How Long Do Septic Tanks Last? Here’s the Average Lifespan
Maximize the lifespan of your system
Whether you’re installing a new system or wondering whether it’s time to replace your current one, you’re likely wondering: How long do septic tanks last? The average lifespan of a septic tank is between 15 and 50 years. Type, usage, size, and even the soil type in which it rests all play a role in a septic tank’s longevity. However, knowing how the system works and following proper maintenance techniques can help you maximize its potential.
How Long Does a Septic Tank Last?
The primary factor that determines how long a septic tank can last is the material it's made of. In some cases, where the tank is concrete, properly installed, and expertly maintained, homeowners can get well over the average lifespan out of their systems. However, most systems last between 15 and 50 years, max. Concrete, steel, and plastic or poly are the most common materials for the various types of septic systems available.
| Septic Tank Material | Average Lifespan (Years) |
|---|---|
| Concrete | 40–50 |
| Plastic | 30–40 |
| Steel | 15–20 |
Factors Influencing How Long Your Septic Tank Can Last
Several other factors also influence how long your septic tank and system can last. Here are the big five.
Material
Provided proper installation and maintenance are a given, concrete septic tanks outlive the other common septic tank materials, including steel and plastic. Concrete is more durable than the others, and because of its immense weight, it's less prone to damage by ground movement or soil weight.
Concrete is also the most expensive option for installing your system due to the need for extra labor and heavy lifting equipment during the process. However, a concrete septic tank can last between 40 and 50 years. A plastic option can last up to 40 years and a steel version up to around 20 years.
Installation
Regardless of the type and material of the tank you install, proper installation is a must to maximize its lifespan potential. Hiring a local septic tank company with area-specific knowledge and skills is essential to getting the most out of your system.
Soil Type
The type of soil your septic tank rests in can affect its lifespan. While concrete septic tanks outperform other tank materials where the groundwater table is high, plastic ones perform better and won't corrode in highly acidic soil.
Usage
It's no surprise that the more usage your septic tank sees, the more strain the system must endure, which can reduce its lifespan. Installing the proper size system for your home's needs is crucial for maximizing its number of usable years.
Maintenance
Maintaining your septic system to the best of your ability is the best way to ensure its longevity. A septic system inspection costs between $200 and $900 and is well worth spending every three to five years. Your inspector can check if the septic tank is full and advise how often to pump your septic for the best results and a long lifespan.
Pumping your septic tank every three to five years is one of the most important septic maintenance tasks. When you combine that with flushing only approved items (toilet paper and waste) and avoiding driving over your drain field, you have a recipe for a long-lasting septic system.
Signs It’s Time to Replace Your Septic Tank
While only your septic system professional can tell for sure if it's time to replace your septic tank, there are a few signs that the time is approaching.
Your plumbing is experiencing backups or draining slowly.
Standing water or odors are lingering around your drain field.
The vegetation in and around your drain field has a sudden growth spurt.
Bubbling or gurgling sounds are coming from your plumbing systems.
Your system is older than its expected average lifespan.
How to Increase the Lifespan of Your Septic Tank
The more you can avoid putting non-septic-friendly materials and substances into your system and practice efficient water usage, the longer your system will last. Additionally, the better your maintenance plan, including regular inspections, pump-outs, and repairs as necessary, the longer it will be before you need to replace the system.
Warranties for Septic Tanks
Product warranties for septic tanks come primarily from the manufacturer and cover material defects and general system operation. Many installers also warranty the installation, making shopping around essential.
In some cases, such as buying or selling a property, purchasing a home warranty from a local provider can be worth it to cover some repair expenses. However, it's essential to read and understand the fine print in your contract before signing up for a plan. Home warranty plans have strict guidelines for what is and isn't covered.
Repairing vs. Replacing Your Septic Tank
Deciding whether to repair or replace your septic tank requires professional insight and a thorough inspection. The cost of septic tank repair averages between $630 and $3,040, while the price of a new system is between $2,910 and $18,600. So, it is practical to make repairs instead of replacing the system.
However, if your septic system requires frequent repairs or if your system is nearing the end of its expected lifespan, replacing it is often the better option.
Frequently Asked Questions
The cost of installing a new septic system on a residential scale is between $5,000 and $12,000 on average. However, replacing an existing system can come with additional costs as well. Removing and disposing of the existing equipment will add an extra $45 to $200 per hour, and any necessary changes to the landscaping to accommodate the new system and meet updated building codes can add to the cost.
While abandoning a tank without treating it and following strict rules is illegal, there are several other ways to dispose of an old septic tank. One standard method is to pump out and crush the tank where it rests and bury it in the soil. Another is to remove it and transport it to a landfill. Finally, if abandonment is the best option, your contractor must pump out the tank and fill it with inert material, such as sand or concrete, depending on local regulations.
- How Often Does a Septic Tank Need to be Inspected?
- What to Know About Installing a Small Septic System for One Toilet
- What Is a Septic Tank and How Does It Work?
- How to Find Your Septic Tank in 5 (or Fewer) Simple Steps
- Are Septic Tanks Bad? Pros and Cons to Consider Before Moving Into a House With a Septic System
- What to Do After Your Septic Tank Is Pumped: 4 Top Septic Maintenance Tips
- How to Check If a Septic Tank Is Full: 7 Easy Ways
- Here’s What to Put in a Septic Tank to Break Down Solids
- How Deep Is a Septic Tank and Why Is It Buried in the First Place?
- How Often to Pump a Septic Tank: What You Need to Know
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