Cloudy Water
Most cloudy water is harmless trapped air — here's how to tell the difference from sediment or a supply issue.
Short answer: Fill a clear glass and watch it for a minute or two. If the cloudiness clears from the bottom up, it's almost always harmless trapped air. If it doesn't clear, or you notice grit, check for a recent main break or utility notice (public water) or a well/pump issue (private well).
Common causes
- Trapped air: the most common cause, especially in winter or after utility work — clears from the bottom of the glass up within a minute or two.
- Sediment: often follows hydrant flushing or main repair work nearby (public water) or a well/pump issue (private well); see Sediment.
- A recent main break or repair: can temporarily stir up sediment in the distribution system.
Step-by-step
- Fill a clear glass with tap water and watch it for one to two minutes.
- If it clears from the bottom up, it's trapped air — no action needed.
- If it doesn't clear or you see grit, check your utility's website for recent main work or notices, or consider a well inspection if you're on a private well.
- If cloudiness or sediment persists without an explanation, contact your utility or a well professional directly.
Common mistakes
- Assuming all cloudiness signals a safety problem
- Not checking for a recent, explainable cause before contacting the utility or a professional
Official sources
- Your utility's public notices
- U.S. EPA distribution system guidance
Related
Should I boil cloudy water?
Not unless your utility has issued a boil-water advisory. Cloudiness from trapped air needs no action. If you're unsure, check current utility notices — see Boil Water Advisories.
Educational information only, not medical or regulatory advice.
Last reviewed: 2026-07-11. Report a correction.