Tree roots in your sewer line: a Portland homeowner guide

Roots get in through cracks and open joints. Portland's broken sewer and drain lines guide says sewer lines built before the mid-1960s are usually concrete or tile, and that breaks commonly occur at the curb connection and at the transition from cast iron at the house to clay or cement pipe about five feet from the dwelling. Clean Water Services lists open or offset joints and root intrusion side by side among the structural defects it sees in laterals. Lines built after 1975 are usually no-hub cast iron or plastic.

• Several drains, especially the lowest ones, slowing down at the same time
• Gurgling toilets, or water backing up into a basement floor drain or tub when the washer drains
• A clog that comes back weeks or months after a drain cleaning
• Sewage odor in the yard, or rat holes that keep reappearing, which Portland's guide lists as common signs of a broken line

A single slow sink is usually a local clog. Problems at every fixture point to the main line.

1. Camera inspection. HomeGuide's 2026 national guide puts a sewer camera inspection at $125 to $500, averaging $280, and $175 to $750 if the plumber must pull a toilet because there is no cleanout. Ask for the video with a footage counter.
2. Clearing. HomeGuide's sewer line guide lists snaking at $150 to $500 and hydro jetting at $250 to $800. Clearing restores flow, but roots usually grow back if the joint stays open.
3. Repair. The same guide lists cured-in-place lining at $90 to $250 per foot, pipe bursting at $60 to $200 per foot and full replacement at $50 to $250 per linear foot. Lining seals joints against roots; replacement is needed when the pipe is crushed or badly sagging.

Have the camera run after clearing, not only before. A pipe full of roots can hide a crack or offset joint that changes the repair and, in some cities, who pays.

The Clean Water Services lateral repairs fact sheet lists root intrusion among the structural defects it repairs in the right of way, but says a sag or belly is not a structural defect. Oregon City's lateral policy takes a narrower view: root blockages in the public lateral are not considered structural failures unless combined with one, and the owner must supply a camera video with measured footage to request a review. If the city confirms a structural failure in its portion, it reimburses the owner's verification cost.

In Portland, once the city notifies you of a sewer break on your property, you have 30 days to repair it or request more time. Repairs between the house and the property line need a plumbing permit, and work between the property line and the curb also needs a right-of-way permit.

Portland's tree permit guidance says a street tree is any tree in the city right of way, that care and maintenance of street trees is the responsibility of the adjacent property owner, and that a permit is required for any activity that may harm a street tree, as well as for pruning or removing one. Private trees 12 inches in diameter or larger, measured 4.5 feet up, need a removal permit. Before a contractor cuts roots near a street tree during a sewer dig, check whether a permit is needed.

For quotes and hiring, see our sewer line repair guide and hiring guide. To reach a plumber, call one of the licensed contractors listed on this page or see all listed contractors. Questions about this guide: email us. We do not take service requests.