Prevent Tree Roots in Sewer Lines

tree roots

Irrespective of the size, a tree can provide both beauty and a sense of tranquility. However, they also come with their own set of responsibilities including maintaining the integrity of its roots.

Sewer lines provide an abundant source of water, nutrients, and oxygen that plants need to grow. The roots quickly worm their way into pipes after being attracted by the moist environment. Prevent tree roots from entering into your sewer line by

  • replacing vulnerable pipes
  • landscaping carefully
  • planting sewer-safe trees

Tree roots in sewer lines are among the most common causes of blockages, broken pipes, and numerous other plumbing problems for homeowners. It can cost thousands of dollars to fix drain pipes that are damaged by roots. Thus, it is crucial to prevent tree roots from growing into sewer lines.

The question is, how do you do this? 

You can use integrated root control approaches to eliminate this problem when it occurs, or even before. 

You can also create barriers between the roots and sewer lines using chemicals, wood, or metal. Ensuring early detection and handling of issues is the most important thing to do if your susceptible to these issues. 

How tree roots get into sewer lines

Well-kept drain pipes are usually safe from tree root intrusion. However, over time, pipe fittings can become loose, clay pipes can develop tiny cracks and fissures, and old lines become worn out. This can lead to water leaks.

When roots come into contact with the leaks, they multiply at the spot and penetrate damaged pipes to further access the available water, oxygen, and nutrients.

The extent of root invasion depends on the sewer line condition, soil condition, type of tree, and other environmental factors.

Dangers of tree roots intrusion

The intrusion of roots into sewer lines can result in structural damage, sewage stoppage overflows or backups, and the formation of septic pools or soggy grass.

Common signs of this are foul odor, exfiltration of sewage into soils around the leaks, and contamination of clean water around the leaks resulting in health risks. 

In bad scenarios, basements can back up with sewage, leading to costly repairs and disinfecting.

How to detect and repair tree roots damage

Tree roots are a familiar problem for homes with sewer lines laterally hooked to a municipal sewer system. If you want to confirm a tree roots problem or determine the extent of it, then you should consider hiring a professional plumbing company.

Professional plumbers use advanced video equipment to inspect the sewer line to identify potential damage to the pipes.

They then give recommendations on the best way to fix the problem depending on the extent of the damage. For example, you can repair the pipes by lining them with durable, seamless products that create new pipes inside the old ones. See the video below:

However, if the damage is significant, you may need to replace the existing lines with new long-lasting root-resistant ones.

Drain flies in your home can be a sign of cracks in your main sewer line. Typically, flies and other insects are attracted to the sewage buildup. There, they begin to multiple and travel until they find ways into the home via basement drains, bad toilet seals or dried up drains (no water in the p-trap).

Warning signs of tree roots in sewer line pipes

The effects are often not perceptible until it is too late so here are some telltale signs that will help you identify the root damages:

  • Frequent drain clogs: While drain clogs are pretty standard, frequent clogs may be a good indication of a bigger problem. Root damage may result in clogged sewer lines, leading to overflowing or slow-flowing drains. 
  • Water backups or overflows: These are usually signs of a clog, inefficient drain, blocked or collapsed pipes. Water should comfortably pass through your drain pipes. If it doesn’t, this may be because of tree roots in sewer line pipes.
  • Gurgling toilet drainage: Gurgling sound coming from your toilet when you flush another indication that there is a blockage preventing the contents from passing through the pipes with ease.
  • Foul odors: If you smell rotten eggs or sulfur, you could have a serious sewer problem. Foul smells coming from your drains are an obvious sign that you have a problem with your plumbing.
  • Sinkholes: If you notice unearthed ground and pool of collected water in your garden, consider calling a professional to rule out any damage,
  • Drain flies: clogged pipes provide the ideal breeding and feeding ground for these flies. Hence a large number of them is a good indicator of a clog in your pipes.

Knowing the early signs of tree roots in the sewer lines damage is good for preventing further damage.

The presence of drain or phorid flies

Neither of these pests are easy to deal with. They tend to appear at random, and can quickly get out of control.

Phorid flies, which are different than drain flies, can be an indicator of a leak beneath your slab or crawl space. 

Don’t sweat just yet! They can also be from dead mice, clogged drains and a host of other issues.

However, if you already meet the criteria for other sewer line breaks or intrusion symptoms, this could be the reason. 

Phorid flies will breed in the ‘gunk’ that runs through the sewer. If you have a break, this leaks out and attracts all types of pests, including phorid flies.  

Drain flies are attracted to areas with organic buildup as well. They lay eggs and breed in the material, appearing usually when they are adults. They can also be spotted in drains during larval phases and look like worms. 

There are many treatments available for these pests, but until you find and remove their breeding site, the issues will continue. In the case of a break under your slab, you might need to work with bot ha plumber and exterminator to properly treat the issue.

How to get rid of tree roots in sewer lines

Root removal is an arduous and complex task. In order to make sure that the separation between the sewer and tree roots is complete, you will need to use a mechanical force.

Mechanical root removal tools are often used by professionals in the industry because they have been designed to cut through roots quickly and efficiently.

A professional can usually do this in a couple of hours, while it may take up to a day for amateurs with power tools.

There are different integrated root control approaches to use including: 

  • Mechanical Control: You remove the roots mechanically by cutting through them with augers, rooters, drill machines, rodding machines, jetters, and winches. Blast the remaining root blockage apart with hydro-jetting equipment to wash away the debris and create space for repairs. It is, however, a temporary fix as the roots might grow back after a while.
  • Physical control: Once roots have begun finding their way into drain pipes, you can physically handle the problem by replacing or lining the pipes or removing the tree.
  • Chemical control and sewer salts: You can use herbicides or rock salt to eliminate roots in sewer lines. However, when using chemicals, it is important to keep in mind that some substances can cause corrosion weakening the pipes even more. 

It’s crucial to keep in mind that simply removing the tree roots does not take care of the problem entirely. You can schedule regular maintenance to prevent the problems from recurring if you have a large tree combined with old sewer lines. .

How to prevent tree roots from growing into sewer lines

The primary way to handle tree root damage is to prevent it from occurring in the first place. Steps to take include:

Landscaping carefully

Landscaping plays a significant role in root penetration. If you plant trees near your sewer line, you are more likely to have roots invading your pipes. Prevent sewer line and tree roots contact by considering how your landscaping plan. Building lines away from sewer lines prevent the infiltration of roots.

Also, before doing any new landscaping, locate your sewer lines. Do this with the help of the local public works department or a professional plumber. Knowing where your underground pipes run will assist you in planning your planting better. 

Plant sewer-safe trees and shrubs

Choose your trees wisely. Small slower growing trees such as the white fringe, Amur and Japanese maples, dogwoods, and redbuds are less likely to damage your lines. They grow at a slow rate and have more petite root balls or spread.

You should plant trees further away from the sewer lines if you prefer fast growing trees. Also, schedule regular plumbing inspections for early detection if the roots invade your sewer line.

Create barriers between roots and sewer lines

Use slow-release chemicals such as potassium hydroxide and copper sulfate that are effective biocides to repel root growth.  You can also use wood or metal barriers placed 6 – 12 inches further into the ground than the pipes to prevent roots from growing into pipes.

Creating barriers allow you to enjoy all the befits of having trees around your home while protecting your sewer lines as well.

Replace vulnerable pipes

For old houses, consider replacing concrete and old clay pipes with seamless high-density polyethylene pipes in a trenchless pipe process.

These will have a much longer service life and are less likely to experience tree root issues.

Schedule regular inspection and maintenance

Cleaning your sewer pipes regularly and inspecting the structure of pipes will help you avoid significant sewer repairs. With an annual inspection, you can get peace of mind that blockages are not threatening your plumbing system.



Take measures to protect your sewer lines from tree roots and save thousands of dollars from future repair costs. Also, schedule regular inspections and maintenance to ensure that you have well-kept pipes and efficiently flowing drainage systems.

Preventative plumbing maintenance has proven to be more financially manageable in the long run, securing your home’s value.

Article Reviewed By:

Dakota S. MS in Biology

Dakota holds a Masters of Science in biology/biological sciences, with an emphasis on entomology and parasitology. An accomplished researcher and writer, Dakota has completed numerous research papers and published peer-reviewed literature. Notable accomplishments include the study and documentation of new structures not previously known to be fluorescent in Ixodida (ticks).