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How long do septic tanks last?

Septic tanks can have a life expectancy of 20 to 40 years, depending on the situation. They have been known to last less than 20 years and more than 40; however, if you are in a house that is 20-40 years old, then you may end up having to replace your septic tank in the coming years. Here is what you need to know about the average lifespan of a septic tank and leach field system.


Why do septic tanks need to be replaced?

The lifespan of a septic tank system can have a pretty wide range. There are a variety of reasons why your tank can need replacing. The tank could have cracked from the ground shifting or driving large machinery on top of it or the leach field. While the EPA states that the lifespan of a septic tank is 20 years, you may find that your tank needs to be replaced sooner, depending on the circumstances.

The type of tank material can also be a reason for your tank needing to be replaced. Concrete septic tanks will naturally corrode and wear down over time. Plastic septic tanks, much like holding tanks, can crack, and steel septic tanks can rust.

No septic tank is 100% perfect, and depending on your year-long weather conditions, you may live in a climate that is harsher on your septic system and drain field.

If it’s an older house, the tank may just be worn out. This can happen over time.

Need to replace you tank? Find out the difference of a septic tank vs cesspool, or septic tank vs holding tank to see either or better for your house.


How to tell if your septic tank needs to be replaced

If you are starting to have septic tank problems and you are in an older house, you may be at the point where you need to get a new tank.  Here are some signs to look out for when it comes to replacing your septic tank.

  • The grass is green around the tank. This is a warning sign that your tank is likely cracked and needs to be replaced. A septic system is a closed unit, and the grass shouldn’t be any greener around your tank than it is in any other part of the yard. The elements in household waste are similar to the same compounds found in fertilizer which can cause the grass to turn green if there is a crack in the tank because the soil conditions are more favorable for green grass.
  • Septic tank smells start to show up in the house. If you have a foul odor, it could mean that your septic tank is full or the pump out to the leach field is broken, and things are starting to back up. In that case, you may hear the next issue.
  • The Septic tank alarm goes off. This one is an urgent call, and you need to deal with it immediately. This means that there is something wrong in the tank, and the level of waste in the tank has built up to an unsafe level.


How to extend the life of your septic system

If you want to keep your septic system operational as long as you can, there are a few things you can do.

  • First, get your septic tank pumped regularly.
  • Second, avoid trees being planted around your drain field. The roots can get into the pipes and clog them, giving you issues.
  • Third, don’t drive heavy machinery on top of your tank or leach field. This can crush the pipes and cause the water to back up, leaving you to repair or replace your leach field.
  • Use toilet paper that is septic safe.


Final thoughts on your septic tank system and drain water systems lifespan

Just because you are having septic tank problems doesn’t always mean it’s time for a septic tank replacement. There could be other issues involved. The first thing to do is get your septic tank pumped. Ask the septic service technician if he notices anything different on the tank and take notes. You should also ask if he knows of anyone who does septic systems maintenance and repairs. It could be something as simple as your septic tank filter being plugged or a wire in the tank rotting away in the junction box.

The point is to make sure to seek expert advice before you decide to replace your tank.


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