More than one clogged drain at the same time almost always means a problem deeper in the system — the main sewer line, a shared branch line, or a venting issue. Individual fixture clogs are usually isolated to that fixture. Multiple slow or backed-up drains call for a main-line camera inspection.
Common causes
- Main sewer line blockage
- Tree roots in the main line
- Shared branch line clog
- Improper venting causing slow drainage
- Sewer main backup from city side
Confirm with a sewer camera inspection, then clear with drain cleaning or hydro jetting.
