How to Keep Roots From Growing in Sewer Drain Pipes


If you have tree roots that grow into sewer drain pipes, you have a serious problem. Roots find cracks in the lines and sense the water vapor that is leaking into the soil. Because roots seek out water, they grow toward it and make their way into the pipes. They expand as they mature and cause blockages and backups in your sewer system. If they are not disturbed, the roots will completely fill the pipe. To keep roots from growing in sewer drain pipes, you need to be smart about where you plant trees. If roots still manage to reach the sewer tank, there are some things you can do to fix the problem.

Step 1

Find out where the sewer lines are around your home. A plumber can assess the situation before planting. You can also get a good idea by looking at the trees and estimating the root growth to be 2.5 times the height of the tree.

Step 2

Plant a tree that has a smaller, non-aggressive root system. These include crabapple, scarlet oak, white oak, cherry tree and dogwood. Do not plant trees such as pine, maple and willow near septic systems. Measure before planting and make sure to put the tree far enough away from sewer lines so the roots can grow without hitting the pipes.

Step 3

Install a root barrier to protect sewer drain pipes from tree roots. They resemble panels and are available nurseries. Dig 3 feet from the septic system to a depth of at least 5 feet. Put the panels in the ground and cover them with soil.

Step 4

Use chemicals to kill roots that have already grown into sewer drain pipes. Pour drain-cleaning products containing copper sulfate down the bathroom drains. Do this in the spring and fall to break up the clogs caused by roots.

Step 5

Place fabric or rubber that is filled with the chemical trifluralin between the tree roots and pipes. The chemical is inside time-release pellets. To accomplish this, you have to dig until you find the spot where the roots have grown into the drain pipes. Insert the fabric along the side of the drain pipes, following manufacturer instructions.

Step 6

Call a plumber to replace the sewer drain pipes or patch cracks. This will keep water from escaping, but it's an expensive proposition.

Tips and Warnings

  • Avoid applying too much copper sulfate because it can be harmful to the environment and kill the tree. Be careful when handling chemicals.

Things You'll Need

  • Smaller trees
  • Shovel
  • Root barrier
  • Copper sulfate products
  • Trifluralin


  • Washington State Department of Agriculture
  • Inspectapedia: Guide to Planting Trees or Shrubs Over or Near Septic System Components
  • Paso Robles: Tree Roots vs. Sewer Lines

Who Can Help

  • Vespro: Root Solutions-Root Barriers
Keywords: keep roots away from sewer drain pipes, block roots from sewers, tree roots

About this Author

Kelly Shetsky has been a broadcast journalist for more than 10 years, researching, writing, producing and reporting daily on many topics. In addition, she writes for several websites, specializing in medical, health and fitness, arts and entertainment, travel and business. Shetsky has a Bachelor of Arts in communications from Marist College.