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Discover How & Why Tree Roots Can Cause Sewer Damage

The Roto-Rooter sewer cleaning machine got its name because it rotates a spinning cable with sharp blades on the tip through underground sewer pipes cutting away tree roots that can clog a sewer and cause sewage backups. Tree roots might seem like fragile little stems but they can grow to monstrous proportions and are incredibly resilient and strong! Roots can cause lots of damage to underground pipes but it takes a long time for the damage to show itself.

Thirsty trees and shrubs send tiny feeder roots out through the soil in search of water and nutrients. When the roots find water, they begin sipping it and pumping it back to the tree. One of the easiest places for roots to find water is an old sewer pipeline made of clay, concrete, iron, Orangeburg or other imperfect materials. When the sewer pipes were laid, their sections were joined together tightly to prevent roots from getting inside. Each section of pipe has a male end and a female end. Clay and concrete were usually “pitched” together using tar pitch or a similar material that helped seal the joints. The problem is that the seals don’t last forever and as the seals fail over time, those little feeder roots work their way inside to infiltrate the sewer pipe and discover the moisture and nutrients they were sent to find. Mission accomplished!


In time, those little roots grow fat and happy. They soon become the tree’s most important lifeline to a seemingly endless supply of water and waste nutrients (think fertilizer). As a result, the roots grow larger so they can deliver more and more water to the growing, healthy tree. As roots grow larger in diameter, they put a strain on the pipe joints and gradually break the clay, concrete or other materials away. To visualize how they do this, think of how many times you’ve seen a tree root push up a section of sidewalk. It’s a slow but steady pressure that gradually defeats the concrete and shoves it aside. The same thing happens to your sewer pipe. As the holes in the pipe get bigger, more water and sewage leaches out of the pipe into the surrounding soil. The soil supporting the pipe begins to erode and the pipe sections start to move around in the watery loose dirt. Pretty soon, the once reliable pipeline starts looking like a loose collection of pipe sections that are only semi-connected as more and more roots infiltrate the pipe and compound the damage. To make matters worse, the roots spread out like nets and catch toilet paper and waste until a clog forms.


A Roto-Rooter plumber can easily cut away young tree roots and restore flow in your sewer. Mature roots become more of a challenge but we can usually cut through those too – up to a point. Once the root mass starts looking like a tree limb, even the mighty Roto-Rooter machine can’t always cut through. And by that time, chances are good that the pipe sections are so damaged and misaligned that the sewer has just about had it anyway. Toilets stop flushing and drains stop draining and sewage has nowhere to go but into a bathtub or sink. Remember, sewers are designed to be a sealed system. If they are leaching sewage into the soil, it’s an environmental issue. Annual sewer cleanings can keep a sewer line open for years if a homeowner keeps up with root growth but eventually, the sewer will reach the end of its life and it has to be replaced.


Clay piping has a long history. There are examples of clay pipe dating back as far back as 4000 B.C. in Babylonia. Various types of clay pipe have been used to make sewer lines ever since. The newest Vitrified clay pipe has a ceramic like finish, is strong and fits tighter at the joints than the older clay piping but ask anyone involved in plumbing services and they will tell you it is harder to work with than PVC and it's very heavy, requiring heavy hauling trucks to move it around.

Clay pipes, sometimes called terra cotta, are very susceptible to root intrusion and leaks. Once those tiny tree roots invade the pipe via a loose joint, the roots grow bigger and eventually break away the clay much like tree roots raise concrete sidewalk panels. Old crumbling clay pipes are responsible for many plumbing problems in homes and businesses across the country, resulting in expensive sewer repair work and plenty of business for plumbing contractors.

It is surprising how much clay sewer pipe is still in service today, though not very reliably. Local plumbing companies replace it daily with more reliable PVC and other materials that last longer while resisting leaking and root intrusion.


Tree roots are to blame for millions of sewer clogs each year but too often homeowners swear revenge against the offending trees then follow through by cutting them down. But that’s an extreme reaction and not necessary! Your sewer pipes can coexist with your trees – and we’re not just saying that because we’re in the plumbing and sewer cleaning business and our name is Roto-Rooter. We love trees, and not just because they help us make money! They’re beautiful and they’re good for the environment.

Modern trenchless sewer replacement methods allow us replace underground sewer pipes without digging up your yard. And the sleek new pipeline that we use to replace your old broken sewer pipe is more or less permanently impervious to root infiltration. It’s immune, untouchable and you’ll never again need to worry about a sewer backup caused by tree roots the way you did with old clay, Orangeburg, concrete or iron pipes. The manufacturers of some of the modern plastic pipe estimate that the new plastic pipelines will probably last 100 years! Pipe bursting and pipe relining is something we’ve been doing at Roto-Rooter for more than a decade so we’re well versed on its merits. The cost for trenchless sewer replacement is a bit higher than a traditional sewer excavation job but it’s still cheaper than having a few trees removed and you won’t need a year to get your lawn back in order. For the most part, there won’t be much physical evidence that our crew was ever there.

But chances are you don’t need to replace your sewer at all. If the pipe is still in fair condition, you can manage tree root infiltration by calling Roto-Rooter when you start to notice more than one drain in the house draining slowly. We’ll mechanically clean the line and remove all roots and obstructions. Having more than one slow drain in the house is an early warning that a sewer backup is coming. Better yet, if you know your home experiences a sewer backup about once a year, call us, we’ll put you on an annual schedule and remind you when it’s time for your annual sewer cleaning. We can do this at whichever intervals meet your needs. The cleanings are affordable and you won’t have to sacrifice the beautiful shade trees in your yard that are probing your sewer line for water and nutrients.


Tree roots will seek out water and nutrients wherever they can to survive a drought. Roto-Rooter plumbers often see a strong uptick in the number sewers clogged with tree roots during exceptionally dry seasons. Why? Unfortunately, for many homeowners, when trees aren’t getting enough water from regular rainfall, they’ll send feeder roots through the soil looking for moisture and nutrients. Often, the path of least resistance leads to underground sewer pipes.

Roots might be slow, but they are very powerful. Over time, they can infiltrate clay or concrete sewer pipes at the joints and gradually fill the pipe with roots. As these roots continue to grow, they begin to catch waste and toilet paper until a sewer clog forms and the pipe can no longer drain. These clogs then cause drains in the house to backup with sewage, creating an awful and disgusting mess.

To keep tree roots at bay and prevent sewer clogs, sewer pipes in the vicinity of trees, need to be cleaned and regularly maintained. How often depends on the condition of the pipeline, how many trees are nearby and the material the pipeline is made of. Modern plastic pipes fuse together more tightly than clay, concrete, or iron, meaning they are less susceptible to root intrusion unless they are already damaged or separated.

On top of household backups, tree roots can cause ongoing physical damage to underground pipes if they aren’t dealt with promptly. When tree roots begin to grow larger at the point of infiltration, they can slowly force pipe joints apart and even break away pieces of clay and concrete to cause large holes in the pipe. Not only does this type of damage allow even more roots inside, but it also can allow raw sewage to leach into surrounding soil.

The sewer and drain experts at Roto-Rooter are ready to resolve any sewer and drain issue you might have. If you’re concerned about the effect of dry weather on your underground plumbing, watch for clues such as multiple slow drains in the home. Then, give your local Roto-Rooter plumber a call for a video line inspection that can identify roots or other blockages in your pipes and solve the problem.


In the fall, roots can return very quickly as the trees are creating more roots in preparation for the winter storage. The real problem is the roots were removed from the inside of the piping, but the tap roots are still in the hubs of the pipes. Snaking a line can only reach the hairlike fibers of the roots in the pipe. The tap roots are not extended into the pipes but run alongside the pipe and enter through the concrete, tar or lead joints. Once inside the joints they draw in the liquids and waste from the sewage and increase in size. This is their food source.

There are a few options to this residential plumbing problem. First, have the line cleared again if it is under warranty. After the sewer cleaning, put a root destroyer down the line. This is usually copper sulfate, which will cause the roots in the joints to die and rot. The roots will come back, but it will take much longer.

Have a one of your local plumbers come out to inspect the line with a camera. The video camera will allow you to see if the pipe is broken. If broken, you will either have to have that section repaired, or if the damage is extensive, you will need a new liner put in the old pipe. In any case, a camera line inspection will let you know if a proper sewer cleaning was performed and how long it will be before you need extensive repairs. This gives you a way to plan for the future, instead of having a collapsed line and scrambling to the first-plumber you can for help.

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