Originally Posted at Family Handyman
If you live on a wooded lot and have problems with tree roots invading your sewer system and clogging it up, don't assume you have to cut the trees down! As you can see from the photo, the tree roots work their way in through cracks or joints in older sewer lines made of clay tile, cast iron or an asphalt composite style called "orangeberg" piping. The roots are seeking that nutrient rich soup you're sending down the drains and toilets (there's no accounting for taste). Clay and cast iron are rarely used anymore because of those loose-fitting joints that tree roots can penetrate. These materials are also heavy, hard to work with, expensive, brittle and prone to breakage. Nowadays nearly all sewer lines are made of plastic pipe - it's cheap, tough and light weight, and the joints are impervious to tree roots.
You have three options, none ideal: Continue reaming the lines periodically, cut down the trees, or call in the pros.
Larger sewer-cleaning companies will ream out the line or send a mini video camera inside the pipe to determine the exact problem. They'll find out if the line is crushed, cracked or sloped improperly, or if tree roots are worming their way through cracks or loose jionts. Then they'll recommend a course of action, which could be:
- Digging up the old line and replacing it with plastic.
- Treating the line with a poison formulated to kill nearby tree roots. That way it'll rake much longer for new roots to cause problems. These poisons are designed to kill just problem roots - not the whole tree.
- Sealing the line by lining the existing pipe wit an internal plastic fabric and cement. Companies have been doing this for years on larger lines and are just beginning to line residential ones. Chances of finding a local company that does residential sewer lining are slim, but it doesn't hurt to ask.
- Purchase or rent your own power auger and clean out the lines yourself. Power augers can run around $400 or more.