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How Long Do Septic Tanks Last?

Everyone who owns a septic tank has wondered: how long do septic tanks last? After all, eventually you will have to replace the tank. The answer depends on what material your septic tank is made of and whether it’s been properly treated and maintained. We’ll explain how long you should expect your septic tank to last and how to maximize its life span below.

Average Life Span of Septic Tanks

Here’s the average life span of each type of septic tank:

  • Steel: The average lifespan of a steel septic tank is 15 to 20 years. While steel is a strong material, it typically rusts when used as septic tank, which gives it a much shorter lifespan than other septic tank materials.
  • Concrete: The average lifespan of a concrete septic tank is 40 years. Concrete isn’t vulnerable to rust and is strong enough to handle most pressure, like that from traffic.
  • Plastic: The average lifespan of a plastic septic tank is 30 years. Plastic tanks are more vulnerable to stress and more challenging to install, which can shorten their lifespan.

While this is a general guideline for how long your septic tank should last, there are many factors that can limit it’s lifespan. Soil type can contribute to early problems. Highly acidic soil can eat away at plastic and metal tanks. Plus, traffic over the septic tank can crush a plastic tank. Environmental conditions (such as earthquakes) can reduce any tank’s life.

Choose a New Septic Tank

It’s important to choose the right septic tank material for your specific location and needs to maximize it’s life. It’s best to work with a plumbing professional to make this decision. Once you’ve chosen, you also need to keep the tank properly maintained.

Extend Your Septic Tank’s Life

The more life you get out of your septic tank, without compromising its effectiveness or safety, the less your tank will cost. Therefore, it’s in your best interests to keep your tank well maintained. Here are a few things you can do to ensure you get a the most life out of your septic tank:

  • Pump regularly: To avoid corrosion and stress on the septic tank, regular pumping is necessary. If you tend to let your tank go too long without being emptied of it’s liquid, you are likely cutting into its lifespan.
  • Protect from trees: If you have trees near the septic tank, or your sewer lines, it’s critical to prevent their roots from interfering with the system. Tree roots can crush sewer lines and do damage to sewer tanks over time.
  • Proper drainage: If the ground is retaining too much water, the pressure can force lighter tanks up, often breaking the pipes connected to it. This is a more common problem with plastic sewer tanks.

How is Your Septic Tank Doing?

Most septic tank owners don’t know how their tank is doing or if it will need to be replaced soon. The good news is any plumber who offers septic services can let you know how long your septic tank is likely to stay in good condition, or what you need to do to improve it’s lifespan.