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How to Kill Roots in Sewer Pipes

Deep tree roots are naturally drawn to cracked sewer pipes. These compromised pipes leak water and nutrients into the soil, attracting the roots. Once a tree root finds its way into a crack in a sewer pipe, it will grow rapidly. Tree roots that grow large enough will block the sewer line and cause sewage to back-flow into your yard or basement. But although the problem may seem disastrous, you don’t have to kill the trees to kill the roots that have grown into your sewer pipes. A simple foaming septic root killer will kill interfering roots on contact while keeping the tree safe.

Pour the foaming root killer into the sewer system. The best method is to pour the root cleaner into your cleanout (the capped pipe on your property that directly accesses the sewer line). If you don't have a cleanout on your property, flush the foaming root killer down the toilet.

Turn off all the water in your home. Keep it off for at least one hour after the foaming root killer treatment.

Re-treat the sewer system with foaming root killer annually. Most foaming root killers kill roots and retard their growth, but other roots may find their way into other compromised sections of your pipes. Pre-emptive treatment is the best approach.

Home Remedy To Kill Roots In A Sewer Pipe

There might not be a more unpleasant experience than flushing your toilet, only to have all the contents back up onto your bathroom floor. A common culprit responsible for such backups is tree roots in your sewer line. But introduce even a tiny crack or fissure into a sewer line and tree roots can invade, grow and cause all kinds of havoc. A tree's roots can grow to up to three times the width of the tree's crown, so even if you remove all of the trees on your property in the vicinity of your sewer line, roots from your neighbor's trees might find a crack in your sewer line. A half-cup flushed down the toilet should be enough to treat minor root infestations, according to the Oklahoma Cooperative Extension Service. While copper sulfate is effective in killing tree roots in your sewer line, it is usually not an overnight process. Copper sulfate is used in certain pesticides to kill algae, snails and fungi. Only introduce copper sulfate through the toilet.


The amount of foaming root killer you need depends on the length of your pipes and the strength of the product.

Foaming root killer kills tree roots instantly, but it may take a few weeks for the roots to degrade enough to clear the blockage.

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