue could rest with your septic system.
Slow drains indicate that there’s a clog somewhere in the tank.
It could be from the house’s interior plumbing.
It could be the tank if it’s full.
The problem may also stem from the pipes leaking the wastewater into the soil.
Slow drains are often the first sign that your septic system needs help.
3. Gurgling Sounds
Your plumbing is usually quiet.
You only hear the rush of water as it passes through the pipes.
If you start to hear a gurgling sound, then something isn’t right.
The sound of gurgling means that there’s air in the plumbing.
Something isn’t draining right.
Gurgling sometimes goes hand-in-hand with sewage backups.
If you hear gurgling, then it’s time for someone to inspect your septic system.
4. Standing Water In Drain Field Or Tank Area
Standing water in your yard is never a good thing.
If the water is in the drain field or tank area of your septic system, then it’s a sign that your septic system needs repair.
Septic systems work by pushing wastewater into the soil of an area that’s designated as the drain field.
The soil filters the water.
Bacteria, viruses, and other harmful pollutants become trapped in the soil.
The water, which is mostly clean by that point, becomes part of your groundwater.
Over time, the good bacteria that exist in your soil start to die.
They can no longer break down wastewater.
Other elements in the soil can also make it impossible to absorb the water.
As a result, you have standing water in the drain field.
This water is a biohazard.
If there’s standing water by your tank, then it might mean the tank has a leak.
5. Bad Odors
The smell of sewage is like rotten eggs.
If you smell it, then it means something is wrong with your septic system.
The odor can stem from anywhere, but it usually lingers around your plumbing.
You can also smell it outside, particularly where the tank is located.
Bad odors might mean that you only need your tank emptied.
It could also mean that the solid waste is unable to move from your plumbing into the tank.
If something is clogging it, then you’ll smell the solid waste until it pushes through and ends up in the tank.
6. Spongy And Lush Green Grass
You may love the sight of lush green grass.
However, it may indicate that your septic system has a problem.
Grass grows well when it’s fertilized.
The material inside of septic tanks makes for great fertilizer.
Unfortunately, it means that the solid waste inside of the tank is leaking into the soil.
This is a health hazard, and it means that your septic system is no longer containing solid waste.
A pipe may be broken or the tank itself is leaking.
You can tell if the problem comes from your septic system based on the location of the spongy and lush grass.
It’s the grass around the tank and in the drain field that should worry you.
7. Algal Blooms In Water Sources
If your yard contains a pond, lake, or some other kind of natural water source, then you may notice the growth of algal blooms.
These algal blooms are a result of sewage leakage.
They thrive in the presence of bacteria and microbes that exist within the tank.
It also means that sewage is leaking into the water source.
Consult a professional to find out the best way to fix the problem.
8. Increased Nitrates And Coliform Bacteria In Wells
One final sign that your septic system needs repair is the presence of nitrates and coliform bacteria in your well’s water.
Your well water receives its supply through groundwater.
If your septic system is leaking, then the bad bacteria can enter your well water.
A functioning septic system removes this type of bacteria before it enters your well.
Regular testing of your well water can help ensure it’s safe to drink and use.
How To Prevent Septic Tank Failures
There are few steps you can take to prevent your septic system from failing.
1. Decreased Use
Using your septic system less can increase its lifespan.
The less use that it has, the less the parts wear down.
Limiting water usage and finding other ways to dispose of trash and waste can help.
2. Regular Inspections
Nothing prolongs an appliance’s life more than regular maintenance.
While your tank likely needs pumping every few months or once a year, you should also use that time to inspect it.
A professional can repair parts and keep them running smoothly.
When your septic system runs efficiently, it puts less wear and tears on its parts.
As a result, it lasts longer.
3. Soil Conditions
Whether you’re moving into a new home or thinking about changing the location of your septic tank, you need to consider the soil’s conditions.
One of the most important factors is the presence of flooding.
If the soil floods, then it can damage your tank.
Consider placing the tank in an elevated area.
Another condition is the presence of microbes.
These microbes will kill the bad bacteria inside the wastewater.
If there aren’t any microbes there, then there’s nothing to filter the wastewater.
4. Regular Tank Pumping
Along with frequent inspections and maintenance, you should also have the system pumped often.
Your tank starts to have problems if it’s bursting at its seams.
Wastewater is unable to flow out of the pipes as well.
More solid waste clogs the system.
It can spell a recipe for disaster.
Having the system pumped out often can ensure everything moves like it’s supposed to.
5. Not Flushing Non-Biodegradable Materials
A new problem that is causing vexation in plumbers is the habit of flushing non-biodegradable materials down the toilet.
Wet wipes, baby wipes, and similar products are the main culprits.
The problem with these materials is that it’s impossible for the bacteria to break them down in the tank.
As a result, they clog up the sewer lines and cause serious harm to the rest of the system.
They also remain in the tank for years because nothing breaks them down.
Throw them in the trash to keep your septic system healthy.
A septic system that sits unused can last for several years.
Certain materials, like concrete, can allow the septic system to potentially last indefinitely.
A few factors can cause the used or unused septic system to age prematurely.
There are signs that can indicate you have a problem with your septic system.
Preventing certain habits and being aware of your system’s health can help it last even longer.