3 Possible Reasons Why Your Septic Tank Is Clogged

Many homeowners confuse a clogged septic tank system with household pipe issues because the clog slows down the drainage system. But, it should be easy to differentiate the two since, with clogged septic tanks, every lower drain slows down at once. Usually, these drains include the basement floor drain and shower outlets.

Understanding why your septic tank clogs makes it easy to implement preventive measures. Find below three of the reasons why your septic tank system clogs.

1. Irregular Pumping of the Tank

You should pump your tank every 3-5 years after a thorough inspection. The pumping frequency usually depends on the following factors:

  • The amount of wastewater generated
  • The amount of solid waste generated
  • The tank size
  • Household size

The above factors play a significant role in forming the sludge and scum layers in the septic tank. With regular septic pumping services, you'll remove these layers before they clog the tank. 

Usually, septic technicians pump tanks when the difference between the sludge layer's top and the T-shaped outlet is 12 inches. They also recommend pumping when the difference between the outlet and the scum layer is 6 inches.

Always record every maintenance activity on your septic system to keep track of the process. In addition, regular inspection should help you track accurate measurements of the scum and sludge layers.

2. Tree Roots

Most homeowners prefer to shade the lawn with trees. But these trees can also damage drainage lines. Tree roots always search for water, and since drainage pipes convey wastewater to the septic tank, they fall prey.

If these pipes have holes, the roots penetrate and draw the water. Since the water contains nutrients, tiny tree roots grow through the pipes and into the septic tank. Within no time, the tank overcrowds and clogs.

3. Chemical Drain Cleaners

It is quite unfortunate that the cleaners you trust so much can clog your septic tank. Chemical drain cleaners may clear the blockage in your drain, but they also kill the beneficial bacteria in your tank. Since these bacteria break down the solid waste, their absence means a buildup of the sludge layer. 

 Bio drain cleaners are often better because they have no effect on the bacteria in the septic system. With eco-friendly cleaners, you'll also save on repair and pumping costs.


Proper maintenance is the best way to keep your septic tank system free from clogs. So first, always schedule a regular septic system inspection. Then, call reliable septic professionals for septic tank repair, pumping, and replacement services.