Tree Roots and Sewer Lines in Dallas: What You Need to Know

If you have mature trees in your yard and you are starting to notice slow drains, gurgling toilets, or sewage backups, tree roots may be the cause. Root intrusion into sewer lines is one of the most common plumbing problems in older Dallas neighborhoods — and it is almost always preventable with the right tree choices and maintenance.

Roots do not punch through solid pipes. They find their way in through existing cracks, loose joints, or deteriorated sections — and older clay or cast iron pipes common in Dallas homes built before the 1980s are particularly vulnerable.

Once a root finds a small opening, it follows the moisture and nutrients inside the pipe. Roots can grow to fill the entire pipe diameter, eventually causing complete blockages or pipe collapse.

High-risk trees near sewer lines:

• Willows — The most aggressive root system of any common landscape tree. Never plant willows near utilities
• Silver maples — Fast-growing with wide-spreading, shallow roots
• Cottonwoods — Native but extremely aggressive roots
• Bradford pears — Shallow root systems that spread widely
• Sycamores — Large root systems that seek water aggressively

Lower-risk trees:

• Live oaks — Deep taproots, less likely to invade shallow utilities
• Cedar elms — Moderate root spread, generally manageable
• Crape myrtles — Small root systems, rarely a problem for utilities
• Desert willow — Small tree with non-aggressive roots

• Slow drains throughout the house (not just one fixture)
• Gurgling sounds from toilets or drains
• Sewage odors in the yard
• Unusually lush, green grass over the sewer line (roots are fertilizing the soil)
• Recurring drain clogs that come back after clearing

The only way to confirm root intrusion is a sewer camera inspection by a licensed plumber.

Mechanical clearing — A plumber can use a drain snake or hydro-jetting to clear roots from the pipe. This is a temporary fix — roots grow back, typically within 6–18 months.

Chemical treatment — Copper sulfate or foaming root killers can slow regrowth after mechanical clearing. These are not permanent solutions but can extend the interval between clearings.

Pipe lining — A plumber can install a cured-in-place liner inside the existing pipe, sealing cracks and joints that roots were using for entry. This is a longer-term solution that does not require excavation.

Pipe replacement — If the pipe is severely damaged or collapsed, replacement is the only option. Modern PVC pipe is much more resistant to root intrusion than older clay or cast iron.

Tree removal — If the tree causing the problem is close to the house and the pipe damage is severe, removing the tree may be the most cost-effective long-term solution. This is especially true for high-risk species like willows or silver maples.

The best prevention is choosing the right trees for the right locations. Keep high-risk species at least 20–30 feet from sewer lines, water mains, and foundations. For smaller yards where that distance is not possible, choose trees with less aggressive root systems.

If you are not sure whether your trees are a risk to your utilities, Tree Crew can assess root spread and proximity to known utility locations. Call (972) 999-3627 or contact us online for a free evaluation.