Often, yes. You can usually keep the tree if you fix the sewer line. Roots can't crack a sound pipe; they get in through cracks and leaky joints that already exist. Repair or replace that section with tight-jointed pipe and the tree can stay. Cutting roots out alone buys time, since they grow back.
Why did the roots get into the pipe?
Because the pipe was already leaking. NC State Extension puts it bluntly: "Tree roots cannot create cracks in your sewer pipe - they can only exploit existing cracks or gaps." NC State adds, "So if you have tree roots in your sewer pipe, that means you had a leaking sewer pipe before the tree roots got there."
Roots follow moisture. The City of Traverse City's utility explains that "Tree roots are attracted to the water vapor leaving the pipe and they follow the vapor trail to the source of the moisture, which are usually cracks or loose joints in the sewer pipe." The International Society of Arboriculture says "Older cement, clay, or cast-iron pipes that have degraded may develop leaks. Moisture from the leaks attracts tree roots, which can penetrate and expand the cracks, further damaging the pipes."
Phoenix sees the same thing in its own lines. The city's sewer FAQ calls "roots from trees and invasive shrubs, such as oleanders" the second biggest problem it deals with, after grease, and says roots "can find their way through the pipe joints or other openings and form a root ball once inside the pipe."
Pipe material matters. Traverse City says clay tile pipe "was easily penetrated and damaged by tree roots," while "PVC pipe is more resistant to root intrusion because it usually has fewer joints." See the signs of tree roots in a sewer line and how long a sewer line lasts.
Would removing the tree solve the problem?
Not on its own, and it may not even be the right tree. Roots travel a long way. Traverse City says "As a general rule, tree roots will extend up to 2.5 times the height of the tree, and some species of trees may have roots extending five to seven times the height of the tree." The ISA says roots "can extend out farther than the height of a tree." The University of Arizona says most tree and shrub roots sit in the top two feet of soil and "extend up to 3 to 5 times the width of the canopy." A neighbor's tree, or a hedge of oleanders, can be the one in your pipe.
Dry weather makes it worse. Traverse City notes that "During drought conditions and in winter, tree roots travel long distances in search of moisture." NC State says "Tree roots can reach from one end of the yard to the other in search of moisture." In the desert, a leaking sewer joint may be the wettest soil in the yard, which is exactly what roots are looking for.
NC State Extension makes the same point about distance: "planting a tree five feet closer to or further away from a sewer line won't make a difference." It says the reason not to plant directly over a sewer line is "so that the tree doesn't have to be cut down when that sewer line needs maintenance."
So the leak stays, and so does the risk from every other root in the yard. Removing a tree can still make sense when it sits right on top of a line that has to be dug up, when it's damaging a foundation, or when it's a poor choice for the spot anyway. But it's a landscaping decision, not a sewer fix.
What fixes the pipe so the tree can stay?
Closing the openings the roots use. The options, from shortest-lived to longest:
| Approach | What it does | How long it lasts |
|---|---|---|
| Cutting roots out | Clears the clog | Temporary; roots grow back |
| Root control treatment | Kills roots inside the pipe | Temporary; needs repeating |
| Spot repair | Replaces the cracked section or joint | Fixes that spot only |
| Lining the pipe | Puts a new jointless pipe inside the old one | Seals the whole lined length |
| Replacing the line | New pipe with tight joints | Longest-term fix |
Cutting. A plumber can cut roots out with a cable machine or a water jetter, and that restores flow right away. But a California sewer agency manual warns that "cutting roots actually encourages root growth on live trees and shrubs, and then the roots grow back more dense and damage the pipe." Cutting is a way to buy time, not a cure. See whether hydro jetting keeps roots from coming back.
Repairing or replacing. A camera inspection shows where the roots are getting in. One bad joint can be fixed with a spot repair. Many root-entry points along an old clay or cast iron line usually mean lining or replacing it. New PVC pipe with tight joints gives roots far fewer ways in, and the tree can keep growing above it. For how to choose, see tree roots in a sewer line: repair or replace and pipe bursting vs pipe lining.
### Do root barriers help?
They can, on new pipe. Kentucky's Sanitation District No. 1 says "If installing new pipe, consider using solid barriers such as plastic, wood, or metal." It lists chemical barriers too. A barrier won't do much for an old pipe that's already cracked, because the roots are after the moisture leaking out of it.
Are chemical root killers safe to use?
Some are restricted, so check before you pour. Copper sulfate is the old standby, and it's limited in places. California's pesticide rules say "No person shall possess for use or use a pesticide product containing copper sulfate for the control in sewers and drains, of tree or other plant roots" in nine Bay Area counties. We found no Arizona rule on it. If you use any root control product, follow its label exactly.
NC State Extension suggests trying foaming root killers first, naming products with sodium chloride, sodium bicarbonate, dichlobenil and sodium lauryl sulfate, and it describes dichlobenil as "less toxic than copper sulfate." It also warns against harsh drain cleaners "that can damage older sewer pipes, creating an easy avenue for tree roots to infiltrate."
Like cutting, chemicals treat the roots, not the crack. They make the most sense as upkeep while you plan a repair.
What should you plant near a sewer line?
Choose carefully for anything new. Phoenix's sewer FAQ says "Care should be taken to not plant a tree or large shrub too near your property line, over or near the sewer line or cleanout for your home, or close enough to your home where the foundation can be invaded by the roots." Sanitation District No. 1 recommends sticking with trees and bushes "that don't have aggressive root systems if planting near sewer infrastructure," and lists species such as poplar, cottonwood, willow and sycamore among those that could pose problems.
If roots keep backing up your line, HQ Plumbing & Air can run a sewer camera inspection to find where they're getting in and handle the repair, with 24/7 service across the Phoenix area.