A main sewer line clog usually shows up as slow drains throughout the house, gurgling, or a backup in the lowest drain. Roots, grease and a damaged pipe are the usual causes. Stop running water and call the number to describe the symptoms and get a quote from a local contractor.
Signs the main line is the problem
Several fixtures drain slowly at the same time.
Water or sewage comes up in the lowest drain, such as a basement floor drain or tub.
A toilet flush makes another fixture gurgle.
A sewer odor inside or near the house.
Wet or unusually green patches in the yard over the line.
Any of these is worth a call. Sewage backups should be treated as urgent, and the area should be kept clear of children and pets.
Common causes
Grease buildup, roots working into joints, a bellied or collapsed section, and objects flushed or washed down the drain are the usual causes. The cause decides the fix. A clog can be cleared with a cable or jetter. A collapsed or root-damaged section may need a repair or replacement.
What to say on the call
Which fixtures are affected, and where water is coming up.
When it started and whether it has happened before.
The age of the home and any known issues with the sewer line.
Ask whether a camera inspection is part of the quote, and what happens if it shows damage.
While waiting for the contractor
Stop running water in the house, especially the washing machine, dishwasher and showers, because everything drains to the same line. Keep people and pets away from any sewage on the floor, and do not pour chemicals into a backed-up line, since a contractor may need to work on it next. If sewage is spreading or anything feels unsafe, treat it as urgent.
How to tell it is the main line
More than one fixture is slow at the same time.
A toilet gurgles when the washing machine drains.
Water comes up in the lowest drain in the house, usually a floor drain or basement tub, when upstairs fixtures run.
A sewage smell around the foundation or in the yard near the cleanout.
Common causes
Tree roots finding their way into the pipe joints are a frequent cause in older yards. Grease buildup, objects flushed down the toilet and sagging or cracked sections of pipe also cause blockages. The cause matters because clearing the line and fixing the line are different jobs.
The cleanout
Most homes have a capped cleanout pipe, often outside near the foundation or in a basement or crawl space. A contractor accesses the main line through it. Knowing where it is, or describing where the line leaves the house, saves time on the call.
What to do while waiting
Stop running water in the house, especially the washing machine and dishwasher, since every gallon has nowhere to go. Keep people and pets out of any area with standing sewage, and do not use chemical cleaners on a main line backup.