Quick Answer:
Most often this is air or loosened sediment in the water and sewer lines after pressure changes during a city outage. Start by purging air from your plumbing: run the cold and hot faucets briefly at several fixtures, then retest the toilet while other fixtures are used. If the gurgling continues or you see backups or strong sewer smells, call a plumber.
Why This Happens
When the municipal supply is shut off and then restored, pressure changes can draw air into pipes or shift small debris that sits in the lines. That air or sediment can make noises as water moves past traps and through the venting system. In most homes the problem clears once trapped air is pushed out and normal flow resumes. For related situations, you may also want to see Gurgling after winterization and Toilet gurgles when washer drains for other common causes.
Step-by-Step What to Do
Step 1 — Wait a short time
- Give your plumbing a few minutes after service returns. A brief settling period often lets pressure normalize and small air pockets clear on their own.
Step 2 — Purge air by running faucets
- At the highest and lowest points in the house, open cold and hot faucets one at a time for 10–30 seconds to let trapped air escape.
- Flush uninterested fixtures (sinks, tubs) only as needed while doing this; do not repeatedly flush the toilet itself to try to clear air.
- Collect water in a bucket if you’re concerned about splashing or if water quality looks dirty at first.
Step 3 — Retest while using other fixtures
- With faucets running elsewhere, flush the toilet and listen. If the gurgle appears only when another fixture drains, the issue may be a partial vent or shared drain flow.
- Try washing machine or shower cycles to see if the toilet gurgles during those uses.
Step 4 — Check traps and visible drains
- Look for slow drains, standing water, or odors at nearby fixtures. A dry trap (rare after an outage) or debris in a drain can cause noises.
- Do not crawl into tight spaces or attempt roof vent work yourself; that belongs to a safe, experienced person.
Step 5 — If it persists, document and call a plumber
- Note when the gurgling happens and which fixtures trigger it. If it continues after purging and testing, contact a licensed plumber to inspect vents, the sewer line, or municipal connections.
What Not to Do
- Don’t keep flushing after outages to clear gurgling—purge air properly; if it continues, a plumber is appropriate.
- Don’t pour caustic drain chemicals into toilets hoping to clear noise; they won’t fix air or vent problems and can damage pipes.
- Don’t stick objects into traps or drains to try to dislodge material yourself; this can push blockages deeper or harm the fixture.
- Avoid climbing on the roof to check or clear the vent stack unless you are trained and equipped for safe roof work.
When to Call a Professional
- Persistent gurgling after you’ve purged air and tested multiple fixtures.
- Multiple fixtures are slow or showing sewage backup.
- Strong sewer odors indoors or raw sewage in drains or outside cleanouts.
- If you suspect a blocked or damaged vent stack, broken sewer line, or a problem that could affect neighbors or the street connection.
Safety Notes
- Avoid chemical cleaners if you might need a plumber; they can be hazardous to workers and damage equipment.
- Do not attempt roof vent work without fall protection and experience—falls are a common serious injury on projects like this.
- If you see sewage backing up, stop using water and call a professional promptly to limit contamination and damage.
Common Homeowner Questions
- Why did this start after the outage? Air and pressure changes or shifted sediment during the outage are the usual causes.
- Is it safe to run my faucets to clear it? Yes—carefully running faucets to purge air is the correct first step.
- When should I get a plumber? If gurgling keeps happening after purging, if you have backups, or if there are strong sewer smells, call a plumber.