Main backup or local clog?
One slow sink may be local. Wastewater rising in a shower when a toilet flushes is different. Multiple fixtures backing up, gurgling toilets, floor drain overflow, or sewage odor can point to a larger drain, side sewer, septic, grinder, or STEP issue.
What to do immediately
Stop adding water
Pause laundry, dishwasher, showers, flushing, and sink use. Do not add more water to the line.
Protect people first
Keep children, pets, and shoes away from contaminated water. Do not step into sewage to test a drain.
Note the fixtures
Name the first fixture affected and any others that gurgle, rise, drain slowly, or smell.
Mention system clues
If the home has septic, side sewer, grinder, or STEP equipment, include that in the request.
Local wastewater context
Olympia has gravity pipes, pressure pipes, pump stations, and STEP systems. Nearby properties may also have septic. Do not assume the city, a side sewer, or one fixture is the cause until the backup is checked.
Avoid these risky moves
Do not keep flushing to test it. Do not mix drain chemicals. Do not remove a cleanout cap if wastewater may be under pressure. Keep people and pets away from contaminated water.