Quick Answer:
If you notice cloudy or milky water coming from a single faucet and small white particles collecting at the aerator, it’s often trapped air, mineral grit, or debris from the aerator itself. Do the clear-glass test (fill a clear glass and let it sit for a minute to see if cloudiness rises and clears), compare hot and cold taps, and remove the aerator to check for white particles. If the problem doesn’t clear, affects multiple fixtures, or leaves residue, a plumber can test the source safely.
Why This Happens
There are a few common causes:
- Air in the line: tiny bubbles make water look cloudy right after running a tap; they usually rise and clear in a glass.
- Mineral deposits or grit: calcium or other minerals can flake off and collect at the aerator or inside fixtures.
- Debris from recent work: plumbing repairs, a new pressure regulator, or changes to the supply can dislodge sediment. If you recently had work done, see Cloudy water after installing PRV for a similar scenario.
- Sediment or corrosion inside pipes or fixtures can release small white particles that then clog aerators.
Step-by-Step What to Do
1. Do the clear-glass test
Fill a clear glass from the tap and set it on the counter. Watch for a minute:
- If the cloudiness rises and the water clears from the bottom up, it’s likely tiny air bubbles and not harmful.
- If particles settle or the water stays cloudy, that suggests solid material in the water.
2. Compare hot and cold taps
Turn on the same fixture’s hot and cold separately and compare:
- If only hot water looks milky, the water heater or its sediment could be the source.
- If only cold water shows the issue, it’s likely in the supply line, faucet, or aerator — see Milky-looking water from cold tap for related causes.
- If both are affected at multiple fixtures, the problem is likely upstream of the fixture (main supply, softener, etc.).
3. Check and clean the aerator
Most aerators unscrew by hand or with a cloth for grip:
- Turn water off, unscrew the aerator, and inspect for white specks or debris.
- Rinse the parts in clean water, use a soft brush to remove deposits, then reinstall and test.
- Keep small parts together so you don’t lose them; replace the aerator if damaged.
4. Collect a sample and observe
If debris remains, collect a sample in a clear container and note whether particles settle or stain. This helps a professional diagnose the source.
5. Try a short flush (carefully)
Run cold water for a minute after cleaning the aerator to flush loose material. Avoid repeatedly flushing the water heater; if you suspect the heater, call a plumber for a safe inspection.
What Not to Do
- Don’t assume all cloudiness is harmless air — not every cloudy tap is just bubbles.
- Don’t start flushing the water heater repeatedly on your own; improper handling can cause scald risk or damage.
- Don’t use harsh chemicals or DIY corrosion treatments in plumbing unless instructed by a professional.
- If cloudiness persists, leaves residue, or affects multiple fixtures, have a plumber inspect the system rather than guessing at the cause.
When to Call a Professional
Call a plumber if any of the following apply:
- Cloudiness or particles affect more than one fixture.
- Particles leave residue, stain, or do not settle in a glass test.
- There is a change in taste, odor, or color along with the particles.
- You suspect the water heater, corrosion, or a supply-line issue. A professional can test the source safely and recommend fixes.
Safety Notes
- If you’re unsure whether the water is safe to drink, avoid using it for consumption until the cause is identified.
- Be cautious when removing aerators and working around plumbing: turn off water if needed and avoid sharp tools that can damage fixtures.
- When testing hot water, avoid scalding — run short bursts and check temperature carefully.
Common Homeowner Questions
- Why did the aerator suddenly clog? Small particles or mineral flakes can dislodge and collect at the aerator; debris from recent work can also be the cause.
- Is cloudy water dangerous? Often it’s just air or minerals, but persistent cloudiness with particles or residue should be checked by a plumber.
- Can I fix this myself? Cleaning or replacing the aerator and doing the glass test are safe DIY steps; call a professional if the issue continues or affects multiple fixtures.